0001558370-23-013598 | 10-Q | XBRL Viewer

Accounts Payable and Accrued Expenses (Tables)

6 Months Ended

Jun. 30, 2023

Accounts Payable and Accrued Expenses

Schedule of Accounts Payable and Accrued Expenses

Accounts payable and accrued expenses consist of the following:


	June 30, 2023		December 31, 2022
Accounts payable	$	12,122	$	9,604
Accrued research projects		6,416		5,200
Accrued compensation and benefits		4,196		5,219
Accrued professional fees and other		1,741		1,517
Total	$	24,475	$	21,540

Inventory, net

6 Months Ended

Jun. 30, 2023

Inventory, net

Inventory, net

7. Inventory, net

Inventory, net consists of the following:


	June 30, 2023		December 31, 2022
Raw materials	$	2,571	$	1,918
Work-in-process		863		499
		3,434		2,417
Less Inventory Reserve for Obsolescence		(14)		(34)
Total	$	3,420	$	2,383

As of June 30, 2023 and December 31, 2022, inventory balances include inventory costs subsequent to regulatory approval of KORSUVA injection on August 23, 2021.

CONDENSED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
CONDENSED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	Jun. 30, 2023	Jun. 30, 2022
Operating activities
Net loss	$ (58,144)	$ (31,955)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation expense	6,795	10,359
Depreciation and amortization	118	126
Amortization expense component of lease expense	759	695
(Accretion)/amortization of available-for-sale marketable securities, net	(56)	530
Changes in operating assets and liabilities:
Accounts receivable, net - related party	(6,864)	(8,003)
Inventory, net	(1,037)	(876)
Other receivables	76	(13)
Prepaid expenses	1,291	(3,507)
Accounts payable and accrued expenses	2,935	3,471
Operating lease liabilities	(936)	(855)
Net cash used in operating activities	(55,063)	(30,028)
Investing activities
Proceeds from maturities of available-for-sale marketable securities	72,265	94,250
Proceeds from redemptions of available-for-sale marketable securities, at par	4,000
Purchases of available-for-sale marketable securities	(25,754)	(31,099)
Purchases of property and equipment		(43)
Net cash provided by investing activities	50,511	63,108
Financing activities
Proceeds from the exercise of stock options	560	185
Net cash provided by financing activities	560	185
Net (decrease) increase in cash, cash equivalents and restricted cash	(3,992)	33,265
Cash, cash equivalents and restricted cash at beginning of period	64,149	13,861
Cash, cash equivalents and restricted cash at end of period	$ 60,157	$ 47,126

Net Loss Per Share - Additional Information (Detail) - shares	Jun. 30, 2023	Dec. 31, 2022	Jun. 30, 2022
Net Loss Per Share
Number of options outstanding	8,134,597	7,689,449	7,419,027
Number of restricted stock units outstanding	791,853		648,450

Fair Value Measurements - Summary of Financial Assets Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Financial assets
Available-for-sale marketable securities	$ 43,495	$ 93,008
Restricted cash	408	408
Restricted cash, non-current	1,500
Recurring [Member]
Financial assets
Total financial assets	103,652	157,157
U.S. Government Agency Obligations [Member]
Financial assets
Available-for-sale marketable securities	9,003	8,877
U.S. Government Agency Obligations [Member] \| Recurring [Member]
Financial assets
Available-for-sale marketable securities	9,003	8,877
Corporate Bonds [Member]
Financial assets
Available-for-sale marketable securities	19,675	35,185
Corporate Bonds [Member] \| Recurring [Member]
Financial assets
Available-for-sale marketable securities	19,675	35,185
Commercial Paper [Member]
Financial assets
Available-for-sale marketable securities		26,875
Municipal Bonds [Member]
Financial assets
Available-for-sale marketable securities	14,817	22,071
Municipal Bonds [Member] \| Recurring [Member]
Financial assets
Available-for-sale marketable securities	14,817	22,071
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] \| Recurring [Member]
Financial assets
Total financial assets	60,157	64,149
Significant Other Observable Inputs (Level 2) [Member] \| Recurring [Member]
Financial assets
Total financial assets	43,495	93,008
Significant Other Observable Inputs (Level 2) [Member] \| U.S. Government Agency Obligations [Member] \| Recurring [Member]
Financial assets
Available-for-sale marketable securities	9,003	8,877
Significant Other Observable Inputs (Level 2) [Member] \| Corporate Bonds [Member] \| Recurring [Member]
Financial assets
Available-for-sale marketable securities	19,675	35,185
Significant Other Observable Inputs (Level 2) [Member] \| Municipal Bonds [Member] \| Recurring [Member]
Financial assets
Available-for-sale marketable securities	14,817	22,071
Money Market Funds [Member] \| Recurring [Member]
Financial assets
Cash and cash equivalents	58,249	63,741
Restricted cash	1,908	408
Money Market Funds [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] \| Recurring [Member]
Financial assets
Cash and cash equivalents	58,249	63,741
Restricted cash	$ 1,908	408
Commercial Paper [Member] \| Recurring [Member]
Financial assets
Available-for-sale marketable securities		26,875
Commercial Paper [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| Recurring [Member]
Financial assets
Available-for-sale marketable securities		$ 26,875

Related Party Transactions (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022
Related Party Transaction [Line Items]
Accounts due from related parties	$ 10,124		$ 10,124		$ 3,260
Revenue from contract with customer	6,933	$ 23,003	13,098	$ 27,793
Commercial supply revenue
Related Party Transaction [Line Items]
Revenue from contract with customer	1,400		4,591	4,790
Collaborative revenue
Related Party Transaction [Line Items]
Revenue from contract with customer	5,410	8,003	8,160	8,003
Royalty revenue
Related Party Transaction [Line Items]
Revenue from contract with customer	123		248
License and milestone fees
Related Party Transaction [Line Items]
Revenue from contract with customer		15,000		15,000
CSL Vifor Profit Sharing [Member] \| Collaborative revenue
Related Party Transaction [Line Items]
Revenue from contract with customer	$ 5,410	8,003	$ 8,160	8,003
Vifor Agreement No 2 [Member] \| License and milestone fees
Related Party Transaction [Line Items]
Revenue from related parties		15,000		15,000
Vifor International Ltd. [Member]
Related Party Transaction [Line Items]
Shares owned as a result of upfront and milestone payments	7,396,770		7,396,770
Related party ownership percentage	13.70%		13.70%
CSL Vifor [Member]
Related Party Transaction [Line Items]
Accounts due from related parties	$ 10,124		$ 10,124		$ 3,260
CSL Vifor [Member] \| Commercial supply revenue
Related Party Transaction [Line Items]
Revenue from related parties	1,400		4,591	4,790
Related party cost of goods sold	1,418		4,008	2,081
CSL Vifor [Member] \| CSL Vifor Profit Sharing [Member] \| Collaborative revenue
Related Party Transaction [Line Items]
Revenue from contract with customer	5,410	$ 8,003	8,160	$ 8,003
CSL Vifor [Member] \| CSL Vifor Kapruvia [Member] \| Royalty revenue
Related Party Transaction [Line Items]
Revenue from contract with customer	$ 123		$ 248

Stock-Based Compensation - Summary of Compensation Expense Relating to Stock Options (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Excess tax benefits from stock option activity or stock-based compensation expense recognized in cash flows from operations			$ 0	$ 0
Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Compensation expense	$ 2,881	$ 3,702	5,602	7,649
Options [Member] \| Research and Development [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Compensation expense	1,447	1,744	2,927	3,661
Options [Member] \| General and Administrative [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Compensation expense	1,434	1,958	2,675	3,988
Restricted Stock Units [Member] \| Director [Member] \| General and Administrative [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Compensation expense	135	238	258	377
Restricted Stock Units [Member] \| Employees [Member] \| Research and Development [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Compensation expense	116	198	295	365
Restricted Stock Units [Member] \| Employees [Member] \| General and Administrative [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Compensation expense	$ 310	$ 517	$ 639	$ 1,969

Revenue Recognition (Tables)

6 Months Ended

Jun. 30, 2023

Revenue Recognition

Schedule of disaggregation of revenue


	Three Months Ended June 30,				Six Months Ended June 30,
	2023		2022		2023		2022
Collaborative revenue
CSL Vifor (KORSUVA injection profit sharing)	$	5,410	$	8,003	$	8,160	$	8,003
Total collaborative revenue	$	5,410	$	8,003	$	8,160	$	8,003
Commercial supply revenue
CSL Vifor* (KORSUVA injection)	$	1,400	$	—	$	4,591	$	4,790
Total commercial supply revenue	$	1,400	$	—	$	4,591	$	4,790
Royalty revenue
CSL Vifor (Kapruvia ex U.S.)	$	123	$	—	$	248	$	—
Total royalty revenue	$	123	$	—	$	248	$	—
License and milestone fees
Vifor Fresenius Medical Care Renal Pharma Ltd.	$	—	$	15,000	$	—	$	15,000
Total milestone and fees	$	—	$	15,000	$	—	$	15,000
Clinical compound revenue
Maruishi	$	—	$	—	$	99	$	—
Total clinical compound revenue	$	—	$	—	$	99	$	—

_____________________________

* Includes amounts earned from Vifor International prior to Vifor International’s assignment of its rights and obligations to Vifor Fresenius Medical Care Renal Pharma Ltd. in May 2022.

Available-for-Sale Marketable Securities - Summary of Available-for-Sale Marketable Securities by Major Type of Security (Detail) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	$ 44,225	$ 94,680
Gross Unrealized Gains		2
Gross Unrealized Losses	(730)	(1,674)
Estimated fair value	43,495	93,008
U.S. Government Agency Obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	9,500	9,500
Gross Unrealized Losses	(497)	(623)
Estimated fair value	9,003	8,877
Corporate Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	19,859	35,828
Gross Unrealized Losses	(184)	(643)
Estimated fair value	19,675	35,185
Commercial Paper [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized cost		26,879
Gross Unrealized Gains		2
Gross Unrealized Losses		(6)
Estimated fair value		26,875
Municipal Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	14,866	22,473
Gross Unrealized Losses	(49)	(402)
Estimated fair value	$ 14,817	$ 22,071

Accounts Payable and Accrued Expenses

6 Months Ended

Jun. 30, 2023

Accounts Payable and Accrued Expenses

Accounts Payable and Accrued Expenses

9. Accounts Payable and Accrued Expenses

Accounts payable and accrued expenses consist of the following:


	June 30, 2023		December 31, 2022
Accounts payable	$	12,122	$	9,604
Accrued research projects		6,416		5,200
Accrued compensation and benefits		4,196		5,219
Accrued professional fees and other		1,741		1,517
Total	$	24,475	$	21,540

Stock-Based Compensation - Restricted Stock Unit Activity (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended		6 Months Ended
	Jun. 01, 2023	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Number of Units
Outstanding, Ending Balance		791,853	648,450	791,853	648,450
Employees [Member] \| Restricted Stock Units [Member] \| General and Administrative [Member]
Number of Units
Compensation expense		$ 310	$ 517	$ 639	$ 1,969
2014 Equity Incentive Plan [Member] \| Non-employee Directors [Member] \| June 2023 \| Restricted Stock Units [Member]
Number of Units
Awarded	194,172
Outstanding, Ending Balance		194,172		194,172
Weighted Average Grant Date Fair Value
Weighted-average grant date fair value, awarded	$ 3.09
2014 Equity Incentive Plan [Member] \| Non-employee Directors [Member] \| June 2023 \| Restricted Stock Units [Member] \| General and Administrative [Member]
Number of Units
Compensation expense		$ 49		$ 49
2014 Equity Incentive Plan [Member] \| Employees And Non-Employee Members Of Board Of Directors [Member] \| Restricted Stock Units [Member]
Number of Units
Outstanding, Beginning Balance				372,513
Awarded				601,172
Vested and released				(178,247)
Forfeited				(3,585)
Outstanding, Ending Balance		791,853		791,853
Weighted Average Grant Date Fair Value
Weighted-average grant date fair value, outstanding, Beginning Balance				$ 13.20
Weighted-average grant date fair value, awarded				7.81
Weighted-average grant date fair value, vested and released				12.15
Weighted-average grant date fair value, forfeited				10.46
Weighted-average grant date fair value, outstanding, Ending Balance		$ 9.36		$ 9.36
2014 Equity Incentive Plan [Member] \| Employees [Member] \| Time-based Restricted Stock Units [Member] \| General and Administrative [Member]
Number of Units
Compensation expense			$ 131

Income Taxes

6 Months Ended

Jun. 30, 2023

Income Taxes

Income Taxes

15. Income Taxes

The Company has recognized a full tax valuation allowance against its deferred tax assets as of June 30, 2023 and December 31, 2022. The tax benefit related to the exercise of stock options is recognized as a deferred tax asset that is offset by a corresponding valuation allowance. As such, the Company’s effective tax rate is zero for each of the three and six months ended June 30, 2023 and 2022.

Historically, the Company’s benefit from income taxes related to state R&D tax credits exchanged for cash pursuant to the Connecticut R&D Tax Credit Exchange Program, which permits qualified small businesses engaged in R&D activities within Connecticut to exchange their unused R&D tax credits for a cash amount equal to 65% of the value of the exchanged credits. It was not eligible to exchange its R&D tax credit for cash during the three and six months ended June 30, 2023 and 2022, therefore there was no benefit from income taxes for the three and six months ended June 30, 2023 and 2022. As of June 30, 2023, the Company recorded $697 within income tax receivable which related to the 2020 R&D credit.

The Inflation Reduction Act of 2022 included tax legislation that became effective early in 2023. Significant legislation for corporate taxpayers includes a corporate alternative minimum tax of 15.0% for companies with $1,000,000 or more in average net financial statement profits over the three previous years, as well as a 1.0% indirect excise tax on the repurchase of shares by a publicly traded company. The Company does not expect this legislation to have an effect on its tax provision as of June 30, 2023; however, the Company will continue to evaluate the effect on the tax provision each reporting period.

- Definition

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 21
-URI https://asc.fasb.org/extlink&oid=121826272&loc=d3e32857-109319

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 11.C)
-URI https://asc.fasb.org/extlink&oid=122134291&loc=d3e330215-122817

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 17
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=121826272&loc=d3e32809-109319

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 6.I.5.Q1)
-URI https://asc.fasb.org/extlink&oid=122134291&loc=d3e330036-122817

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 14
-URI https://asc.fasb.org/extlink&oid=121826272&loc=d3e32705-109319

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 270
-Section 50
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=6424409&loc=d3e44925-109338

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-URI https://asc.fasb.org/topic&trid=2144680

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=6424122&loc=d3e41874-109331

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(h)(2))
-URI https://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

+ Details

Accumulated Other Comprehensive Loss

6 Months Ended

Jun. 30, 2023

Accumulated Other Comprehensive Loss

Accumulated Other Comprehensive Loss

4. Accumulated Other Comprehensive Loss

The following table summarizes the changes in accumulated other comprehensive loss, net of tax, from unrealized gains (losses) on available-for-sale marketable securities, the Company’s only component of accumulated other comprehensive loss, for the six months ended June 30, 2023 and 2022, respectively.


	Total Accumulated
	Other Comprehensive
	Loss
Balance, December 31, 2022	$	(1,672)
Other comprehensive income before reclassifications		942
Amount reclassified from accumulated other comprehensive loss		—
Net current period other comprehensive income		942
Balance, June 30, 2023	$	(730)

Balance, December 31, 2021	$	(358)
Other comprehensive loss before reclassifications		(1,689)
Amount reclassified from accumulated other comprehensive loss		—
Net current period other comprehensive loss		(1,689)
Balance, June 30, 2022	$	(2,047)

Amounts reclassified out of accumulated other comprehensive loss into net loss are determined by specific identification. There were no reclassifications out of accumulated other comprehensive loss and into net loss for each of the three and six months ended June 30, 2023 and 2022.

Stockholders' Equity - Additional Information (Detail) - USD ($) $ in Thousands	1 Months Ended							3 Months Ended				6 Months Ended
	Jun. 30, 2023	Apr. 30, 2023	Feb. 28, 2023	Jan. 31, 2023	Jun. 30, 2022	Mar. 31, 2022	Feb. 28, 2022	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2023	Dec. 31, 2022
Sale Of Stock [Line Items]
Common stock, shares issued	54,068,806							54,068,806				54,068,806	53,797,341
Unsold Securities Under Shelf Registration Statement dated April 4, 2019 [Member]
Sale Of Stock [Line Items]
Aggregate offering price of securities						$ 154,525					$ 154,525
Open Market Sales Agreement [Member] \| Jeffries LLC [Member]
Sale Of Stock [Line Items]
Common stock, shares issued												0
Stock Sale Commission Percentage						3.00%
Open Market Sales Agreement [Member] \| Maximum [Member] \| Jeffries LLC [Member]
Sale Of Stock [Line Items]
Aggregate offering price of securities						$ 80,000					80,000
2022 Shelf Registration Statement [Member] \| Maximum [Member]
Sale Of Stock [Line Items]
Aggregate offering price of securities						$ 300,000					$ 300,000
Common Stock
Sale Of Stock [Line Items]
Restricted stock units vested shares								94,454	83,793	89,075	109,943
Restricted Stock Units [Member] \| Common Stock \| Board of Directors Chairman [Member] \| June 2022
Sale Of Stock [Line Items]
Restricted stock units vested shares					11,876
Performance Restricted Stock Units [Member] \| Common Stock \| Executive Officers [Member] \| March 2022
Sale Of Stock [Line Items]
Restricted stock units vested shares						37,999
Time-based Restricted Stock Units [Member] \| Common Stock \| Director [Member] \| June 2022
Sale Of Stock [Line Items]
Vesting period of awards granted	1 year				1 year
Restricted stock units vested shares	59,380				43,200
Time-based Restricted Stock Units [Member] \| Common Stock \| Executive Officers [Member] \| December 2021
Sale Of Stock [Line Items]
Restricted stock units vested shares	26,199
Time-based Restricted Stock Units [Member] \| Common Stock \| Executive Officers [Member] \| February 2022
Sale Of Stock [Line Items]
Vesting period of awards granted			3 years				3 years
Restricted stock units vested shares			42,920				32,666
Time-based Restricted Stock Units [Member] \| Common Stock \| Executive Officers [Member] \| October 2021
Sale Of Stock [Line Items]
Restricted stock units vested shares		8,875		8,875
Time-based Restricted Stock Units [Member] \| Common Stock \| Executive Officers [Member] \| March 2021
Sale Of Stock [Line Items]
Vesting period of awards granted									3 years
Restricted stock units vested shares									15,999
Time-based Restricted Stock Units [Member] \| Common Stock \| Executive Officers [Member] \| February 2020
Sale Of Stock [Line Items]
Vesting period of awards granted			3 years
Restricted stock units vested shares			15,999
Time-based Restricted Stock Units [Member] \| Common Stock \| Former Chief Executive Officer [Member] \| June 2022
Sale Of Stock [Line Items]
Restricted stock units vested shares					33,999
Time-based Restricted Stock Units [Member] \| Common Stock \| Chief Executive Officer [Member] \| March 2022
Sale Of Stock [Line Items]
Vesting period of awards granted						3 years
Restricted stock units vested shares						39,278

Commitments and Contingencies - Additional Information (Detail) $ in Thousands		1 Months Ended		3 Months Ended		6 Months Ended
	May 11, 2023 USD ($)	Jul. 31, 2021	Jul. 31, 2019 agreement	Jun. 30, 2023 USD ($)	Jun. 30, 2022 USD ($)	Jun. 30, 2023 USD ($)	Jun. 30, 2022 USD ($)
Other Commitments [Line Items]
Operating lease liabilities				$ 982		$ 982
New Corporate Headquarters Office Space [Member]
Other Commitments [Line Items]
Operating lease, renewable term	5 years
Lease, annual fixed rent	$ 1,300
Lease, fixed rent, annual increase, percent	2.50%
Option to extend	true
Operating Lease, renewable term	5 years
Stamford Operating Lease [Member]
Other Commitments [Line Items]
Operating lease cost				406	$ 406	813	$ 812
Stamford Operating Lease [Member] \| Research and Development [Member]
Other Commitments [Line Items]
Operating lease cost				284	284	569	568
Stamford Operating Lease [Member] \| General and Administrative [Member]
Other Commitments [Line Items]
Operating lease cost				122	122	244	244
Non-Exclusive License Agreement \| Enteris Biopharma, Inc. [Member]
Other Commitments [Line Items]
Payment of milestone payment				$ 0	$ 0	$ 0	$ 0
Patheon MSA [Member] \| Patheon and Patheon Manufacturing Services LLC [Member]
Other Commitments [Line Items]
Number of related product agreements \| agreement			2
API Commercial Supply Agreement - PPL [Member]
Other Commitments [Line Items]
Agreement renewal term		5 years

Inventory, net - Schedule of Inventories (Detail) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Inventory, net
Raw materials	$ 2,571	$ 1,918
Work-in-process	863	499
Inventory gross	3,434	2,417
Less Inventory Reserve for Obsolescence	(14)	(34)
Total	$ 3,420	$ 2,383

Available-for-Sale Marketable Securities

6 Months Ended

Jun. 30, 2023

Available-for-Sale Marketable Securities

Available-for-Sale Marketable Securities

3. Available-for-Sale Marketable Securities

As of June 30, 2023 and December 31, 2022, the Company’s available-for-sale marketable securities consisted of debt securities issued by U.S. government-sponsored entities and investment grade institutions as well as municipal bonds.

The following tables summarize the Company’s available-for-sale marketable securities by major type of security as of June 30, 2023 and December 31, 2022:

As of June 30, 2023


			Gross Unrealized				Estimated Fair
Type of Security	Amortized Cost		Gains		Losses		Value
U.S. government agency obligations	$	9,500	$	—	$	(497)	$	9,003
Corporate bonds		19,859		—		(184)		19,675
Municipal bonds		14,866		—		(49)		14,817
Total available-for-sale marketable securities	$	44,225	$	—	$	(730)	$	43,495

As of December 31, 2022


			Gross Unrealized				Estimated Fair
Type of Security	Amortized Cost		Gains		Losses		Value
U.S. government agency obligations	$	9,500	$	—	$	(623)	$	8,877
Corporate bonds		35,828		—		(643)		35,185
Commercial paper		26,879		2		(6)		26,875
Municipal bonds		22,473		—		(402)		22,071
Total available-for-sale marketable securities	$	94,680	$	2	$	(1,674)	$	93,008

The following tables summarize the fair value and gross unrealized losses of the Company’s available-for-sale marketable securities by investment category and disaggregated by the length of time that individual debt securities have been in a continuous unrealized loss position as of June 30, 2023 and December 31, 2022:

As of June 30, 2023


	Less than 12 Months				12 Months or Greater				Total
			Gross				Gross				Gross
	Fair		Unrealized		Fair		Unrealized		Fair		Unrealized
	Value		Losses		Value		Losses		Value		Losses
U.S. government agency obligations	$	—	$	—	$	9,003	$	(497)	$	9,003	$	(497)
Corporate bonds		—		—		19,675		(184)		19,675		(184)
Municipal bonds		—		—		7,702		(49)		7,702		(49)
Total	$	—	$	—	$	36,380	$	(730)	$	36,380	$	(730)

As of December 31, 2022


	Less than 12 Months				12 Months or Greater				Total
			Gross				Gross				Gross
	Fair		Unrealized		Fair		Unrealized		Fair		Unrealized
	Value		Losses		Value		Losses		Value		Losses
U.S. government agency obligations	$	—	$	—	$	8,877	$	(623)	$	8,877	$	(623)
Corporate bonds		1,470		(26)		33,715		(617)		35,185		(643)
Commercial paper		15,906		(6)		—		—		15,906		(6)
Municipal bonds		982		(16)		19,589		(386)		20,571		(402)
Total	$	18,358	$	(48)	$	62,181	$	(1,626)	$	80,539	$	(1,674)

As of June 30, 2023 and December 31, 2022, no allowance for credit losses were recognized on the Company’s available-for-sale debt securities as no portion of the unrealized losses associated with those securities were due to credit losses. The information that the Company considered in reaching the conclusion that an allowance for credit losses was not necessary is as follows:

As of June 30, 2023 and December 31, 2022, the Company held a total of 17 out of 22 positions and 35 out of 39 positions, respectively, that were in an unrealized loss position, all of which had been in an unrealized loss position for 12 months or greater as of June 30, 2023. Unrealized losses individually and in aggregate, including any in an unrealized loss position for 12 months or greater, were not considered to be material for each respective period. Based on the Company’s review of these securities, the Company believes that the cost basis of its available-for-sale marketable securities is recoverable.

U.S. government agency obligations. The unrealized losses on the Company’s investments in direct obligations of government agencies were due to changes in interest rates and non-credit related factors. The credit ratings of these investments in the Company’s portfolio have not been downgraded below investment grade status. The contractual terms of these investments do not permit the issuer to repay principal at a price less than the amortized cost bases of the investments, which is equivalent to the par value on the maturity date. The Company expects to recover the entire amortized cost bases of these securities on the maturity date. The Company does not intend to sell these investments, and it is not “more likely than not” that the Company will be required to sell these investments before recovery of their amortized cost bases. The Company held 3 out of 3 positions for its U.S. government agency obligations, that were in unrealized loss positions as of June 30, 2023.

Corporate bonds and municipal bonds. The unrealized losses on the Company’s investments in corporate bonds and municipal bonds were due to changes in interest rates and non-credit related factors. The credit ratings of these investments in the Company’s portfolio have not been downgraded below investment grade status. The contractual terms of these investments do not permit the issuer to repay principal at a price less than the amortized cost bases of the investments, which is equivalent to the par value on the maturity date. The Company expects to recover the entire amortized cost bases of these securities on the maturity date. The Company does not intend to sell these investments, and it is not “more likely than not” that the Company will be required to sell these investments before recovery of their amortized cost bases. The Company held 8 out of 8 positions for its corporate bonds, and 6 out of 11 positions for its municipal bonds, that were in unrealized loss positions as of June 30, 2023.

The Company classifies its marketable debt securities based on their contractual maturity dates. As of June 30, 2023, the Company’s marketable debt securities mature at various dates through November 2024. The amortized cost and fair values of marketable debt securities by contractual maturity were as follows:


	As of June 30, 2023				As of December 31, 2022
Contractual maturity	Amortized Cost		Fair Value		Amortized Cost		Fair Value
Less than one year	$	36,725	$	36,442	$	82,678	$	81,658
One year to two years		7,500		7,053		12,002		11,350
Total	$	44,225	$	43,495	$	94,680	$	93,008

All available-for-sale marketable securities are classified as marketable securities, current or marketable securities, non-current depending on the contractual maturity date of the individual available-for-sale security. Other income, net includes interest and dividends, accretion/amortization of discounts/premiums, realized gains and losses on sales of securities and credit loss expense due to declines in the fair value of securities, if any. The cost of securities sold is based on the specific identification method.

There were no sales of available-for-sale marketable securities during each of the three and six months ended June 30, 2023 and 2022.

As of June 30, 2023 and December 31, 2022, accrued interest receivables on the Company’s available-for-sale debt securities were $420 and $489, respectively, and were included within other receivables.

Revenue Recognition - Additional Information (Detail) - USD ($) $ in Thousands	1 Months Ended			3 Months Ended		6 Months Ended
	Apr. 30, 2022	Mar. 31, 2022	Jan. 31, 2022	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022
Collaboration Arrangement [Line Items]
Accounts receivable, net - related party				$ 10,124		$ 10,124		$ 3,260
Total revenue				6,933	$ 23,003	13,098	$ 27,793
Commercial supply revenue
Collaboration Arrangement [Line Items]
Total revenue				1,400		4,591	4,790
License and milestone fees
Collaboration Arrangement [Line Items]
Total revenue					15,000		15,000
Royalty revenue
Collaboration Arrangement [Line Items]
Total revenue				123		248
Collaborative revenue
Collaboration Arrangement [Line Items]
Total revenue				5,410	8,003	8,160	8,003
Clinical compound revenue
Collaboration Arrangement [Line Items]
Total revenue						99
CSL Vifor Profit Sharing [Member] \| Collaborative revenue
Collaboration Arrangement [Line Items]
Total revenue				5,410	8,003	8,160	8,003
CSL Vifor, Maruishi and CKDP Agreements [Member]
Collaboration Arrangement [Line Items]
Other contract Assets				0		0		0
Other contract liabilities				0		0		0
Maruishi Pharmaceutical Co., Ltd. [Member] \| Clinical compound revenue
Collaboration Arrangement [Line Items]
Total revenue				0	0	99	0
CSL Vifor [Member]
Collaboration Arrangement [Line Items]
Accounts receivable, net - related party				10,124		10,124		$ 3,260
CSL Vifor [Member] \| Commercial supply revenue
Collaboration Arrangement [Line Items]
Total revenue				1,400		4,591	4,790
CSL Vifor [Member] \| Commercial Supply Revenue With No Associated Costs Of Goods Sold [Member]
Collaboration Arrangement [Line Items]
Total revenue			$ 2,295		0
Cost of goods sold			$ 0
CSL Vifor [Member] \| Commercial Supply Revenue With Associated Costs Of Goods Sold [Member]
Collaboration Arrangement [Line Items]
Revenue		$ 2,495
Cost of goods sold		$ 2,081		1,418		4,008
CSL Vifor [Member] \| Royalty revenue
Collaboration Arrangement [Line Items]
Total revenue					$ 0		$ 0
CSL Vifor [Member] \| Vifor Fresenius Medical Care Renal Pharma Ltd Agreement No 2 [Member] \| License and milestone fees \| Regulatory Milestones [Member]
Collaboration Arrangement [Line Items]
Proceeds from milestone payments	$ 15,000
CSL Vifor [Member] \| CSL Vifor Kapruvia [Member] \| Royalty revenue
Collaboration Arrangement [Line Items]
Total revenue				$ 123		$ 248

Restricted Cash (Tables)

6 Months Ended

Jun. 30, 2023

Restricted Cash

Schedule of Reconciliation of Cash, Cash Equivalents and Restricted Cash


	June 30, 2023		December 31, 2022
Cash and cash equivalents	$	58,249	$	63,741
Restricted cash, current assets		408		408
Restricted cash, long-term assets		1,500		—
Total cash, cash equivalents, and restricted cash shown in the Condensed Statements of Cash Flows	$	60,157	$	64,149

Stock-Based Compensation - Summary of Stock Option Activity (Detail)	3 Months Ended	6 Months Ended
	Jun. 30, 2022 shares	Jun. 30, 2023 $ / shares shares
Stock-Based Compensation
Number of Options, Outstanding, Beginning Balance		7,689,449
Number of Options, Granted		1,798,921
Number of Options, Exercised		(93,218)
Number of Options, Forfeited		(117,629)
Number of Options, Expired		(1,142,926)
Number of Options, Outstanding, Ending Balance	7,419,027	8,134,597
Number of Options, Options exercisable		4,388,343
Weighted-Average Exercise Price, Outstanding, Beginning Balance \| $ / shares		$ 14.35
Weighted-Average Exercise Price, Granted \| $ / shares		8.76
Weighted-Average Exercise Price, Exercised \| $ / shares		6.00
Weighted-Average Exercise Price, Forfeited \| $ / shares		11.27
Weighted-Average Exercise Price, Expired \| $ / shares		14.35
Weighted-Average Exercise Price, Outstanding, Ending Balance \| $ / shares		$ 13.25

Business

6 Months Ended

Jun. 30, 2023

Business.

Business

1. Business

Cara Therapeutics, Inc., or the Company, is a commercial-stage biopharmaceutical corporation formed on July 2, 2004. The Company is leading a new treatment paradigm to improve the lives of patients suffering from pruritus. The Company’s primary activities to date have been organizing and staffing the Company, developing its lead product and product candidates, including conducting preclinical studies and clinical trials of difelikefalin-based product candidates, and raising capital.

In August 2021, the Company received U.S. Food and Drug Administration, or FDA, approval for KORSUVA®(difelikefalin) injection, or KORSUVA injection, for the treatment of moderate-to-severe pruritus associated with chronic kidney disease in adults undergoing hemodialysis. Commercial launch of KORSUVA injection began in the United States in April 2022 and the Company began recording the associated profit-sharing revenues in the second quarter of 2022.

In April 2022, the European Commission granted marketing authorization to difelikefalin injection under the brand name Kapruvia® (difelikefalin), or Kapruvia, for the treatment of moderate-to-severe pruritus associated with chronic kidney disease in adult hemodialysis patients. The marketing authorization approved Kapruvia for use in all member states of the European Union, or EU, as well as Iceland, Liechtenstein, and Norway. Kapruvia was also approved in the United Kingdom in April 2022. Commercial launches in Austria, Germany, Sweden, France, the Netherlands, and Finland have commenced. In August 2022, as part of the Access Consortium, difelikefalin injection was approved in Switzerland under the brand name Kapruvia, as well as Singapore and Canada under the brand name KORSUVA. Commercial launch in Switzerland has also commenced. In November 2022, difelikefalin injection was approved in the last Access Consortium country, Australia, under the brand name KORSUVA. Difelikefalin injection was also approved in the United Arab Emirates, Kuwait, and Israel under the brand name KORSUVA in January 2023, May 2023, and June 2023, respectively. The Company expects additional commercial launches to commence over the next 12-18 months.

In 2018, the Company entered into a license and collaboration agreement with a joint venture between Vifor Pharma Group and Fresenius Medical Care Renal Pharmaceutical Ltd., or Vifor Fresenius Medical Care Renal Pharma Ltd., that provides full commercialization rights of Kapruvia, and where applicable KORSUVA, to Vifor Fresenius Medical Care Renal Pharma Ltd. worldwide (excluding the United States, Japan and South Korea). In markets outside of the United States, the Company is eligible to receive tiered double-digit royalty payments based on annual net sales, as defined in the agreement with Vifor Fresenius Medical Care Renal Pharma Ltd., of difelikefalin injection in the licensed territories. In the U.S. market, the agreement with Vifor Fresenius Medical Care Renal Pharma Ltd. provides that Vifor Fresenius Medical Care Renal Pharma Ltd. will promote difelikefalin injection in the dialysis clinics of Fresenius Medical Care North America, or FMCNA, under a profit-sharing arrangement, whereby the Company is generally entitled to 50% of the annual net profits (as defined in the agreement with Vifor Fresenius Medical Care Renal Pharma Ltd.) based on net FMCNA clinic sales (as defined in the agreement with Vifor Fresenius Medical Care Renal Pharma Ltd.) and Vifor Fresenius Medical Care Renal Pharma Ltd. is entitled to 50% of such net profits, subject to potential adjustments in a calendar year based on certain conditions (see Note 11, Collaboration and Licensing Agreements).

In 2020, the Company entered into a second licensing and collaboration agreement, along with stock purchase agreements, with Vifor (International) Ltd., or Vifor International, that provides full commercialization rights of KORSUVA injection to Vifor International in dialysis clinics in the United States under a profit-sharing arrangement, whereby total net sales of KORSUVA injection in the United States, as recorded by Vifor International, are reduced by Vifor International’s cost of goods sold, or COGS, as well as a marketing and distribution fee owed by the Company based on the level of annual net sales, and the resulting amount is shared according to a 60% (Company)/40% (Vifor International) profit split (excluding sales to Fresenius Medical Center dialysis clinics, compensation for which is

governed by the agreement with Vifor Fresenius Medical Care Renal Pharma Ltd.), subject to potential temporary adjustment in future years based on certain conditions (see Note 11, Collaboration and Licensing Agreements).

In May 2022, Vifor International assigned its rights and obligations under the license agreement and a supply agreement, as permitted under the agreements, to Vifor Fresenius Medical Care Renal Pharma Ltd. The Company’s rights and obligations under these agreements were unaffected by this assignment and the assignment did not affect the Company’s economic rights under the agreements with Vifor International.

In August 2022, Vifor Pharma Group (which includes Vifor International) was acquired by CSL Limited and subsequently renamed CSL Vifor as part of the acquisition. The acquisition of Vifor Pharma Group did not affect any of the Company’s rights and obligations pursuant to these agreements.

The Company also has a license agreement with Maruishi Pharmaceutical Co. Ltd., or Maruishi, under which the Company granted Maruishi an exclusive license to develop, manufacture, and commercialize drug products containing difelikefalin for acute pain and/or uremic pruritus in Japan. In September 2022, Maruishi submitted a New Drug Application in Japan for approval of difelikefalin injection for the treatment of pruritus in hemodialysis patients (see Note 11, Collaboration and Licensing Agreements).

As of June 30, 2023, the Company had raised aggregate net proceeds of approximately $519,600 from several rounds of equity financing, including its initial public offering, or IPO, which closed in February 2014 and four follow-on public offerings of common stock, which closed in July 2019, July 2018, April 2017 and August 2015, respectively, and the issuance of convertible preferred stock and debt prior to the IPO. Including profit share revenue and royalties, the Company has also earned approximately $279,900 under its license and supply agreements for difelikefalin, primarily with CSL Vifor, Maruishi, and Chong Kun Dang Pharmaceutical Corp., or CKDP, and an earlier product candidate for which development efforts ceased in 2007. The Company has also received aggregate net proceeds of approximately $98,000 from the issuance and sale of the Company’s common stock to Vifor International in connection with the Company’s licensing agreement with CSL Vifor (see Note 11, Collaboration and Licensing Agreements).

As of June 30, 2023, the Company had unrestricted cash and cash equivalents and marketable securities of $101,744 and an accumulated deficit of $624,376. The Company has incurred substantial net losses and negative cash flows from operating activities in nearly every fiscal period since inception and expects this trend to continue for the foreseeable future. The Company recognized net losses of $31,479 and $4,206 for the three months ended June 30, 2023 and 2022, respectively, and $58,144 and $31,955 for the six months ended June 30, 2023 and 2022, respectively, and had net cash used in operating activities of $55,063 and $30,028 for the six months ended June 30, 2023 and 2022, respectively.

The Company is subject to risks common to other life science companies including, but not limited to, uncertainty of product development and commercialization, lack of marketing and sales history, development by its competitors of new technological innovations, dependence on key personnel, market acceptance of products, product liability, protection of proprietary technology, ability to raise additional financing, and compliance with FDA and other government regulations. If the Company does not successfully commercialize KORSUVA injection, Kapruvia or any of its other product candidates, it will be unable to generate additional recurring product revenue or achieve profitability.

CONDENSED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Common Stock	Additional Paid-In Capital	Accumulated Deficit	Accumulated Other Comprehensive Loss	Total
Balance, Value at Dec. 31, 2021	$ 53	$ 708,585	$ (480,758)	$ (358)	$ 227,522
Balance, Shares at Dec. 31, 2021	53,480,812
Stock-based compensation expense		4,266			4,266
Shares issued upon exercise of stock options, value		3			3
Shares issued upon exercise of stock options, shares	470
Shares issued upon vesting of restricted stock units, value		1,438			1,438
Shares issued upon vesting of restricted stock units, shares	109,943
Net loss			(27,749)		(27,749)
Other comprehensive income (loss)				(1,365)	(1,365)
Balance, Value at Mar. 31, 2022	$ 53	714,292	(508,507)	(1,723)	204,115
Balance, Shares at Mar. 31, 2022	53,591,225
Balance, Value at Dec. 31, 2021	$ 53	708,585	(480,758)	(358)	227,522
Balance, Shares at Dec. 31, 2021	53,480,812
Net loss					(31,955)
Other comprehensive income (loss)				(1,689)
Balance, Value at Jun. 30, 2022	$ 53	719,129	(512,713)	(2,047)	204,422
Balance, Shares at Jun. 30, 2022	53,710,300
Balance, Value at Mar. 31, 2022	$ 53	714,292	(508,507)	(1,723)	204,115
Balance, Shares at Mar. 31, 2022	53,591,225
Stock-based compensation expense		4,232			4,232
Shares issued upon exercise of stock options, value		182			182
Shares issued upon exercise of stock options, shares	30,000
Shares issued upon vesting of restricted stock units, value		423			423
Shares issued upon vesting of restricted stock units, shares	89,075
Net loss			(4,206)		(4,206)
Other comprehensive income (loss)				(324)	(324)
Balance, Value at Jun. 30, 2022	$ 53	719,129	(512,713)	(2,047)	204,422
Balance, Shares at Jun. 30, 2022	53,710,300
Balance, Value at Dec. 31, 2022	$ 53	726,630	(566,232)	(1,672)	158,779
Balance, Shares at Dec. 31, 2022	53,797,341
Stock-based compensation expense		2,972			2,972
Shares issued upon exercise of stock options, value	$ 1	559			560
Shares issued upon exercise of stock options, shares	93,218
Shares issued upon vesting of restricted stock units, value		381			381
Shares issued upon vesting of restricted stock units, shares	83,793
Net loss			(26,665)		(26,665)
Other comprehensive income (loss)				571	571
Balance, Value at Mar. 31, 2023	$ 54	730,542	(592,897)	(1,101)	136,598
Balance, Shares at Mar. 31, 2023	53,974,352
Balance, Value at Dec. 31, 2022	$ 53	726,630	(566,232)	(1,672)	$ 158,779
Balance, Shares at Dec. 31, 2022	53,797,341
Shares issued upon exercise of stock options, shares					93,218
Net loss					$ (58,144)
Other comprehensive income (loss)				942
Balance, Value at Jun. 30, 2023	$ 54	733,984	(624,376)	(730)	108,932
Balance, Shares at Jun. 30, 2023	54,068,806
Balance, Value at Mar. 31, 2023	$ 54	730,542	(592,897)	(1,101)	136,598
Balance, Shares at Mar. 31, 2023	53,974,352
Stock-based compensation expense		3,116			3,116
Shares issued upon vesting of restricted stock units, value		326			326
Shares issued upon vesting of restricted stock units, shares	94,454
Net loss			(31,479)		(31,479)
Other comprehensive income (loss)				371	371
Balance, Value at Jun. 30, 2023	$ 54	$ 733,984	$ (624,376)	$ (730)	$ 108,932
Balance, Shares at Jun. 30, 2023	54,068,806

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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Revenue Recognition - Disaggregation of Revenue (Detail) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		6 Months Ended
	Jan. 31, 2022	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Disaggregation of Revenue [Line Items]
Total revenue		$ 6,933	$ 23,003	$ 13,098	$ 27,793
License and milestone fees
Disaggregation of Revenue [Line Items]
Total revenue			15,000		15,000
License and milestone fees \| Vifor Fresenius Medical Care Renal Pharma Ltd. [Member]
Disaggregation of Revenue [Line Items]
Total revenue			15,000		15,000
Collaborative revenue
Disaggregation of Revenue [Line Items]
Total revenue		5,410	8,003	8,160	8,003
Collaborative revenue \| CSL Vifor Profit Sharing [Member]
Disaggregation of Revenue [Line Items]
Total revenue		5,410	8,003	8,160	8,003
Commercial supply revenue
Disaggregation of Revenue [Line Items]
Total revenue		1,400		4,591	4,790
Commercial supply revenue \| CSL Vifor [Member]
Disaggregation of Revenue [Line Items]
Total revenue		1,400		4,591	4,790
Commercial Supply Revenue With No Associated Costs Of Goods Sold [Member] \| CSL Vifor [Member]
Disaggregation of Revenue [Line Items]
Total revenue	$ 2,295		0
Clinical compound revenue
Disaggregation of Revenue [Line Items]
Total revenue				99
Clinical compound revenue \| Maruishi Pharmaceutical Co., Ltd. [Member]
Disaggregation of Revenue [Line Items]
Total revenue		0	0	99	0
Royalty revenue
Disaggregation of Revenue [Line Items]
Total revenue		123		248
Royalty revenue \| CSL Vifor [Member]
Disaggregation of Revenue [Line Items]
Total revenue			$ 0		$ 0
Royalty revenue \| CSL Vifor [Member] \| CSL Vifor Kapruvia [Member]
Disaggregation of Revenue [Line Items]
Total revenue		$ 123		$ 248

Collaboration and Licensing Agreements

6 Months Ended

Jun. 30, 2023

Collaboration and Licensing Agreements.

Collaboration and Licensing Agreements

11. Collaboration and Licensing Agreements

Vifor (International) Ltd. (Vifor International)

In October 2020, the Company entered into a license agreement with Vifor International, or Vifor Agreement No. 1, under which the Company granted Vifor International an exclusive license solely in the United States to use, distribute, offer for sale, promote, sell and otherwise commercialize difelikefalin injection for all therapeutic uses relating to the inhibition, prevention or treatment of itch associated with pruritus in hemodialysis and peritoneal dialysis patients in the United States. Under Vifor Agreement No. 1, the Company retains all rights with respect to the clinical development of, and activities to gain regulatory approvals of, difelikefalin injection in the United States.

After the assignment of rights of Vifor Agreement No. 1 from Vifor International to Vifor Fresenius Medical Care Renal Pharma Ltd. in May 2022, Vifor Agreement No. 1 provides full commercialization rights in dialysis clinics to CSL Vifor in the United States under a profit-sharing arrangement. Pursuant to the profit-sharing arrangement, the Company is generally entitled to 60% of the net profits (as defined in Vifor Agreement No. 1) from sales of difelikefalin injection in the United States and CSL Vifor is entitled to 40% of such net profits (excluding sales to Fresenius Medical Center dialysis clinics, compensation for which is governed by Vifor Agreement No. 2, as defined below), subject to potential temporary adjustment in future years based on certain conditions. Under Vifor Agreement No. 1, in consideration of CSL Vifor’s conduct of the marketing, promotion, selling and distribution of difelikefalin injection in the United States, the Company pays a marketing and distribution fee to CSL Vifor based on the level of annual net sales. This fee as well as CSL Vifor’s COGS are deducted from net sales in calculating the net profits that are subject to the profit-sharing arrangement under Vifor Agreement No. 1.

In addition, pursuant to Vifor Agreement No. 1, the Company is eligible to receive payments of up to $240,000 upon the achievement of certain sales-based milestones.

The Company retains the rights to make and have made difelikefalin injection, or the Licensed Product, on a non-exclusive basis, in the United States for commercial sale of the Licensed Product for use in all therapeutic areas to prevent, inhibit or treat itch associated with pruritus in hemodialysis and peritoneal-dialysis patients, or the Field, anywhere in the world and for supply of Licensed Product to CSL Vifor under the terms of a supply agreement, or the Vifor International Supply Agreement, which was executed in September 2021. The supply price is the Company’s COGS, as calculated under GAAP, plus an agreed upon margin. The Vifor International Supply Agreement will co-terminate with Vifor Agreement No. 1. The Company also retains the rights to import, distribute, promote, sell and otherwise commercialize the Licensed Product on an exclusive basis outside of the Field either in or outside of the United States.

The Vifor International Supply Agreement is accounted for as a customer option that is not a material right because the selling price of the Licensed Product under the Vifor International Supply Agreement is the Company’s COGS plus an agreed upon margin, which is commensurate with the “COGS plus” model that the Company would charge other parties under similar agreements (the standalone selling price) and not at a discount. Therefore, the sale of commercial supply to CSL Vifor is not a performance obligation under Vifor Agreement No. 1 but rather the Vifor International Supply Agreement is a separate agreement from Vifor Agreement No. 1. The only performance obligation under the Vifor International Supply Agreement is the delivery of the Licensed Product to CSL Vifor for commercialization.

Vifor Fresenius Medical Care Renal Pharma Ltd.

In May 2018, the Company entered into a license agreement with Vifor Fresenius Medical Care Renal Pharma Ltd., or Vifor Agreement No. 2, under which the Company granted Vifor Fresenius Medical Care Renal Pharma Ltd. an exclusive, royalty-bearing license, or the Vifor License, to seek regulatory approval to commercialize, import, export, use, distribute, offer for sale, promote, sell and otherwise commercialize the Licensed Product in the Field worldwide (excluding the United States, Japan and South Korea), or the Territory.

The Company is eligible to receive from Vifor Fresenius Medical Care Renal Pharma Ltd. additional commercial milestone payments in the aggregate of up to $440,000, all of which are sales related. The Company is also eligible to receive tiered double-digit royalty payments based on annual net sales, as defined in Vifor Agreement No. 2, of difelikefalin injection in the licensed territories. The Company retained full commercialization rights for difelikefalin injection for the treatment of chronic kidney disease associated pruritus in the United States except in the dialysis clinics of FMCNA, where Vifor Fresenius Medical Care Renal Pharma Ltd. will promote difelikefalin injection under a profit-sharing arrangement (as defined in Vifor Agreement No. 2), based on net FMCNA clinic sales (as defined in Vifor Agreement No. 2) and the Company and Vifor Fresenius Medical Care Renal Pharma Ltd. are each entitled to 50% of such net profits, subject to potential adjustments in a calendar year based on certain conditions.

The Company retains the rights to make and have made the Licensed Product in the Territory for commercial sale by Vifor Fresenius Medical Care Renal Pharma Ltd. in the Field in or outside the Territory and for supply of Licensed Product to Vifor Fresenius Medical Care Renal Pharma Ltd. under the terms of a supply agreement, or the Vifor Supply Agreement, which was executed in May 2020. The supply price is the Company’s COGS, as calculated under GAAP, plus an agreed upon margin. The Vifor Supply Agreement will co-terminate with Vifor Agreement No. 2.

The Vifor Supply Agreement is accounted for as a customer option that is not a material right because the selling price of the Licensed Product under the Vifor Supply Agreement is the Company’s COGS plus an agreed upon margin, which is commensurate with the “COGS plus” model that the Company would charge other parties under similar agreements (the standalone selling price) and not at a discount. Therefore, the sale of compound to Vifor Fresenius Medical Care Renal Pharma Ltd. is not a performance obligation under Vifor Agreement No. 2 but rather the Vifor Supply Agreement is a separate agreement from Vifor Agreement No. 2. The only performance obligation under the

Vifor Supply Agreement is the delivery of the Licensed Product to Vifor Fresenius Medical Care Renal Pharma Ltd. for commercialization.

Maruishi Pharmaceutical Co., Ltd. (Maruishi)

In April 2013, the Company entered into a license agreement with Maruishi, or the Maruishi Agreement, under which the Company granted Maruishi an exclusive license to develop, manufacture, and commercialize drug products containing difelikefalin for acute pain and/or uremic pruritus in Japan. Maruishi has the right to grant sub-licenses in Japan, which entitles the Company to receive sub-license fees, net of prior payments made by Maruishi to the Company. Under the Maruishi Agreement, the Company and Maruishi are required to use commercially reasonable efforts, at their own expense, to develop, obtain regulatory approval for and commercialize difelikefalin in the United States and Japan, respectively. In addition, the Company provided Maruishi specific clinical development services for difelikefalin used in Maruishi’s field of use.

Under the terms of the Maruishi Agreement, the Company is eligible to receive milestone payments upon the achievement of defined clinical and regulatory events as well as tiered, low double-digit royalties with respect to any sales of the licensed product sold in Japan by Maruishi, if any, and share in any sub-license fees.

In September 2022, Maruishi submitted a New Drug Application in Japan for approval of difelikefalin injection for the treatment of pruritus in hemodialysis patients.

Chong Kun Dang Pharmaceutical Corporation (CKDP)

In April 2012, the Company entered into a license agreement with CKDP, or the CKDP Agreement, in South Korea, under which the Company granted CKDP an exclusive license to develop, manufacture and commercialize drug products containing difelikefalin in South Korea. The Company and CKDP are each required to use commercially reasonable efforts, at their respective expense, to develop, obtain regulatory approval for and commercialize difelikefalin in the United States and South Korea, respectively.

Under the terms of the CKDP Agreement, the Company is eligible to receive milestone payments upon the achievement of defined clinical and regulatory events as well as tiered royalties, with percentages ranging from the high single digits to the high teens, based on net sales of products containing difelikefalin in South Korea, if any, and share in any sub-license fees.

Net Loss Per Share - Computation of Basic and Diluted Net Loss per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2023	Jun. 30, 2022
Net Loss Per Share
Net loss - basic and diluted	$ (31,479)	$ (26,665)	$ (4,206)	$ (27,749)	$ (58,144)	$ (31,955)
Weighted-average common shares outstanding:
Basic	54,002,988		53,614,668		53,937,875	53,561,161
Diluted	54,002,988		53,614,668		53,937,875	53,561,161
Net loss per share:
Basic	$ (0.58)		$ (0.08)		$ (1.08)	$ (0.60)
Diluted	$ (0.58)		$ (0.08)		$ (1.08)	$ (0.60)

- Definition

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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+ Details

- Definition

The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

+ References

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+ Details

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

+ Details

Stock-Based Compensation - Summary of Assumptions Used in Black-Scholes Option Pricing Model (Detail)	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate, minimum	3.38%	2.83%	3.38%	1.70%
Risk-free interest rate, maximum	3.89%	3.54%	4.22%	3.54%
Expected volatility, minimum	80.30%	77.80%	76.30%	77.80%
Expected volatility, maximum	81.30%	81.50%	81.30%	81.90%
Expected dividend yield	0.00%	0.00%	0.00%	0.00%
Employee and Board of Directors Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life of options (in years)	6 years 3 months	6 years 3 months	6 years 3 months	6 years 3 months

Available-for-Sale Marketable Securities - Additional Information (Detail) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2023 USD ($) position	Dec. 31, 2022 USD ($) position
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale allowance for credit loss \| $	$ 0	$ 0
Available-for-sale unrealized credit losses \| $	$ 0	$ 0
Number of available-for-sale marketable securities in unrealized loss positions	17	35
Total number of positions	22	39
Number of positions of available-for-sale in unrealized loss position for 12 months or greater	17
U.S. Government Agency Obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Number of available-for-sale marketable securities in unrealized loss positions	3
Total number of positions	3
Corporate Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Number of available-for-sale marketable securities in unrealized loss positions	8
Total number of positions	8
Municipal Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Number of available-for-sale marketable securities in unrealized loss positions	6
Total number of positions	11

Commitments and Contingencies

6 Months Ended

Jun. 30, 2023

Commitments and Contingencies

Commitments and Contingencies

16. Commitments and Contingencies

License Agreement with Enteris Biopharma, Inc.

In August 2019, the Company entered into a non-exclusive license agreement, or the Enteris License Agreement, with Enteris Biopharma, Inc., or Enteris, pursuant to which Enteris granted to the Company a non-exclusive, royalty-bearing license, including the right to grant sublicenses, under certain proprietary technology and patent rights related to or covering formulations for oral delivery of peptide active pharmaceutical ingredients with functional excipients to enhance permeability and/or solubility, known as Enteris’s Peptelligence^® technology, to develop, manufacture and commercialize products using such technology worldwide, excluding Japan and South Korea.

The Company is also obligated, pursuant to the Enteris License Agreement, to pay Enteris (1) milestone payments upon the achievement of certain development, regulatory and commercial milestones and (2) low-single digit royalty percentages on net sales of licensed products, subject to reductions in specified circumstances. During the three and six

months ended June 30, 2023 and 2022, no milestone payments or royalties were paid to Enteris by the Company in relation to the Enteris License Agreement.

Manufacturing Agreements

In July 2021, the Company entered into an API Commercial Supply Agreement with Polypeptide Laboratories S.A., or PPL, that defines each party’s responsibilities with respect to PPL’s manufacture and supply of the active pharmaceutical ingredient difelikefalin, or API, for the difelikefalin injection product candidate. Under the API Commercial Supply Agreement, PPL shall manufacture API at its facility for sale and supply to the Company, in the amounts as set forth in purchase orders to be provided by the Company. The Company will be required to purchase its requirements of API for each year of the term of the agreement, based on internal forecasts.

The API Commercial Supply Agreement will continue until the fifth anniversary of the approval by the FDA of the new drug application for KORSUVA injection, unless the API Commercial Supply Agreement is earlier terminated, and will automatically be extended for successive five-year periods unless either party gives notice to the other party of its intention to terminate.

In July 2019, the Company entered into a Master Manufacturing Services Agreement, or MSA, with Patheon UK Limited, or Patheon. The MSA governs the general terms under which Patheon, or one of its affiliates, will provide non-exclusive manufacturing services to the Company for the drug products specified by the Company from time to time. Pursuant to the MSA, the Company has agreed to order from Patheon at least a certain percentage of its commercial requirements for a product under a related Product Agreement. Each Product Agreement that the Company may enter into from time to time will be governed by the terms of the MSA, unless expressly modified in such Product Agreement.

In July 2019, the Company entered into two related Product Agreements under the MSA, one with each of Patheon and Patheon Manufacturing Services LLC, or Patheon Greenville, to govern the terms and conditions of the manufacture of commercial supplies of difelikefalin injection, the Company’s lead product candidate. Pursuant to the Product Agreements, Patheon and Patheon Greenville will manufacture commercial supplies of difelikefalin injection at the Monza, Italy and Greenville, North Carolina manufacturing sites, respectively, from active pharmaceutical ingredient supplied by the Company. Patheon and Patheon Greenville will be responsible for supplying the other required raw materials and packaging components, and will also provide supportive manufacturing services such as quality control testing for raw materials, packaging components and finished product.

Leases (Original Corporate Headquarters in 2015 & Amendment for Additional Space in 2020)

Lease expense is recognized on a straight-line basis over the lease term of the Company’s lease agreements for its original headquarters, and additional office space, in Stamford, Connecticut. As a result, $406 and $813 of operating lease cost, or lease expense, was recognized for the three and six months ended June 30, 2023, respectively, consisting of $284 relating to R&D lease expense and $122 relating to G&A lease expense for the three months ended June 30, 2023, and $569 relating to R&D lease expense and $244 relating to G&A lease expense for the six months ended June 30, 2023. For the three and six months ended June 30, 2022, $406 and $812, respectively, of lease expense was recognized, consisting of $284 relating to R&D lease expense and $122 relating to G&A lease expense for the three months ended June 30, 2022, and $568 relating to R&D lease expense and $244 relating to G&A lease expense for the six months ended June 30, 2022.

Lease (New Corporate Headquarters in May 2023)

On May 11, 2023, the Company entered into the New Lease for the Company’s new principal executive offices. The initial term of the New Lease commences on the earlier to occur of (a) the date the Company first occupies the premises for the regular conduct of its business therein, and (b) the date the Landlord delivers the premises to the Company in the condition required under the terms of the New Lease, provided that such date shall be no sooner than November 1, 2023, or the Commencement Date, and will expire on the last day of the calendar month in which occurs the tenth anniversary of the Rent Commencement Date, as defined below, or the Term.

The annual fixed rent rate under the New Lease will initially be $1.3 million (considered by the Company to be at market rate as of the signing of the New Lease), commencing on the date which is the later to occur of (a) the date which is 12 months after the Commencement Date and (b) November 1, 2024, or the Rent Commencement Date, and will increase 2.5% annually thereafter.

The Company will also be responsible for the payment of Additional Rent, as defined in the New Lease, including its share of the operating and tax expenses for the building. As a result, the New Lease contains both a lease and non-lease component which are accounted for separately. The Company allocates the consideration to the lease and non-lease component on a relative standalone price basis.

The Company will have the option to extend the Term under the New Lease for an additional five years on the same terms and conditions (other than with respect to the annual fixed rent at the annual fair market rental rate, as defined in the New Lease) as set forth in the New Lease. This renewable is not included as part of the lease term as defined in ASC 842 since it is not reasonably certain that the Company will exercise that option on the Commencement Date.

On the Commencement Date (or sooner if the Company obtains control of the premises beforehand), the Company will record a lease liability and a right-of-use asset for the New Lease.

Other information related to the existing leases was as follows (information related to the New Lease entered into in May 2023 is not included below and will not be included until the Commencement Date):


	Three Months Ended June 30,						Six Months Ended June 30,
	2023			2022			2023			2022
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash outflows relating to operating leases	$	496		$	487		$	990		$	972
ROU assets obtained in exchange for new operating lease liabilities	$	—		$	—		$	—		$	—
Remaining lease term - operating leases (years)		0.5			1.5			0.5			1.5
Discount rate - operating leases		7.0	%		7.0	%		7.0	%		7.0	%

Future minimum lease payments under non-cancellable operating leases, as well as a reconciliation of these undiscounted cash flows to the operating lease liabilities as of June 30, 2023, were as follows (information related to the New Lease entered into in May 2023 is not included below and will not be included until the Commencement Date):


Year Ending December 31,
2023 (Excluding the six months ended June 30, 2023)	$	1,002
Total future minimum lease payments, undiscounted		1,002
Less imputed interest		(20)
Total	$	982

Operating lease liabilities reported as of June 30, 2023:
Operating lease liabilities - current	$	982
Operating lease liabilities - non-current		—
Total	$	982

Fair Value Measurements

6 Months Ended

Jun. 30, 2023

Fair Value Measurements

Fair Value Measurements

5. Fair Value Measurements

As of June 30, 2023 and December 31, 2022, the Company’s financial instruments consisted of cash, cash equivalents, available-for-sale marketable securities, accounts receivable, net – related party, prepaid expenses, restricted cash, accounts payable and accrued liabilities. The fair values of cash, cash equivalents, accounts receivable, net – related party, prepaid expenses, restricted cash, accounts payable and accrued liabilities approximate their carrying values due to the short-term nature of these financial instruments. Available-for-sale marketable securities are reported at their fair values, based upon pricing of securities with the same or similar investment characteristics as provided by third-party pricing services.

The Company validates the prices provided by its third-party pricing services by reviewing their pricing methods, obtaining market values from other pricing sources, and comparing them to the share prices presented by the third-party pricing services. After completing its validation procedures, the Company did not adjust or override any fair value measurements provided by its third-party pricing services as of June 30, 2023 or December 31, 2022.

The following tables summarize the Company’s financial assets measured at fair value on a recurring basis as of June 30, 2023 and December 31, 2022.

Fair value measurement as of June 30, 2023:


			Quoted prices in		Significant other		Significant
Financial assets			active markets for		observable		unobservable
			identical assets		inputs		inputs
Type of Instrument	Total		(Level 1)		(Level 2)		(Level 3)
Cash and cash equivalents:
Money market funds and checking accounts	$	58,249	$	58,249	$	—	$	—
Available-for-sale marketable securities:
U.S. government agency obligations		9,003		—		9,003		—
Corporate bonds		19,675		—		19,675		—
Municipal bonds		14,817		—		14,817		—
Restricted cash:
Commercial money market account		1,908		1,908		—		—
Total financial assets	$	103,652	$	60,157	$	43,495	$	—

Fair value measurement as of December 31, 2022:


			Quoted prices in		Significant other		Significant
Financial assets			active markets for		observable		unobservable
			identical assets		inputs		inputs
Type of Instrument	Total		(Level 1)		(Level 2)		(Level 3)
Cash and cash equivalents:
Money market funds and checking accounts	$	63,741	$	63,741	$	—	$	—
Available-for-sale marketable securities:
U.S. government agency obligations		8,877		—		8,877		—
Corporate bonds		35,185		—		35,185		—
Commercial paper		26,875		—		26,875		—
Municipal bonds		22,071		—		22,071		—
Restricted cash:
Commercial money market account		408		408		—		—
Total financial assets	$	157,157	$	64,149	$	93,008	$	—

There were no purchases, sales or maturities of Level 3 financial assets and no unrealized gains or losses related to Level 3 available-for-sale marketable securities during each of the three and six months ended June 30, 2023 and 2022. There were no transfers of financial assets into or out of Level 3 classification during each of the three and six months ended June 30, 2023 and 2022.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

CONDENSED STATEMENTS OF COMPREHENSIVE LOSS - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Revenue:
Total revenue	$ 6,933	$ 23,003	$ 13,098	$ 27,793
Operating expenses:
Cost of goods sold	1,418		4,008	2,081
Research and development	30,310	19,905	54,644	41,178
General and administrative	7,545	7,570	14,436	16,917
Total operating expenses	39,273	27,475	73,088	60,176
Operating loss	(32,340)	(4,472)	(59,990)	(32,383)
Other income, net	861	266	1,846	428
Net loss	$ (31,479)	$ (4,206)	$ (58,144)	$ (31,955)
Net loss per share:
Basic	$ (0.58)	$ (0.08)	$ (1.08)	$ (0.60)
Diluted	$ (0.58)	$ (0.08)	$ (1.08)	$ (0.60)
Weighted average shares:
Basic	54,002,988	53,614,668	53,937,875	53,561,161
Diluted	54,002,988	53,614,668	53,937,875	53,561,161
Other comprehensive income (loss), net of tax of $0:
Change in unrealized gains (losses) on available-for-sale marketable securities	$ 371	$ (324)	$ 942	$ (1,689)
Total comprehensive loss	(31,108)	(4,530)	(57,202)	(33,644)
Collaborative revenue
Revenue:
Total revenue	5,410	8,003	8,160	8,003
Commercial supply revenue
Revenue:
Total revenue	1,400		4,591	4,790
Royalty revenue
Revenue:
Total revenue	$ 123		248
License and milestone fees
Revenue:
Total revenue		$ 15,000		$ 15,000
Clinical compound revenue
Revenue:
Total revenue			$ 99

Accumulated Other Comprehensive Loss - Summary of Changes in Accumulated Other Comprehensive (Loss) Income, Net of Tax, from Unrealized Gains (Losses) on Available-for-Sale Marketable Securities (Detail) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2023	Jun. 30, 2022
Accumulated Other Comprehensive Income Loss [Line Items]
Balance, Value	$ 136,598	$ 158,779	$ 204,115	$ 227,522	$ 158,779	$ 227,522
Amount reclassified from accumulated other comprehensive loss	0		0		0	0
Net current period other comprehensive income (loss)	371	571	(324)	(1,365)
Balance, Value	108,932	136,598	204,422	204,115	108,932	204,422
Accumulated Other Comprehensive Loss
Accumulated Other Comprehensive Income Loss [Line Items]
Balance, Value	(1,101)	(1,672)	(1,723)	(358)	(1,672)	(358)
Other comprehensive loss before reclassifications					942	(1,689)
Net current period other comprehensive income (loss)	371	571	(324)	(1,365)	942	(1,689)
Balance, Value	$ (730)	$ (1,101)	$ (2,047)	$ (1,723)	$ (730)	$ (2,047)

- Definition

Amount after tax and reclassification adjustments of other comprehensive income (loss).

Related Party Transactions

6 Months Ended

Jun. 30, 2023

Related Party Transactions

Related Party Transactions

17. Related Party Transactions

As of June 30, 2023, Vifor International owned 7,396,770, or 13.7%, of the Company’s common stock. CSL Vifor and its affiliates are considered related parties as of June 30, 2023 and December 31, 2022 (see Note 11, Collaboration and Licensing Agreements).

As of June 30, 2023 and December 31, 2022, amounts due from CSL Vifor of $10,124 and $3,260, respectively, primarily relating to the Company’s share of the profit generated by sales of KORSUVA injection in the United States by CSL Vifor, its commercial supply of KORSUVA injection to CSL Vifor, and royalty revenue from CSL Vifor relating to sales of Kapruvia outside of the United States were included within accounts receivable, net – related party.

The Company’s collaborative revenue of $5,410 and $8,160 from its share of the profit generated by sales of KORSUVA injection in the United States by CSL Vifor was included within collaborative revenue for the three and six months ended June 30, 2023, respectively. The Company’s collaborative revenue of $8,003 from its share of the profit generated by sales of KORSUVA injection in the United States by CSL Vifor was included within collaborative revenue for each of the three and six months ended June 30, 2022.

Sales of KORSUVA injection to CSL Vifor of $1,400 and $4,591 were included within commercial supply revenue for the three and six months ended June 30, 2023, respectively. The associated COGS for the Company’s commercial supply revenue from CSL Vifor was $1,418 and $4,008 for the three and six months ended June 30, 2023, respectively. Sales of KORSUVA injection to CSL Vifor of $4,790 was also included within commercial supply revenue for the six months ended June 30, 2022, with an associated COGS for the Company’s commercial supply revenue from CSL Vifor of $2,081.

The Company recorded $15,000 as license and milestone fee revenue from Vifor Fresenius Medical Care Renal Pharma Ltd. for the three and six months ended June 30, 2022, as a result of the European Commission’s regulatory approval of Kapruvia in April 2022.

The Company recorded $123 and $248 as royalty revenue based on net sales of Kapruvia outside of the United States during the three and six months ended June 30, 2023.

Prepaid Expenses - Additional Information (Detail) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Prepaid expenses
Prepaid expenses	$ 14,976	$ 16,267
Prepaid R&D clinical costs	12,561	15,188
Prepaid insurance	1,400	543
Other prepaid costs	$ 1,015	$ 536

Available-for-Sale Marketable Securities - Schedule of Fair Values and Continuous Unrealized Loss Positions of Available-for-Sale Marketable Securities (Detail) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale marketable securities, continuous unrealized loss position, Less than 12 Months, Fair Value		$ 18,358
Available-for-sale marketable securities, continuous unrealized loss position, Less than 12 Months, Gross Unrealized Losses		(48)
Available-for-sale marketable securities, continuous unrealized loss position, 12 Months or Greater, Fair Value	$ 36,380	62,181
Available-for-sale marketable securities, continuous unrealized loss position, 12 Months or Greater, Gross Unrealized Losses	(730)	(1,626)
Available-for-sale marketable securities, continuous unrealized loss position, Fair Value	36,380	80,539
Available-for-sale marketable securities, continuous unrealized loss position, Gross Unrealized Losses	(730)	(1,674)
U.S. Government Agency Obligations [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale marketable securities, continuous unrealized loss position, 12 Months or Greater, Fair Value	9,003	8,877
Available-for-sale marketable securities, continuous unrealized loss position, 12 Months or Greater, Gross Unrealized Losses	(497)	(623)
Available-for-sale marketable securities, continuous unrealized loss position, Fair Value	9,003	8,877
Available-for-sale marketable securities, continuous unrealized loss position, Gross Unrealized Losses	(497)	(623)
Corporate Bonds [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale marketable securities, continuous unrealized loss position, Less than 12 Months, Fair Value		1,470
Available-for-sale marketable securities, continuous unrealized loss position, Less than 12 Months, Gross Unrealized Losses		(26)
Available-for-sale marketable securities, continuous unrealized loss position, 12 Months or Greater, Fair Value	19,675	33,715
Available-for-sale marketable securities, continuous unrealized loss position, 12 Months or Greater, Gross Unrealized Losses	(184)	(617)
Available-for-sale marketable securities, continuous unrealized loss position, Fair Value	19,675	35,185
Available-for-sale marketable securities, continuous unrealized loss position, Gross Unrealized Losses	(184)	(643)
Commercial Paper [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale marketable securities, continuous unrealized loss position, Less than 12 Months, Fair Value		15,906
Available-for-sale marketable securities, continuous unrealized loss position, Less than 12 Months, Gross Unrealized Losses		(6)
Available-for-sale marketable securities, continuous unrealized loss position, Fair Value		15,906
Available-for-sale marketable securities, continuous unrealized loss position, Gross Unrealized Losses		(6)
Municipal Bonds [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale marketable securities, continuous unrealized loss position, Less than 12 Months, Fair Value		982
Available-for-sale marketable securities, continuous unrealized loss position, Less than 12 Months, Gross Unrealized Losses		(16)
Available-for-sale marketable securities, continuous unrealized loss position, 12 Months or Greater, Fair Value	7,702	19,589
Available-for-sale marketable securities, continuous unrealized loss position, 12 Months or Greater, Gross Unrealized Losses	(49)	(386)
Available-for-sale marketable securities, continuous unrealized loss position, Fair Value	7,702	20,571
Available-for-sale marketable securities, continuous unrealized loss position, Gross Unrealized Losses	$ (49)	$ (402)

Available-for-Sale Marketable Securities - Schedule of Amortized Cost and Fair Values of Marketable Debt Securities by Contractual Maturity (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022
Debt Securities [Abstract]
Amortized Cost of marketable debt securities, contractual maturity, less than one year	$ 36,725		$ 36,725		$ 82,678
Amortized Cost of marketable debt securities, contractual maturity, One year to two years	7,500		7,500		12,002
Amortized cost	44,225		44,225		94,680
Fair value of marketable debt securities, contractual maturities, less than one year	36,442		36,442		81,658
Fair value of marketable debt securities, contractual maturity, One year to two years	7,053		7,053		11,350
Total fair Value of marketable debt securities, contractual maturity	43,495		43,495		93,008
Proceeds from sale of available-for-sale marketable securities	0	$ 0	0	$ 0
Interest receivable	$ 420		$ 420		$ 489

Inventory, net (Tables)

6 Months Ended

Jun. 30, 2023

Inventory, net

Schedule of Inventory, net

Inventory, net consists of the following:


	June 30, 2023		December 31, 2022
Raw materials	$	2,571	$	1,918
Work-in-process		863		499
		3,434		2,417
Less Inventory Reserve for Obsolescence		(14)		(34)
Total	$	3,420	$	2,383

Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Income Taxes
Company's effective tax rate	0.00%	0.00%	0.00%	0.00%
Percentage of ineligible annual research and development credit for cash	65.00%	65.00%	65.00%	65.00%
Income tax benefit	$ 0	$ 0	$ 0	$ 0
Income tax receivable related to R&D credit	$ 697		$ 697

- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References + Details

Accumulated Other Comprehensive Loss (Tables)

6 Months Ended

Jun. 30, 2023

Accumulated Other Comprehensive Loss

Summary of Changes in Accumulated Other Comprehensive (Loss) Income, Net of Tax, from Unrealized Gains (Losses) on Available-for-Sale Marketable Securities


	Total Accumulated
	Other Comprehensive
	Loss
Balance, December 31, 2022	$	(1,672)
Other comprehensive income before reclassifications		942
Amount reclassified from accumulated other comprehensive loss		—
Net current period other comprehensive income		942
Balance, June 30, 2023	$	(730)

Balance, December 31, 2021	$	(358)
Other comprehensive loss before reclassifications		(1,689)
Amount reclassified from accumulated other comprehensive loss		—
Net current period other comprehensive loss		(1,689)
Balance, June 30, 2022	$	(2,047)

Stock-Based Compensation (Tables)

6 Months Ended

Jun. 30, 2023

Summary of Assumptions Used in Black-Scholes Option Pricing Model


	Three Months Ended		Six Months Ended
	June 30,		June 30,
	2023	2022	2023	2022
Risk-free interest rate	3.38% - 3.89%	2.83% - 3.54%	3.38% - 4.22%	1.70% - 3.54%
Expected volatility	80.3% - 81.3%	77.8% - 81.5%	76.3% - 81.3%	77.8% - 81.9%
Expected dividend yield	0%	0%	0%	0%
Expected life of employee and Board options (in years)	6.25	6.25	6.25	6.25

Summary of Compensation Expense Relating to Stock Options


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2023		2022		2023		2022
Research and development	$	1,447	$	1,744	$	2,927	$	3,661
General and administrative		1,434		1,958		2,675		3,988
Total stock option expense	$	2,881	$	3,702	$	5,602	$	7,649

Summary of Stock Option Activity


		Weighted
	Number of	Average Exercise
	Shares	Price
Outstanding, December 31, 2022	7,689,449	$	14.35
Granted	1,798,921		8.76
Exercised	(93,218)		6.00
Forfeited	(117,629)		11.27
Expired	(1,142,926)		14.35
Outstanding, June 30, 2023	8,134,597	$	13.25
Options exercisable, June 30, 2023	4,388,343

Employees And Non-Employee Members Of Board Of Directors [Member]

Summary of Restricted Stock Unit Activity


		Weighted
	Number of	Average Grant
	Units	Date Fair Value
Outstanding, December 31, 2022	372,513	$	13.20
Awarded	601,172		7.81
Vested and released	(178,247)		12.15
Forfeited	(3,585)		10.46
Outstanding, June 30, 2023	791,853	$	9.36
Restricted stock units exercisable (vested and deferred), June 30, 2023	—

CONDENSED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 58,249	$ 63,741
Marketable securities	36,442	81,658
Accounts receivable, net - related party	10,124	3,260
Inventory, net	3,420	2,383
Income tax receivable	697	697
Other receivables	420	496
Prepaid expenses	14,976	16,267
Restricted cash	408	408
Total current assets	124,736	168,910
Operating lease right-of-use assets	792	1,551
Marketable securities, non-current	7,053	11,350
Property and equipment, net	308	426
Restricted cash, non-current	1,500
Total assets	134,389	182,237
Current liabilities:
Accounts payable and accrued expenses	24,475	21,540
Operating lease liabilities, current	982	1,918
Total current liabilities	25,457	23,458
Commitments and contingencies (Note 16)
Stockholders' equity:
Preferred stock; $0.001 par value; 5,000,000 shares authorized at June 30, 2023 and December 31, 2022, zero shares issued and outstanding at June 30, 2023 and December 31, 2022
Common stock; $0.001 par value; 100,000,000 shares authorized at June 30, 2023 and December 31, 2022, 54,068,806 shares and 53,797,341 shares issued and outstanding at June 30, 2023 and December 31, 2022, respectively	54	53
Additional paid-in capital	733,984	726,630
Accumulated deficit	(624,376)	(566,232)
Accumulated other comprehensive loss	(730)	(1,672)
Total stockholders' equity	108,932	158,779
Total liabilities and stockholders' equity	$ 134,389	$ 182,237

Restricted Cash

6 Months Ended

Jun. 30, 2023

Restricted Cash

Restricted Cash

6. Restricted Cash

In May 2023, the Company entered into a lease agreement with 400 Atlantic Joint Venture LLC and SLJ Atlantic Stamford LLC (tenants-in-common), or the Landlord, for the lease of 26,374 square feet of office space located at 400 Atlantic Street, Stamford, Connecticut 06901 for its new principal executive offices, or the New Lease. The Company is required to maintain a stand-by letter of credit as a security deposit under the New Lease and its existing leases for its office spaces in Stamford, Connecticut (refer to Note 16, Commitments and Contingencies: Leases). The fair value of the letters of credit approximates its contract value. The Company’s bank requires the Company to maintain a restricted cash balance to serve as collateral for the letters of credit issued to the landlords by the bank. As of June 30, 2023, the restricted cash balances for the New Lease and the existing leases were invested in a commercial money market account.

As of June 30, 2023, the Company had $408 of restricted cash related to its existing leases in current assets and $1,500 of restricted cash related to the New Lease in long-term assets. After the first and second anniversaries of the rent commencement date, the face amount of the letter of credit relating to the New Lease can be reduced by $500 each period if the Company is not in default of its lease obligations. As of December 31, 2022, the Company had $408 of restricted cash related to its existing leases in current assets.

The following table provides a reconciliation of cash, cash equivalents, and restricted cash reported within the Condensed Balance Sheets that sum to the total of the same such amounts shown in the Condensed Statements of Cash Flows.


	June 30, 2023		December 31, 2022
Cash and cash equivalents	$	58,249	$	63,741
Restricted cash, current assets		408		408
Restricted cash, long-term assets		1,500		—
Total cash, cash equivalents, and restricted cash shown in the Condensed Statements of Cash Flows	$	60,157	$	64,149

Collaboration and Licensing Agreements - Additional Information (Detail) - USD ($) $ in Thousands	1 Months Ended
	Oct. 31, 2020	May 31, 2018	May 17, 2018
Vifor Fresenius Medical Care Renal Pharma Ltd Agreement No 2 [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Percentage of net profit sharing		50.00%
CSL Vifor Maximum [Member] \| Vifor Fresenius Medical Care Renal Pharma Ltd Agreement No 1 [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Potential sales-based milestone payments	$ 240,000
CSL Vifor [Member] \| Vifor Fresenius Medical Care Renal Pharma Ltd Agreement No 1 [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Percentage of net profit sharing	40.00%
CSL Vifor [Member] \| Vifor Fresenius Medical Care Renal Pharma Ltd Agreement No 1 [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Percentage of net profit sharing	60.00%
Vifor Fresenius Medical Care Renal Pharma Ltd Agreement No 2 [Member] \| Maximum [Member] \| Regulatory and Commercial Milestones [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Potential milestone payments			$ 440,000

Stock-Based Compensation - Additional Information (Detail)													1 Months Ended										3 Months Ended				6 Months Ended		12 Months Ended
	Jun. 15, 2023 shares	Jun. 01, 2023 $ / shares shares	Mar. 01, 2023 $ / shares shares	Oct. 12, 2022 $ / shares shares	Jun. 15, 2022 $ / shares shares	Jun. 02, 2022 $ / shares shares	Mar. 31, 2022 shares	Feb. 25, 2022 installment $ / shares shares	Dec. 17, 2021 installment $ / shares shares	Oct. 29, 2021 tranche $ / shares shares	Jun. 03, 2021 $ / shares shares	Mar. 30, 2021 installment $ / shares shares	Jun. 30, 2023 $ / shares shares	Apr. 30, 2023 shares	Feb. 28, 2023 shares	Jan. 31, 2023 shares	Dec. 31, 2022 $ / shares shares	Oct. 31, 2022 shares	Jun. 30, 2022 shares	Mar. 31, 2022 shares	Feb. 28, 2022 shares	Feb. 29, 2020 installment $ / shares shares	Jun. 30, 2023 USD ($) $ / shares shares	Mar. 31, 2023 shares	Jun. 30, 2022 USD ($) $ / shares shares	Mar. 31, 2022 shares	Jun. 30, 2023 USD ($) $ / shares shares	Jun. 30, 2022 USD ($) $ / shares shares	Dec. 31, 2015 shares	Jan. 01, 2023 shares	Nov. 20, 2019 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, par value \| $ / shares													$ 0.001				$ 0.001						$ 0.001				$ 0.001
Common stock, shares outstanding													54,068,806				53,797,341						54,068,806				54,068,806
Common stock, shares issued													54,068,806				53,797,341						54,068,806				54,068,806
Number of restricted stock units outstanding													791,853						648,450				791,853		648,450		791,853	648,450
Number of options outstanding													8,134,597				7,689,449		7,419,027				8,134,597		7,419,027		8,134,597	7,419,027
Options granted																											1,798,921
Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units vested shares																							94,454	83,793	89,075	109,943
Board of Directors Chairman [Member] \| Restricted Stock Units [Member] \| June 2022 \| Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units vested shares																			11,876
Employees [Member] \| Restricted Stock Units [Member] \| Research and Development [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense \| $																							$ 116,000		$ 198,000		$ 295,000	$ 365,000
Employees [Member] \| Restricted Stock Units [Member] \| General and Administrative [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense \| $																							310,000		517,000		639,000	1,969,000
Director [Member] \| Restricted Stock Units [Member] \| General and Administrative [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense \| $																							$ 135,000		$ 238,000		$ 258,000	$ 377,000
Director [Member] \| Time-based Restricted Stock Units [Member] \| June 2022 \| Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of awards granted													1 year						1 year
Restricted stock units vested shares													59,380						43,200
Executive Officers [Member] \| Time-based Restricted Stock Units [Member] \| February 2022 \| Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of awards granted															3 years						3 years
Restricted stock units vested shares															42,920						32,666
Executive Officers [Member] \| Time-based Restricted Stock Units [Member] \| December 2021 \| Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units vested shares													26,199
Executive Officers [Member] \| Time-based Restricted Stock Units [Member] \| October 2021 \| Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units vested shares														8,875		8,875
Executive Officers [Member] \| Time-based Restricted Stock Units [Member] \| March 2021 \| Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of awards granted																								3 years
Restricted stock units vested shares																								15,999
Executive Officers [Member] \| Time-based Restricted Stock Units [Member] \| February 2020 \| Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of awards granted															3 years
Restricted stock units vested shares															15,999
Non-employee Consultants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted																							0		0		0	0
Employees And Non-Employee Members Of Board Of Directors [Member] \| Share-based Payment Arrangement, Employee [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of options granted \| $ / shares																							$ 2.43		$ 6.30		$ 6.18	$ 7.23
2019 Inducement Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, par value \| $ / shares																															$ 0.001
Awarded																							0		0		0	0
2019 Inducement Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, number of shares authorized																															300,000,000
2019 Inducement Plan [Member] \| Share-based Payment Arrangement, Employee [Member] \| Share-Based Compensation Award, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of vested shares on first anniversary of grant date																											25.00%
2019 Inducement Plan [Member] \| Share-based Payment Arrangement, Employee [Member] \| Share-based Compensation Award, Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of awards granted																											36 months
2019 Inducement Plan [Member] \| Share-based Payment Arrangement, Employee [Member] \| Share Based Compensation Subsequent Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of awards granted																											4 years
2014 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock options that may be granted after the tenth anniversary of the 2014 Plan																											0
Annual increases in number of shares reserved for issuance as a percentage of shares of capital stock outstanding through January 1, 2024																													3.00%
Share-based compensation arrangement by share-based payment award, number of shares authorized																	10,589,103													12,203,023
Options granted																							349,767		324,981		1,798,921	1,302,419
2014 Equity Incentive Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Term of awards granted																											10 years
2014 Equity Incentive Plan [Member] \| Maximum [Member] \| Incentive Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, number of shares authorized																													30,000,000
2014 Equity Incentive Plan [Member] \| Board of Directors Chairman [Member] \| Restricted Stock Units [Member] \| General and Administrative [Member] \| June 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense \| $																									$ 100,000			$ 100,000
2014 Equity Incentive Plan [Member] \| Employees [Member] \| Performance Restricted Stock Units [Member] \| February 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awarded								243,000
Restricted stock units, grant date fair value \| $ / shares								$ 10.46
Compensation expense \| $																							$ 0		0		$ 0	0
Number of restricted stock units outstanding													0										0				0
2014 Equity Incentive Plan [Member] \| Employees [Member] \| Performance Restricted Stock Units [Member] \| March 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awarded												176,000
Restricted stock units, grant date fair value \| $ / shares												$ 20.59
Compensation expense \| $																							$ 0				$ 0
Restricted stock units, vested																					37,999
Restricted stock units, forfeited due to performance targets not getting met																				93,999
Number of restricted stock units outstanding													0										0				0
2014 Equity Incentive Plan [Member] \| Employees [Member] \| Performance Restricted Stock Units [Member] \| March 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awarded			407,000
Restricted stock units, grant date fair value \| $ / shares			$ 10.06
Compensation expense \| $																							$ 0				$ 0
Number of restricted stock units outstanding													407,000										407,000				407,000
2014 Equity Incentive Plan [Member] \| Employees [Member] \| Performance Restricted Stock Units [Member] \| General and Administrative [Member] \| Modified November 2021 Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense \| $																												303,000
2014 Equity Incentive Plan [Member] \| Employees [Member] \| Performance Restricted Stock Units [Member] \| General and Administrative [Member] \| March 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense \| $																												729,000
2014 Equity Incentive Plan [Member] \| Employees [Member] \| Time-based Restricted Stock Units [Member] \| February 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of awards granted								3 years
Awarded								145,170
Restricted stock units, grant date fair value \| $ / shares								$ 10.46
Number of equal installment \| installment								3
Compensation expense \| $																							$ 85,000		108,000		$ 199,000	158,000
Restricted stock units, vested															42,920
Number of restricted stock units outstanding													78,665										78,665				78,665
2014 Equity Incentive Plan [Member] \| Employees [Member] \| Time-based Restricted Stock Units [Member] \| December 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of awards granted									18 months
Awarded									63,573
Restricted stock units, grant date fair value \| $ / shares									$ 12.45
Number of equal installment \| installment									2
Compensation expense \| $																							$ 91,000		82,000		$ 199,000	213,000
Restricted stock units, vested	26,199																										0
2014 Equity Incentive Plan [Member] \| Employees [Member] \| Time-based Restricted Stock Units [Member] \| March 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of awards granted												3 years
Awarded												100,000
Restricted stock units, grant date fair value \| $ / shares												$ 20.59
Number of equal installment \| installment												3
Compensation expense \| $																							82,000		196,000		$ 163,000	480,000
Restricted stock units, vested																			17,333	33,336							15,999
Restricted stock units, Forfeited																			17,333
2014 Equity Incentive Plan [Member] \| Employees [Member] \| Time-based Restricted Stock Units [Member] \| February 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of awards granted																						3 years
Awarded																						98,000
Restricted stock units, grant date fair value \| $ / shares																						$ 16.36
Number of equal installment \| installment																						3
Compensation expense \| $																							0		175,000		$ 39,000	394,000
Restricted stock units, vested																					32,666						0
2014 Equity Incentive Plan [Member] \| Employees [Member] \| Time-based Restricted Stock Units [Member] \| Research and Development [Member] \| February 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense \| $																							17,000		47,000		$ 64,000	65,000
2014 Equity Incentive Plan [Member] \| Employees [Member] \| Time-based Restricted Stock Units [Member] \| Research and Development [Member] \| December 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense \| $																							44,000		52,000		96,000	104,000
2014 Equity Incentive Plan [Member] \| Employees [Member] \| Time-based Restricted Stock Units [Member] \| Research and Development [Member] \| March 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense \| $																							55,000		55,000		109,000	109,000
2014 Equity Incentive Plan [Member] \| Employees [Member] \| Time-based Restricted Stock Units [Member] \| Research and Development [Member] \| February 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense \| $																									44,000		26,000	87,000
2014 Equity Incentive Plan [Member] \| Employees [Member] \| Time-based Restricted Stock Units [Member] \| General and Administrative [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense \| $																									131,000
2014 Equity Incentive Plan [Member] \| Employees [Member] \| Time-based Restricted Stock Units [Member] \| General and Administrative [Member] \| Modified February 2020 Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense \| $																									109,000			264,000
2014 Equity Incentive Plan [Member] \| Employees [Member] \| Time-based Restricted Stock Units [Member] \| General and Administrative [Member] \| Modified November 2021 Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense \| $																									114,000			317,000
2014 Equity Incentive Plan [Member] \| Employees [Member] \| Time-based Restricted Stock Units [Member] \| General and Administrative [Member] \| February 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense \| $																							68,000		61,000		135,000	93,000
2014 Equity Incentive Plan [Member] \| Employees [Member] \| Time-based Restricted Stock Units [Member] \| General and Administrative [Member] \| December 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense \| $																							47,000		30,000		103,000	109,000
2014 Equity Incentive Plan [Member] \| Employees [Member] \| Time-based Restricted Stock Units [Member] \| General and Administrative [Member] \| March 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense \| $																							$ 27,000		141,000		54,000	371,000
2014 Equity Incentive Plan [Member] \| Employees [Member] \| Time-based Restricted Stock Units [Member] \| General and Administrative [Member] \| February 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense \| $																											$ 13,000	307,000
2014 Equity Incentive Plan [Member] \| Director [Member] \| Incentive Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of awards granted																											3 years
2014 Equity Incentive Plan [Member] \| Executive Officers [Member] \| Time-based Restricted Stock Units [Member] \| October 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awarded				7,267
Restricted stock units, grant date fair value \| $ / shares				$ 9.42
Number of restricted stock units outstanding													7,267										7,267				7,267
2014 Equity Incentive Plan [Member] \| Executive Officers [Member] \| Time-based Restricted Stock Units [Member] \| March 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units, vested																											15,999
2014 Equity Incentive Plan [Member] \| Executive Officers [Member] \| Time-based Restricted Stock Units [Member] \| February 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units, vested															15,999
2014 Equity Incentive Plan [Member] \| Executive Officers [Member] \| Time-based Restricted Stock Units [Member] \| General and Administrative [Member] \| October 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense \| $																							$ 19,000				$ 38
2014 Equity Incentive Plan [Member] \| Chief Financial Officer [Member] \| Time-based Restricted Stock Units [Member] \| June 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awarded					7,500
Restricted stock units, grant date fair value \| $ / shares					$ 7.94
Compensation expense \| $																									$ 5,000			5,000
Restricted stock units, vested																											0
2014 Equity Incentive Plan [Member] \| Former Chief Financial Officer [Member] \| Performance Restricted Stock Units [Member] \| February 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units, Forfeited																			29,000
Restricted stock units, forfeited due to resignation of former CFO																									20,000
Restricted stock units, cancelled																	214,000
2014 Equity Incentive Plan [Member] \| Former Chief Financial Officer [Member] \| Time-based Restricted Stock Units [Member] \| December 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units, forfeited due to resignation of former CFO																			11,170
2014 Equity Incentive Plan [Member] \| Chief Executive Officer [Member] \| Time-based Restricted Stock Units [Member] \| October 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awarded										147,942
Restricted stock units, grant date fair value \| $ / shares										$ 16.83
Number of restricted stock unit tranches \| tranche										2
Restricted stock units, vested														8,875		8,875		35,500
Number of restricted stock units outstanding													88,750										88,750				88,750
2014 Equity Incentive Plan [Member] \| Chief Executive Officer [Member] \| Time-based Restricted Stock Units [Member] \| General and Administrative [Member] \| October 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense \| $																							$ 149,000		$ 149,000		$ 296,000	355,000
2014 Equity Incentive Plan [Member] \| Chief Executive Officer [Member] \| Share-Based Compensation Award, Tranche One [Member] \| Time-based Restricted Stock Units [Member] \| October 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of vested shares on first anniversary of grant date										25.00%
Awarded										142,000
2014 Equity Incentive Plan [Member] \| Chief Executive Officer [Member] \| Share-based Compensation Award, Tranche Two [Member] \| Time-based Restricted Stock Units [Member] \| October 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of awards granted										36 months
Restricted stock units, vested							5,942
2014 Equity Incentive Plan [Member] \| Employee And Nonemployee Consultants [Member] \| Share-Based Compensation Award, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of vested shares on first anniversary of grant date																											25.00%
2014 Equity Incentive Plan [Member] \| Employee And Nonemployee Consultants [Member] \| Share-based Compensation Award, Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of awards granted																											36 months
2014 Equity Incentive Plan [Member] \| Employee And Nonemployee Consultants [Member] \| Share Based Compensation Subsequent Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of awards granted																											4 years
2014 Equity Incentive Plan [Member] \| Non-employee Directors [Member] \| Restricted Stock Units [Member] \| June 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of awards granted						1 year
Awarded						59,380
Restricted stock units, grant date fair value \| $ / shares						$ 8.42
Number of restricted stock units outstanding													0										0				0
2014 Equity Incentive Plan [Member] \| Non-employee Directors [Member] \| Restricted Stock Units [Member] \| June 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of awards granted											1 year
Awarded											43,200
Restricted stock units, grant date fair value \| $ / shares											$ 13.06
Number of restricted stock units outstanding													0										0				0
2014 Equity Incentive Plan [Member] \| Non-employee Directors [Member] \| Restricted Stock Units [Member] \| June 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of awards granted		1 year
Awarded		194,172
Restricted stock units, grant date fair value \| $ / shares		$ 3.09
Number of restricted stock units outstanding													194,172										194,172				194,172
2014 Equity Incentive Plan [Member] \| Non-employee Directors [Member] \| Restricted Stock Units [Member] \| General and Administrative [Member] \| June 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense \| $																							$ 86,000		38,000		$ 209,000	38,000
2014 Equity Incentive Plan [Member] \| Non-employee Directors [Member] \| Restricted Stock Units [Member] \| General and Administrative [Member] \| June 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense \| $																									$ 100,000			$ 239,000
2014 Equity Incentive Plan [Member] \| Non-employee Directors [Member] \| Restricted Stock Units [Member] \| General and Administrative [Member] \| June 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense \| $																							$ 49,000				$ 49,000
2014 Equity Incentive Plan [Member] \| Employees And Non-Employee Members Of Board Of Directors [Member] \| Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awarded																											601,172
Restricted stock units, grant date fair value \| $ / shares																											$ 7.81
Restricted stock units, vested																											178,247
Restricted stock units, Forfeited																											3,585
Number of restricted stock units outstanding													791,853				372,513						791,853				791,853

Commitments and Contingencies - Schedule of Future Minimum Lease Payments under Non-cancellable Operating Leases, Reconciliation of Undiscounted Cash Flows to the Operating Lease Liability (Detail) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Operating Lease Liabilities, Payments Due [Abstract]
2023 (Excluding the six months ended June 30, 2023)	$ 1,002
Total future minimum lease payments, undiscounted	1,002
Less imputed interest	(20)
Operating lease liabilities	982
Operating lease liabilities reported as of June 30, 2023:
Operating lease liabilities - current	982	$ 1,918
Total	$ 982

Net Loss Per Share

6 Months Ended

Jun. 30, 2023

Net Loss Per Share

Net Loss Per Share

13. Net Loss Per Share

The Company computes basic net income (loss) per share by dividing net income (loss) by the weighted-average number of shares of common stock outstanding. Diluted net income (loss) per share includes the potential dilutive effect of common stock equivalents as if such securities were exercised during the period, when the effect is dilutive. Common stock equivalents may include outstanding stock options or restricted stock units, which are included using the treasury stock method when dilutive. For each of the three and six months ended June 30, 2023 and 2022, the Company excluded the effects of potentially dilutive shares that were outstanding during those respective periods from the denominator as their inclusion would be anti-dilutive due to the Company’s net losses during those periods.

The denominators used in the net loss per share computations are as follows:


	Three Months Ended		Six Months Ended
	June 30,		June 30,
	2023	2022	2023	2022
Basic:
Weighted average common shares outstanding	54,002,988	53,614,668	53,937,875	53,561,161
Diluted:
Weighted average common shares outstanding - Basic	54,002,988	53,614,668	53,937,875	53,561,161
Common stock equivalents*	—	—	—	—
Denominator for diluted net loss per share	54,002,988	53,614,668	53,937,875	53,561,161

*	No amounts were considered as their effects would be anti-dilutive.

Basic and diluted net loss per share are computed as follows:


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2023		2022		2023		2022
Net loss - basic and diluted	$	(31,479)	$	(4,206)	$	(58,144)	$	(31,955)
Weighted-average common shares outstanding:
Basic and diluted		54,002,988		53,614,668		53,937,875		53,561,161
Net loss per share, basic and diluted:	$	(0.58)	$	(0.08)	$	(1.08)	$	(0.60)

As of June 30, 2023, 8,134,597 stock options and 791,853 restricted stock units were outstanding, which could potentially dilute basic earnings per share in the future, but were not included in the computation of diluted net loss per share because to do so would have been anti-dilutive as a result of the net loss for the period.

As of June 30, 2022, 7,419,027 stock options and 648,450 restricted stock units were outstanding, which could potentially dilute basic earnings per share in the future, but were not included in the computation of diluted net loss per share because to do so would have been anti-dilutive as a result of the net loss for the period.

Stock-Based Compensation - Stock Award Modifications (Details) - Former President and C E O [Member] - USD ($) $ in Thousands	1 Months Ended		3 Months Ended	6 Months Ended
	Feb. 28, 2022	Nov. 30, 2021	Jun. 30, 2022	Jun. 30, 2022
Modified Awards [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period of awards granted		12 months
Share-based Compensation Arrangement Period During Which Continuous Service Must Be Performed For Awards To Be Modified		12 months
Awards that would have vested during the period following the consulting period are deemed to be type 3 modifications		12 months
Term of modified exercise period of awards		18 months
Modified Awards [Member] \| Performance Restricted Stock Units [Member] \| General and Administrative [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total incremental stock compensation expense relating to modifications of Stock Awards			$ 999	$ 2,563
Incremental stock compensation expense relating to modification of stock options			$ 776	$ 1,679
Type 4 modification [Member] \| Performance Restricted Stock Units [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock units, vested	17,333

Restricted Cash - Schedule of Reconciliation of Cash, Cash Equivalents and Restricted Cash (Detail) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022	Jun. 30, 2022	Dec. 31, 2021
Restricted Cash
Cash and cash equivalents	$ 58,249	$ 63,741
Restricted cash, current assets	408	408
Restricted cash, long-term assets	1,500
Total cash, cash equivalents, and restricted cash shown in the Condensed Statements of Cash Flows	$ 60,157	$ 64,149	$ 47,126	$ 13,861

Fair Value Measurements (Tables)

6 Months Ended

Jun. 30, 2023

Fair Value Measurements

Summary of Financial Assets Measured at Fair Value on Recurring Basis

Fair value measurement as of June 30, 2023:


			Quoted prices in		Significant other		Significant
Financial assets			active markets for		observable		unobservable
			identical assets		inputs		inputs
Type of Instrument	Total		(Level 1)		(Level 2)		(Level 3)
Cash and cash equivalents:
Money market funds and checking accounts	$	58,249	$	58,249	$	—	$	—
Available-for-sale marketable securities:
U.S. government agency obligations		9,003		—		9,003		—
Corporate bonds		19,675		—		19,675		—
Municipal bonds		14,817		—		14,817		—
Restricted cash:
Commercial money market account		1,908		1,908		—		—
Total financial assets	$	103,652	$	60,157	$	43,495	$	—

Fair value measurement as of December 31, 2022:


			Quoted prices in		Significant other		Significant
Financial assets			active markets for		observable		unobservable
			identical assets		inputs		inputs
Type of Instrument	Total		(Level 1)		(Level 2)		(Level 3)
Cash and cash equivalents:
Money market funds and checking accounts	$	63,741	$	63,741	$	—	$	—
Available-for-sale marketable securities:
U.S. government agency obligations		8,877		—		8,877		—
Corporate bonds		35,185		—		35,185		—
Commercial paper		26,875		—		26,875		—
Municipal bonds		22,071		—		22,071		—
Restricted cash:
Commercial money market account		408		408		—		—
Total financial assets	$	157,157	$	64,149	$	93,008	$	—

Fair Value Measurements - Additional Information (Detail) - Significant Unobservable Inputs (Level 3) [Member] - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Purchases of financial assets	$ 0	$ 0	$ 0	$ 0
Sales of financial assets	0	0	0	0
Maturities of financial assets	0	0	0	0
Unrealized gains	0	0	0	0
Unrealized losses	0	0	0	0
Transfer of financial assets into or out of level 3 of fair value	$ 0	$ 0	$ 0	$ 0

Prepaid expenses

6 Months Ended

Jun. 30, 2023

Prepaid expenses

Prepaid expenses

8. Prepaid expenses

As of June 30, 2023, prepaid expenses were $14,976, consisting of $12,561 of prepaid R&D clinical costs, $1,400 of prepaid insurance and $1,015 of other prepaid costs. As of December 31, 2022, prepaid expenses were $16,267, consisting of $15,188 of prepaid R&D clinical costs, $543 of prepaid insurance, and $536 of other prepaid costs.

Restricted Cash - Additional Information (Detail) $ in Thousands	Jun. 30, 2023 USD ($)	May 31, 2023 ft²	Dec. 31, 2022 USD ($)
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash, current assets	$ 408		$ 408
Restricted cash, long-term assets	1,500
New Stamford Lease [Member]
Restricted Cash and Cash Equivalents Items [Line Items]
Letters of credit, face amount that can be reduced	500
Restricted cash, long-term assets	1,500
Area of Real Estate Property Subject to Lease \| ft²		26,374
Stamford Lease [Member]
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash, current assets	$ 408		$ 408

Business - Additional Information (Detail) $ in Thousands	1 Months Ended		3 Months Ended				6 Months Ended
Business - Additional Information (Detail) $ in Thousands	Oct. 31, 2020	May 31, 2018	Jun. 30, 2023 USD ($) item	Mar. 31, 2023 USD ($)	Jun. 30, 2022 USD ($)	Mar. 31, 2022 USD ($)	Jun. 30, 2023 USD ($) item	Jun. 30, 2022 USD ($)	Dec. 31, 2022 USD ($)
Nature Of Business [Line Items]
Date of formation							Jul. 02, 2004
Proceeds from equity and debt financing			$ 519,600				$ 519,600
Number of follow-on public offerings \| item			4				4
Payments received in connection with license and supply agreements			$ 279,900				$ 279,900
Unrestricted cash and cash equivalents and marketable securities			101,744				101,744
Accumulated deficit			624,376				624,376		$ 566,232
Net loss			$ (31,479)	$ (26,665)	$ (4,206)	$ (27,749)	(58,144)	$ (31,955)
Net cash used in operating activities							(55,063)	$ (30,028)
Vifor Fresenius Medical Care Renal Pharma Ltd Agreement No 2 [Member]
Nature Of Business [Line Items]
Percentage of net profit sharing		50.00%
CSL Vifor [Member] \| Vifor Fresenius Medical Care Renal Pharma Ltd Agreement No 1 [Member]
Nature Of Business [Line Items]
Percentage of net profit sharing	40.00%
Vifor International Ltd. [Member]
Nature Of Business [Line Items]
Proceeds from the sale of common stock under license agreement with Vifor International							$ 98,000
Vifor Fresenius Medical Care Renal Pharma, Ltd [Member] \| Vifor Fresenius Medical Care Renal Pharma Ltd Agreement No 2 [Member]
Nature Of Business [Line Items]
Percentage of net profit sharing		50.00%
CSL Vifor [Member] \| Vifor Fresenius Medical Care Renal Pharma Ltd Agreement No 1 [Member]
Nature Of Business [Line Items]
Percentage of net profit sharing	60.00%

Basis of Presentation

6 Months Ended

Jun. 30, 2023

Business.

Basis of Presentation

2. Basis of Presentation

The unaudited interim condensed financial statements included herein have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission, or SEC. Accordingly, they do not include all information and disclosures necessary for a presentation of the Company’s financial position, results of operations and cash flows in conformity with generally accepted accounting principles in the United States of America, or GAAP. In the opinion of

management, these unaudited interim financial statements reflect all adjustments, consisting primarily of normal recurring accruals, necessary for a fair presentation of results for the periods presented. The results of operations for interim periods are not necessarily indicative of the results for the full year. Certain information and footnote disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted from this report, as is permitted by SEC rules and regulations; however, the Company believes that the disclosures are adequate to make the information presented not misleading. The condensed balance sheet data as of December 31, 2022 were derived from audited financial statements, but do not include all disclosures required by GAAP. These unaudited interim condensed financial statements should be read in conjunction with the audited financial statements and accompanying notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2022.

Use of Estimates

The preparation of financial statements in conformity with GAAP requires the Company to make estimates and assumptions that affect the reported amounts of assets and liabilities, and disclosure of contingent assets and liabilities, as of the date of the financial statements as well as the reported amounts of revenues and expenses during the reporting period. The more significant estimates include the fair value of marketable securities that are classified as level 2 of the fair value hierarchy, the amount and periods over which certain revenues will be recognized, including licensing and collaborative revenue recognized from non-refundable up-front and milestone payments, related party accounts receivable reserve, as applicable, inventory valuation and related reserves, research and development, or R&D, clinical costs and accrued research projects included in prepaid expenses and accounts payable and accrued expenses, the amount of non-cash compensation costs related to share-based payments to employees and non-employees, the incremental borrowing rate used in lease calculations and the likelihood of realization of deferred tax assets.

The impact from global economic conditions and potential and continuing disruptions to and volatility in the credit and equity markets in the United States and worldwide are highly uncertain and cannot be predicted, including impacts from the COVID-19 pandemic or future public health crises, geopolitical tensions, such as the ongoing military conflict between Russia and Ukraine and related sanctions against Russia, decades-high inflation, rising interest rates, uncertainty and liquidity concerns in the broader financial services industry, such as those caused by certain recent banking failures, and a potential recession in the United States. Estimates and assumptions about future events and their effects cannot be determined with certainty and therefore require the exercise of judgment. As of the date of issuance of these condensed financial statements, the Company is not aware of any specific event or circumstance that would require the Company to update its estimates, assumptions and judgments or revise the reported amounts of assets and liabilities or the disclosure of contingent assets and liabilities. These estimates, however, may change as new events occur and additional information is obtained, and are recognized in the condensed financial statements as soon as they become known.

Actual results could differ materially from the Company’s estimates and assumptions.

Significant Accounting Policies

There have been no material changes to the significant accounting policies previously disclosed in Note 2 to the Financial Statements in the Company’s Annual Report on Form 10-K for the year ended December 31, 2022.

Stock-Based Compensation

6 Months Ended

Jun. 30, 2023

Stock-Based Compensation

Stock-Based Compensation

14. Stock-Based Compensation

2019 Inducement Plan

In October 2019, the Company’s Board of Directors adopted the 2019 Inducement Plan, or the 2019 Plan, which is a non-stockholder approved stock plan adopted pursuant to the “inducement exception” provided under Nasdaq Listing Rule 5635(c)(4), or Rule 5635, for the purpose of awarding (i) non-statutory stock options, (ii) restricted stock awards, (iii) restricted stock unit awards, (iv) other stock awards (collectively, the Inducement Awards) to new employees of the Company, as inducement material to such new employees entering into employment with the Company. In November 2019, the Company filed a Registration Statement on Form S-8 with the SEC covering the offering of up to 300,000 shares of its common stock, par value $0.001, pursuant to the Company’s 2019 Plan. Initial grants of Inducement Awards made to employees vest as to 25% on the first anniversary of the date of grant and the balance ratably over the next 36 months and subsequent grants vest monthly over a period of four years from the grant date.

2014 Equity Incentive Plan

The Company’s 2014 Equity Incentive Plan, or the 2014 Plan, is administered by the Company’s Board of Directors or a duly authorized committee thereof, referred to as the Plan administrator. The 2014 Plan provides for the grant of incentive stock options, non-statutory stock options, restricted stock awards, restricted stock unit awards, stock appreciation rights, performance stock awards and other forms of equity compensation, collectively referred to as Stock Awards. Additionally, the 2014 Plan provides for the grant of performance cash awards. Incentive stock options may be granted only to employees. All other awards may be granted to employees, including officers, non-employee directors, and consultants. No incentive stock options may be granted under the 2014 Plan after the tenth anniversary of the effective date of the 2014 Plan. Stock Awards granted under the 2014 Plan vest at the rate specified by the Plan administrator. Initial grants of Stock Awards made to employees and non-employee consultants generally vest as to 25% on the first anniversary of the date of grant and the balance ratably over the next 36 months and subsequent grants vest monthly over a period of four years from the grant date. Stock options initially granted to members of the Company’s Board of Directors generally vest over a period of three years in equal quarterly installments from the date of the grant, subject to the option holder’s continued service as a director through such date. Subsequent grants to directors that are made automatically at Annual Meetings of Stockholders vest fully on the earlier of the first anniversary of the date of grant and the next Annual Meeting of Stockholders. The Plan administrator determines the term of Stock Awards granted under the 2014 Plan up to a maximum of ten years.

The aggregate number of shares of the Company’s common stock reserved for issuance under the 2014 Plan has automatically increased on January 1 of each year, beginning on January 1, 2015 and will continue to increase on January 1 of each year through and including January 1, 2024, by 3% of the total number of shares of the Company’s capital stock outstanding on December 31 of the preceding calendar year, or a lesser number of shares determined by the Company’s Board of Directors. On January 1, 2023, the aggregate number of shares of common stock that may be issued pursuant to Stock Awards under the 2014 Plan automatically increased from 10,589,103 to 12,203,023. The

maximum number of shares that may be issued pursuant to the exercise of incentive stock options under the 2014 Plan is 30,000,000 shares.

Restricted Stock Units

Pursuant to the Company’s non-employee director compensation policy, an aggregate of 194,172 restricted stock units were granted to non-employee directors on June 1, 2023, the date of the Company’s 2023 Annual Meeting of Stockholders, under the 2014 Plan with a grant date fair value of $3.09 per share. The restricted stock units will vest on the earlier of (i) June 1, 2024 and (ii) immediately prior to the Company’s next Annual Meeting of Stockholders following the grant date, subject to the recipient’s continued service through such date. As a result, the Company recognizes compensation expense associated with these restricted stock units ratably over the one-year vesting period following the grant date. For each of the three and six months ended June 30, 2023, stock compensation expense associated with these awards of $49 was recognized in general and administrative expense, or G&A expense. As of June 30, 2023, 194,172 restricted stock units were outstanding and available to vest and settle in shares of the Company’s common stock.

On March 1, 2023, the Compensation Committee of the Company’s Board of Directors, or the Compensation Committee, approved and granted a total of 407,000 restricted stock units to certain employees under the 2014 Plan with a grant date fair value of $10.06 per share. Vesting of the restricted stock units is contingent on the achievement of certain performance targets, subject to the recipient’s continuous service through each performance target. Recognition of compensation expense associated with these awards begins when, and to the extent, the performance criteria are probable of achievement and the employee has met the service conditions. For each of the three and six months ended June 30, 2023, no stock compensation expense relating to these restricted stock units was recognized. As of June 30, 2023, 407,000 restricted stock units were outstanding and available to vest and settle in shares of the Company’s common stock.

On October 12, 2022, the Compensation Committee approved and granted a total of 7,267 time-based restricted stock units under the 2014 Plan, with a grant date fair value of $9.42 per share, to an executive officer of the Company. The restricted stock unit grant fully vests on August 31, 2023, subject to the recipient’s continued service through such date. For the three and six months ended June 30, 2023, the Company recognized $19 and $38, respectively, of stock compensation expense associated with these awards, all of which was recorded within G&A expense. As of June 30, 2023, 7,267 restricted stock units were outstanding and available to vest and settle in shares of the Company’s common stock.

On June 15, 2022, the Compensation Committee approved and granted a total of 7,500 time-based restricted stock units to the Company’s interim principal financial officer and principal accounting officer, as a result of his assuming the responsibilities of the Company’s former Chief Financial Officer on an interim basis, under the 2014 Plan with a grant date fair value of $7.94 per share. As a result, the Company recognized compensation expense associated with these restricted stock units ratably over the vesting period following the grant date. For each of the three and six months ended June 30, 2022, the Company recognized $5 of stock compensation expense associated with these awards, all of which were recorded within G&A expense. As of June 30, 2023, none of these restricted stock units were outstanding as these restricted stock units vested fully in September 2022.

Pursuant to the Company’s non-employee director compensation policy, an aggregate of 59,380 restricted stock units were granted to non-employee directors on June 2, 2022, the date of the Company’s 2022 Annual Meeting of Stockholders, under the 2014 Plan with a grant date fair value of $8.42 per share. As a result, the Company recognizes compensation expense associated with these restricted stock units ratably over the one-year vesting period following the grant date. For the three and six months ended June 30, 2023, stock compensation expense associated with these awards

of $86 and $209, respectively, was recognized in G&A expense. For each of the three and six months ended June 30, 2022, stock compensation expense of $38 was recognized in G&A expense. As of June 30, 2023, none of these restricted stock units were outstanding as these restricted stock units vested fully on June 2, 2023. Also in June 2022, the Company granted 11,876 fully vested restricted stock units, which were immediately settled in shares of common stock, to the Company’s chairman in consideration of his effort in connection with the Company’s CEO transition in 2021. For each of the three and six months ended June 30, 2022, stock compensation expense of $100 was recognized in G&A expense associated with this award.

On February 25, 2022, the Compensation Committee also approved and granted a total of 243,000 restricted stock units to certain employees under the 2014 Plan with a grant date fair value of $10.46 per share. Vesting of the restricted stock units is contingent on the achievement of certain performance targets related to commercial milestones, subject to the recipient’s continuous service through each performance target. Recognition of compensation expense associated with these awards begins when, and to the extent, the performance criteria are probable of achievement and the employee has met the service conditions. For each of the three and six months ended June 30, 2023 and 2022, no stock compensation expense relating to these restricted stock units was recognized. In June 2022, 29,000 of these restricted stock units were forfeited as a result of the resignation of our former CFO. In December 2022, 214,000 of these restricted stock units were cancelled as the performance targets associated with them were not achieved. As of June 30, 2023, none of these restricted stock units were outstanding as the remaining restricted stock units were cancelled in 2022.

Additionally, on February 25, 2022, the Compensation Committee also approved and granted a total of 145,170 time-based restricted stock units to certain employees under the 2014 Plan with a grant date fair value of $10.46 per share. The restricted stock units vest in three equal installments annually from the date of the grant. As a result, the Company recognizes compensation expense associated with these restricted stock units ratably over the three-year vesting period following the grant date. In April 2023, 3,585 of these restricted stock units were forfeited. In February 2023, 42,920 of these restricted stock units vested and were settled in shares of the Company’s common stock in satisfaction of the first year of vesting. For the three and six months ended June 30, 2023, the Company recognized $85 and $199, respectively, of stock compensation expense associated with these awards, with $17 recorded in R&D expense and $68 recorded in G&A expense for the three months ended June 30, 2023, and $64 recorded in R&D expense and $135 recorded in G&A expense for the six months ended June 30, 2023. For the three and six months ended June 30, 2022, the Company recognized $108 and $158, respectively, of stock compensation expense associated with these awards, with $47 recorded in R&D expense and $61 recorded in G&A expense for the three months ended June 30, 2022, and $65 recorded in R&D expense and $93 recorded in G&A expense for the six months ended June 30, 2022. During the three months ended June 30, 2022, 20,000 of these restricted stock units were forfeited as a result of the resignation of the Company’s former CFO in June 2022. As of June 30, 2023, 78,665 restricted stock units were outstanding and available to vest and settle in shares of the Company’s common stock.

On December 17, 2021, the Compensation Committee approved and granted a total of 63,573 time-based restricted stock units to certain employees under the 2014 Plan with a grant date fair value of $12.45 per share. The restricted stock units vested in two equal installments on December 15, 2022 and June 15, 2023. As a result, the Company recognized compensation expense associated with these restricted stock units ratably over the 18-month vesting period following the grant date. On June 15, 2023, the remaining 26,199 of these restricted stock units fully vested and were settled in shares of the Company’s common stock. For the three and six months ended June 30, 2023, the Company recognized $91 and $199, respectively, of stock compensation expense associated with these awards, with $44 recorded in R&D expense and $47 recorded in G&A expense for the three months ended June 30, 2023, and $96 recorded in R&D expense and $103 recorded in G&A expense for the six months ended June 30, 2023. In June 2022, 11,170 of these restricted stock units were forfeited as a result of the resignation of the Company’s former CFO. For the three and six months ended June 30, 2022, the Company recognized $82 and $213, respectively, of stock compensation expense associated with these awards,

with $52 recorded in R&D expense and $30 recorded in G&A expense for the three months ended June 30, 2022, and $104 recorded in R&D expense and $109 recorded in G&A expense for the six months ended June 30, 2022. As of June 30, 2023, none of these restricted stock units were outstanding as the remaining restricted stock units fully vested in June 2023.

On October 29, 2021, the Compensation Committee also approved and granted 147,942 time-based restricted stock units in connection with the appointment of the Company’s new CEO under the 2014 Plan with a grant date fair value of $16.83 per share. The first tranche of 142,000 restricted stock units vested 25% on the first anniversary of the date of grant and the balance vests quarterly over the next 36 months. As a result, 35,500 of these restricted stock units vested and were settled in shares of the Company’s common stock in October 2022. The second tranche of 5,942 restricted stock units fully vested on March 31, 2022. As a result, the Company recognizes compensation expense associated with these two restricted stock unit tranches ratably over their respective vesting periods following the grant date. In April 2023 and January 2023, 8,875 of these restricted stock units vested each period and were settled in shares of the Company’s common stock in satisfaction of the quarterly periods of vesting. For the three and six months ended June 30, 2023, stock compensation expense associated with these awards of $149 and $296, respectively, was recognized in G&A expense. For the three and six months ended June 30, 2022, stock compensation expense associated with these awards of $149 and $355, respectively, was recognized in G&A expense. As of June 30, 2023, 88,750 restricted stock units were outstanding and available to vest and settle in shares of the Company’s common stock.

Pursuant to the Company’s non-employee director compensation policy, an aggregate of 43,200 restricted stock units were granted to non-employee directors on June 3, 2021, the date of the Company’s 2021 Annual Meeting of Stockholders, under the 2014 Plan with a grant date fair value of $13.06 per share. The restricted stock units vested on June 3, 2022. As a result, the Company recognized compensation expense associated with these restricted stock units ratably over the one-year vesting period following the grant date. For the three and six months ended June 30, 2022, stock compensation expense associated with these awards of $100 and $239, respectively, was recognized in G&A expense for these restricted stock units. As of June 30, 2023, none of these restricted stock units were outstanding as the remaining restricted stock units fully vested in June 2022.

On March 30, 2021, the Compensation Committee approved and granted a total of 176,000 restricted stock units to certain employees under the 2014 Plan with a grant date fair value of $20.59 per share. Vesting of the restricted stock units was contingent on the achievement of certain performance targets related to clinical and regulatory milestones, subject to the recipient’s continuous service through each performance target. Recognition of compensation expense associated with these awards begins when, and to the extent, the performance criteria is probable of achievement and the employee has met the service conditions. In March 2022, 93,999 restricted stock units were forfeited as a result of not achieving certain defined performance targets of the awards. In February 2022, performance targets relating to 37,999 restricted stock units had been achieved and thus restricted stock units vested and the awards were settled in shares of common stock. For each of the three and six months ended June 30, 2023, there was no stock compensation expense recognized as all of these restricted stock units either vested or were forfeited prior to these periods. For the six months ended June 30, 2022, the Company recognized $729 of stock compensation expense associated with these awards in G&A expense. G&A amounts recorded for the six months ended June 30, 2022 included $303 of stock compensation expense relating to the modification of certain of these restricted stock units on November 1, 2021 (see Stock Award Modifications below). As of June 30, 2023, none of these restricted stock units were outstanding as the remaining restricted stock units either fully vested or were forfeited in prior periods.

Additionally on March 30, 2021, the Compensation Committee also approved and granted a total of 100,000 time-based restricted stock units to certain employees under the 2014 Plan with a grant date fair value of $20.59 per share. The restricted stock units vest in three equal installments annually from the date of the grant. As a result, the Company recognizes compensation expense associated with these restricted stock units ratably over the three-year vesting period

following the grant date. In March 2023, 15,999 of these restricted stock units vested and were settled in shares of the Company’s common stock in satisfaction of the second year of vesting. In June 2022, 17,333 of these restricted stock units vested and were settled in shares of the Company’s common stock in accordance with the acceleration of vesting provisions relating to the modification of certain of these restricted stock units on November 1, 2021. In June 2022, 17,333 restricted stock units were forfeited as a result of the completion of the consulting agreement in relation to the modification of certain of these restricted stock units on November 1, 2021 (see Stock Award Modifications below). In March 2022, 33,336 of these restricted stock units vested and were settled in shares of the Company’s common stock in satisfaction of the first year of vesting. For the three and six months ended June 30, 2023, the Company recognized $82 and $163, respectively, of stock compensation expense associated with these awards, with $55 recorded in R&D expense and $27 in G&A expense for the three months ended June 30, 2023, and $109 recorded in R&D expense and $54 in G&A expense for the six months ended June 30, 2023. For the three and six months ended June 30, 2022, the Company recognized $196 and $480, respectively, of stock compensation expense associated with these awards, with $55 recorded in R&D expense and $141 in G&A expense for the three months ended June 30, 2022, and $109 recorded in R&D expense and $371 in G&A expense for the six months ended June 30, 2022. G&A amounts recorded for the three and six months ended June 30, 2022 included $114 and $317, respectively, of stock compensation expense relating to the modification of certain of these restricted stock units on November 1, 2021 (see Stock Award Modifications below). As of June 30, 2023, 15,999 restricted stock units were outstanding and available to vest and settle in shares of the Company’s common stock.

In February 2020, the Compensation Committee also approved and granted a total of 98,000 time-based restricted stock units to certain employees under the 2014 Plan with a grant date fair value of $16.36 per share. The restricted stock units vested in three equal installments annually from the date of the grant. As a result, the Company recognized compensation expense associated with these restricted stock units ratably over the three-year vesting period following the grant date. In February 2023, 15,999 of these restricted stock units vested and were settled in shares of the Company’s common stock in satisfaction of the third year of vesting. In February 2022, 32,666 of these restricted stock units vested and were settled in shares of the Company’s common stock in satisfaction of the second year of vesting. For the six months ended June 30, 2023, the Company recognized $39 of stock compensation expense associated with these awards, with $26 recorded in R&D expense and $13 in G&A expense. There was no associated stock compensation expense for the three months ended June 30, 2023 as these restricted stock units were fully vested in the prior period. For the three and six months ended June 30, 2022, the Company recognized $175 and $394, respectively, of stock compensation expense associated with these awards, with $44 recorded in R&D expense and $131 in G&A expense for the three months ended June 30, 2022, and $87 recorded in R&D expense and $307 in G&A expense for the six months ended June 30, 2022. G&A amounts recorded for the three and six months ended June 30, 2022 included $109 and $264, respectively, of stock compensation expense relating to the modification of certain of these restricted stock units on November 1, 2021 (see Stock Award Modifications below). As of June 30, 2023, none of these restricted stock units were outstanding as the remaining restricted stock units were fully vested in February 2023.

A summary of restricted stock unit activity related to employees and non-employee members of the Company’s Board of Directors as of and for the six months ended June 30, 2023 is presented below:


		Weighted
	Number of	Average Grant
	Units	Date Fair Value
Outstanding, December 31, 2022	372,513	$	13.20
Awarded	601,172		7.81
Vested and released	(178,247)		12.15
Forfeited	(3,585)		10.46
Outstanding, June 30, 2023	791,853	$	9.36
Restricted stock units exercisable (vested and deferred), June 30, 2023	—

Stock Options

Under the 2014 Plan, the Company granted 349,767 and 324,981 stock options during the three months ended June 30, 2023 and 2022, respectively, and 1,798,921 and 1,302,419 stock options during the six months ended June 30, 2023 and 2022, respectively. No stock options were granted under the 2019 Inducement Plan during the three and six months ended June 30, 2023 and 2022. The fair values of stock options granted during the three and six months ended June 30, 2023 and 2022 were estimated as of the dates of grant using the Black-Scholes option pricing model with the following assumptions:


	Three Months Ended		Six Months Ended
	June 30,		June 30,
	2023	2022	2023	2022
Risk-free interest rate	3.38% - 3.89%	2.83% - 3.54%	3.38% - 4.22%	1.70% - 3.54%
Expected volatility	80.3% - 81.3%	77.8% - 81.5%	76.3% - 81.3%	77.8% - 81.9%
Expected dividend yield	0%	0%	0%	0%
Expected life of employee and Board options (in years)	6.25	6.25	6.25	6.25

The weighted-average grant date fair value per share of options granted to employees and non-employee members of the Company’s Board of Directors for their Board service during the three months ended June 30, 2023 and 2022 was $2.43 and $6.30, respectively, and during the six months ended June 30, 2023 and 2022 was $6.18 and $7.23, respectively. No options were granted to non-employee consultants during the three and six months ended June 30, 2023 and 2022.

During the three and six months ended June 30, 2023 and 2022, the Company recognized compensation expense relating to stock options as follows:


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2023		2022		2023		2022
Research and development	$	1,447	$	1,744	$	2,927	$	3,661
General and administrative		1,434		1,958		2,675		3,988
Total stock option expense	$	2,881	$	3,702	$	5,602	$	7,649

The following were excluded from the table above as they are not related to stock options: compensation expense for (i) the vesting of certain employees’ restricted stock units for $116 in R&D expense and $310 in G&A expense for the three months ended June 30, 2023, and $295 in R&D expense and $639 in G&A expense for the six months ended June 30, 2023; (ii) the vesting of certain employees’ restricted stock units for $198 in R&D expense and $517 in G&A expense for the three months ended June 30, 2022, and $365 in R&D expense and $1,969 in G&A expense for the six months ended June 30, 2022; (iii) compensation expense relating to the Board of Directors’ restricted stock units for $135 and $258 in G&A expense for the three and six months ended June 30, 2023, respectively; and (iv) compensation expense relating to the Board of Directors’ restricted stock units for $238 and $377 in G&A expense for the three and six months ended June 30, 2022, respectively.

A summary of stock option award activity related to employees, non-employee members of the Company’s Board of Directors and non-employee consultants as of and for the six months ended June 30, 2023 is presented below:


		Weighted
	Number of	Average Exercise
	Shares	Price
Outstanding, December 31, 2022	7,689,449	$	14.35
Granted	1,798,921		8.76
Exercised	(93,218)		6.00
Forfeited	(117,629)		11.27
Expired	(1,142,926)		14.35
Outstanding, June 30, 2023	8,134,597	$	13.25
Options exercisable, June 30, 2023	4,388,343

The Company does not expect to realize any tax benefits from its stock option activity or the recognition of stock-based compensation expense because the Company currently has net operating losses and has a full valuation allowance against its deferred tax assets. Accordingly, no amounts related to excess tax benefits have been reported in cash flows from operations for the six months ended June 30, 2023 and 2022.

Stock Award Modifications

In November 2021, the Company and the former President and CEO mutually agreed to a transition from CEO to a consulting role through June 30, 2022, if not terminated earlier per the terms of the consulting agreement. As a result, the Company modified the terms of its former CEO’s outstanding Stock Awards to (1) automatically vest any unvested stock options or time-based restricted stock units that would have vested in the twelve month period following the end of the consulting period if continuous service is achieved with the Company during such twelve-month period; (2) extend the period during which the vested stock options may be exercised through the earlier of (i) eighteen months following the separation date (November 8, 2021); or (ii) the original expiration date applicable to each of the stock options, unless terminated earlier in accordance with the 2014 Plan, if continuous service is achieved with the Company; and (3) extend the period in which performance-based vesting milestones for restricted stock units may be achieved through March 31, 2022, if continuous service is achieved with the Company. The consulting agreement ended on June 30, 2022.

The Company determined that vested Stock Awards which had modifications due to the extension of the exercise period were Type 1 modifications pursuant to Financial Accounting Standards Board Accounting Standards Codification 718, or ASC 718, because those Stock Awards would have vested before and after the modification. Acceleration of vesting for the Stock Awards that would have vested in the twelve-month period following the consulting term was determined to be a Type 3 modification requiring stock compensation expense pursuant to ASC 718 because absent the modification terms, those Stock Awards would have been forfeited as of the last day that the former CEO provided

continuous service as a consultant. In addition, Type 4 performance-based restricted stock units were not considered probable of achieving performance targets on the modification date, but the vesting targets were achieved with respect to 17,333 performance-based restricted stock units in February 2022, which resulted in additional stock compensation expense being recorded during the six months ended June 30, 2022.

During the three and six months ended June 30, 2022, total incremental stock compensation expense relating to modifications of stock options, time-based and performance-based restricted stock units of the former CEO was $999 and $2,563, respectively, which was included in G&A expense for the three and six months ended June 30, 2022, respectively. Of this total amount, $776 and $1,679 were included in G&A expense in the stock option compensation expense table above for the three and six months ended June 30, 2022, respectively.

Commitments and Contingencies (Tables)

6 Months Ended

Jun. 30, 2023

Commitments and Contingencies

Schedule of Other Information related to Stamford Lease and lease amendment


	Three Months Ended June 30,						Six Months Ended June 30,
	2023			2022			2023			2022
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash outflows relating to operating leases	$	496		$	487		$	990		$	972
ROU assets obtained in exchange for new operating lease liabilities	$	—		$	—		$	—		$	—
Remaining lease term - operating leases (years)		0.5			1.5			0.5			1.5
Discount rate - operating leases		7.0	%		7.0	%		7.0	%		7.0	%

Schedule of Future Minimum Lease Payments under Non-cancellable Operating Leases, Reconciliation of Undiscounted Cash Flows to the Operating Lease Liabilities


Year Ending December 31,
2023 (Excluding the six months ended June 30, 2023)	$	1,002
Total future minimum lease payments, undiscounted		1,002
Less imputed interest		(20)
Total	$	982

Operating lease liabilities reported as of June 30, 2023:
Operating lease liabilities - current	$	982
Operating lease liabilities - non-current		—
Total	$	982

Commitments and Contingencies - Schedule of Other Information related to Stamford Lease and New Stamford Lease (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Commitments and Contingencies
Operating cash outflows relating to operating leases	$ 496	$ 487	$ 990	$ 972
ROU assets obtained in exchange for new operating lease liabilities
Remaining lease term - operating leases (years)	6 months	1 year 6 months	6 months	1 year 6 months
Discount rate - operating leases	7.00%	7.00%	7.00%	7.00%

Revenue Recognition

6 Months Ended

Jun. 30, 2023

Revenue Recognition

Revenue Recognition

12. Revenue Recognition

The Company primarily recognizes revenue under its license and collaboration agreements from (1) collaborative revenue from its share of the profit generated by KORSUVA injection sales in the United States; (2) commercial supply revenue from the Company’s sales of commercial product to CSL Vifor, which is subsequently sold to wholesalers; (3) royalty revenue from net sales of Kapruvia in Europe; and (4) sales-based or regulatory milestone payments, which could be earned in the future in accordance with certain licensing agreements. As of June 30, 2023, the Company has not earned any sales-based milestones under its collaboration agreements.

As of June 30, 2023, the Company had license and collaboration agreements with CSL Vifor, Maruishi and CKDP. The following table provides amounts included in the Company’s Condensed Statements of Comprehensive Loss as revenue for the three and six months ended June 30, 2023 and 2022, respectively:


	Three Months Ended June 30,				Six Months Ended June 30,
	2023		2022		2023		2022
Collaborative revenue
CSL Vifor (KORSUVA injection profit sharing)	$	5,410	$	8,003	$	8,160	$	8,003
Total collaborative revenue	$	5,410	$	8,003	$	8,160	$	8,003
Commercial supply revenue
CSL Vifor* (KORSUVA injection)	$	1,400	$	—	$	4,591	$	4,790
Total commercial supply revenue	$	1,400	$	—	$	4,591	$	4,790
Royalty revenue
CSL Vifor (Kapruvia ex U.S.)	$	123	$	—	$	248	$	—
Total royalty revenue	$	123	$	—	$	248	$	—
License and milestone fees
Vifor Fresenius Medical Care Renal Pharma Ltd.	$	—	$	15,000	$	—	$	15,000
Total milestone and fees	$	—	$	15,000	$	—	$	15,000
Clinical compound revenue
Maruishi	$	—	$	—	$	99	$	—
Total clinical compound revenue	$	—	$	—	$	99	$	—

_____________________________

* Includes amounts earned from Vifor International prior to Vifor International’s assignment of its rights and obligations to Vifor Fresenius Medical Care Renal Pharma Ltd. in May 2022.

Collaborative revenue

Beginning in April 2022, the Company began recording its share of the profit generated by KORSUVA injection sales by CSL Vifor to third parties in the United States. Under the license agreements with CSL Vifor, KORSUVA injection net sales are calculated by CSL Vifor which are net of discounts, rebates, and allowances. These amounts include the use of estimates and judgments, which could be adjusted based on actual results in the future. The Company records its share of the net profits from the sales of KORSUVA injection in the United States on a net basis (since the Company is not the primary obligor and does not retain inventory risk) and presents the revenue earned each period as collaborative revenue. During the three and six months ended June 30, 2023, the Company recorded $5,410 and $8,160, respectively, as collaborative revenue for its profit-share from the sales of KORSUVA injection in the United States. During each of the three and six months ended June 30, 2022, the Company recorded $8,003 as collaborative revenue for its profit-share from the sales of KORSUVA injection in the United States.

Commercial supply revenue

Under the Vifor International Supply Agreement, the Company’s only performance obligation is the delivery of KORSUVA injection to CSL Vifor in accordance with the receipt of purchase orders. Revenue from the sale of commercial supply product to CSL Vifor is recognized as delivery of the product occurs. The Company had commercial supply revenue of $1,400 and $4,591 for the three and six months ended June 30, 2023, respectively, with associated

COGS of $1,418 and $4,008, respectively. The Company had commercial supply revenue of $4,790 for the six months ended June 30, 2022, of which $2,295 was recognized in January 2022 with no associated COGS since these inventory costs were incurred prior to regulatory approval on August 23, 2021, and $2,495 was recognized in March 2022 with associated COGS of $2,081 since these inventory costs were capitalized as inventory subsequent to regulatory approval. There was no commercial supply revenue for the three months ended June 30, 2022.

Royalty revenue

Royalty revenue includes amounts related to the Company’s royalties earned from CSL Vifor on the net sales of Kapruvia in Europe, based on the amount of net sales in a licensed territory during a calendar year. Sales-based royalty payments related to a license of IP are recognized as revenue when the respective sales occur, and the net sales tier is achieved. During the three and six months ended June 30, 2023, the Company recorded $123 and $248, respectively, as royalty revenue based on net sales of Kapruvia. There was no royalty revenue for the three and six months ended June 30, 2022.

License and milestone fees revenue

Under Vifor Agreement No. 2, the Company’s performance obligations of granting a license to allow Vifor Fresenius Medical Care Renal Pharma Ltd. to commercialize difelikefalin injection worldwide, except in the United States, Japan and South Korea, which occurred at inception of the contract in May 2018, and performing R&D services by the Company to obtain sufficient clinical data which were shared with Vifor Fresenius Medical Care Renal Pharma Ltd. to allow them to receive regulatory approval to sell difelikefalin in the licensed territory, were not distinct, and were accounted for as a single performance obligation during the period the that the R&D services were rendered (see Note 11, Collaboration and Licensing Agreements).

Revenue related to achievement of milestone events is recognized when the Company has determined that it is probable that a milestone event will be achieved and there will not be a significant reversal of revenue in future periods. Upon probability of achievement of a milestone event, the most likely amount of variable consideration is included in the transaction price. Subsequent changes to the transaction price, after contract initiation, are allocated to the performance obligations in the contract on the same basis as at contract inception. Revenue for variable consideration is recognized in the same manner (point in time or over time) as for the performance obligations to which the payment amounts were allocated.

As a result of the European Commission’s regulatory approval of Kapruvia in April 2022, the Company achieved a $15,000 regulatory milestone payment from Vifor Fresenius Medical Care Renal Pharma Ltd. under Vifor Agreement No. 2, which was recorded as license and milestone fees revenue for each of the three and six months ended June 30, 2022. This regulatory milestone payment was considered variable consideration due to the uncertainty of occurrence of this event as specified at inception of the agreement. Therefore, this potential regulatory milestone payment was not included in the transaction price at the inception of the agreement.

Clinical compound revenue

The Company’s only performance obligation under the supply agreement with Maruishi is to deliver clinical compound to Maruishi in accordance with the receipt of purchase orders. During the six months ended June 30, 2023, the Company recognized clinical compound revenue of $99 from the sale of clinical compound to Maruishi. There were no sales of clinical compound during the three months ended June 30, 2023, and each of the three and six months ended June 30, 2022.

Contract balances

As of June 30, 2023 and December 31, 2022, respectively, the Company recorded accounts receivable, net – related party of $10,124 and $3,260 which primarily related to its profit-sharing revenue from sales of KORSUVA injection in the United States by CSL Vifor, its commercial supply of KORSUVA injection to CSL Vifor, and royalty revenue from CSL Vifor relating to sales of Kapruvia outside of the United States. There were no other contract assets or contract liabilities related to the CSL Vifor, Maruishi and CKDP agreements as of June 30, 2023 and December 31, 2022.

The Company routinely assesses the creditworthiness of its license and collaboration partners. The Company has not experienced any losses related to receivables from its license and collaboration partners as of June 30, 2023 and December 31, 2022.

- Definition

The entire disclosure of revenue from contract with customer to transfer good or service and to transfer nonfinancial asset. Includes, but is not limited to, disaggregation of revenue, credit loss recognized from contract with customer, judgment and change in judgment related to contract with customer, and asset recognized from cost incurred to obtain or fulfill contract with customer. Excludes insurance and lease contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-URI https://asc.fasb.org/topic&trid=49130388

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 10
-URI https://asc.fasb.org/extlink&oid=126920106&loc=SL49130551-203045

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (b)(2)
-URI https://asc.fasb.org/extlink&oid=126920106&loc=SL49130556-203045

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126920106&loc=SL49130554-203045

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 9
-URI https://asc.fasb.org/extlink&oid=126920106&loc=SL49130550-203045

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (e)
-URI https://asc.fasb.org/extlink&oid=126920106&loc=SL49130554-203045

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126920106&loc=SL49130554-203045

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (d)
-URI https://asc.fasb.org/extlink&oid=126920106&loc=SL49130554-203045

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 15
-URI https://asc.fasb.org/extlink&oid=126920106&loc=SL49130558-203045

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
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-Subparagraph (c)
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+ Details

Available-for-Sale Marketable Securities (Tables)

6 Months Ended

Jun. 30, 2023

Available-for-Sale Marketable Securities

Summary of Available-for-Sale Marketable Securities by Major Type of Security

As of June 30, 2023


			Gross Unrealized				Estimated Fair
Type of Security	Amortized Cost		Gains		Losses		Value
U.S. government agency obligations	$	9,500	$	—	$	(497)	$	9,003
Corporate bonds		19,859		—		(184)		19,675
Municipal bonds		14,866		—		(49)		14,817
Total available-for-sale marketable securities	$	44,225	$	—	$	(730)	$	43,495

As of December 31, 2022


			Gross Unrealized				Estimated Fair
Type of Security	Amortized Cost		Gains		Losses		Value
U.S. government agency obligations	$	9,500	$	—	$	(623)	$	8,877
Corporate bonds		35,828		—		(643)		35,185
Commercial paper		26,879		2		(6)		26,875
Municipal bonds		22,473		—		(402)		22,071
Total available-for-sale marketable securities	$	94,680	$	2	$	(1,674)	$	93,008

Schedule of Fair Values and Continuous Unrealized Loss Positions of Available-for-Sale Marketable Securities

As of June 30, 2023


	Less than 12 Months				12 Months or Greater				Total
			Gross				Gross				Gross
	Fair		Unrealized		Fair		Unrealized		Fair		Unrealized
	Value		Losses		Value		Losses		Value		Losses
U.S. government agency obligations	$	—	$	—	$	9,003	$	(497)	$	9,003	$	(497)
Corporate bonds		—		—		19,675		(184)		19,675		(184)
Municipal bonds		—		—		7,702		(49)		7,702		(49)
Total	$	—	$	—	$	36,380	$	(730)	$	36,380	$	(730)

As of December 31, 2022


	Less than 12 Months				12 Months or Greater				Total
			Gross				Gross				Gross
	Fair		Unrealized		Fair		Unrealized		Fair		Unrealized
	Value		Losses		Value		Losses		Value		Losses
U.S. government agency obligations	$	—	$	—	$	8,877	$	(623)	$	8,877	$	(623)
Corporate bonds		1,470		(26)		33,715		(617)		35,185		(643)
Commercial paper		15,906		(6)		—		—		15,906		(6)
Municipal bonds		982		(16)		19,589		(386)		20,571		(402)
Total	$	18,358	$	(48)	$	62,181	$	(1,626)	$	80,539	$	(1,674)

Schedule of Amortized Cost and Fair Values of Marketable Debt Securities by Contractual Maturity


	As of June 30, 2023				As of December 31, 2022
Contractual maturity	Amortized Cost		Fair Value		Amortized Cost		Fair Value
Less than one year	$	36,725	$	36,442	$	82,678	$	81,658
One year to two years		7,500		7,053		12,002		11,350
Total	$	44,225	$	43,495	$	94,680	$	93,008

CONDENSED STATEMENTS OF COMPREHENSIVE LOSS (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
CONDENSED STATEMENTS OF COMPREHENSIVE LOSS
Other comprehensive income (loss) tax	$ 0	$ 0	$ 0	$ 0

- Definition

Amount of tax expense (benefit) allocated to other comprehensive income (loss).

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+ Details

Basis of Presentation (Policies)	6 Months Ended
Basis of Presentation (Policies)	Jun. 30, 2023
Business.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with GAAP requires the Company to make estimates and assumptions that affect the reported amounts of assets and liabilities, and disclosure of contingent assets and liabilities, as of the date of the financial statements as well as the reported amounts of revenues and expenses during the reporting period. The more significant estimates include the fair value of marketable securities that are classified as level 2 of the fair value hierarchy, the amount and periods over which certain revenues will be recognized, including licensing and collaborative revenue recognized from non-refundable up-front and milestone payments, related party accounts receivable reserve, as applicable, inventory valuation and related reserves, research and development, or R&D, clinical costs and accrued research projects included in prepaid expenses and accounts payable and accrued expenses, the amount of non-cash compensation costs related to share-based payments to employees and non-employees, the incremental borrowing rate used in lease calculations and the likelihood of realization of deferred tax assets. The impact from global economic conditions and potential and continuing disruptions to and volatility in the credit and equity markets in the United States and worldwide are highly uncertain and cannot be predicted, including impacts from the COVID-19 pandemic or future public health crises, geopolitical tensions, such as the ongoing military conflict between Russia and Ukraine and related sanctions against Russia, decades-high inflation, rising interest rates, uncertainty and liquidity concerns in the broader financial services industry, such as those caused by certain recent banking failures, and a potential recession in the United States. Estimates and assumptions about future events and their effects cannot be determined with certainty and therefore require the exercise of judgment. As of the date of issuance of these condensed financial statements, the Company is not aware of any specific event or circumstance that would require the Company to update its estimates, assumptions and judgments or revise the reported amounts of assets and liabilities or the disclosure of contingent assets and liabilities. These estimates, however, may change as new events occur and additional information is obtained, and are recognized in the condensed financial statements as soon as they become known. Actual results could differ materially from the Company’s estimates and assumptions.
Significant Accounting Policies	Significant Accounting Policies There have been no material changes to the significant accounting policies previously disclosed in Note 2 to the Financial Statements in the Company’s Annual Report on Form 10-K for the year ended December 31, 2022.

Document and Entity Information - shares	6 Months Ended
Document and Entity Information - shares	Jun. 30, 2023	Aug. 03, 2023
Document And Entity Information [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2023
Document Transition Report	false
Entity File Number	001-36279
Entity Registrant Name	CARA THERAPEUTICS, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	75-3175693
Entity Address, Address Line One	4 Stamford Plaza
Entity Address, Address Line Two	107 Elm Street
Entity Address, Address Line Three	9th Floor
Entity Address, City or Town	Stamford
Entity Address, State or Province	CT
Entity Address, Postal Zip Code	06902
City Area Code	203
Local Phone Number	406-3700
Title of 12(b) Security	Common Stock, par value $0.001 per share
Trading Symbol	CARA
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		54,077,681
Entity Central Index Key	0001346830
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	Q2
Amendment Flag	false

CONDENSED BALANCE SHEETS (Parenthetical) - $ / shares	Jun. 30, 2023	Dec. 31, 2022
CONDENSED BALANCE SHEETS
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	54,068,806	53,797,341
Common stock, shares outstanding	54,068,806	53,797,341

Net Loss Per Share (Tables)

6 Months Ended

Jun. 30, 2023

Net Loss Per Share

Computation of Denominators Used in Net Loss per Share

The denominators used in the net loss per share computations are as follows:


	Three Months Ended		Six Months Ended
	June 30,		June 30,
	2023	2022	2023	2022
Basic:
Weighted average common shares outstanding	54,002,988	53,614,668	53,937,875	53,561,161
Diluted:
Weighted average common shares outstanding - Basic	54,002,988	53,614,668	53,937,875	53,561,161
Common stock equivalents*	—	—	—	—
Denominator for diluted net loss per share	54,002,988	53,614,668	53,937,875	53,561,161

*	No amounts were considered as their effects would be anti-dilutive.

Computation of Basic and Diluted Net Loss per Share

Basic and diluted net loss per share are computed as follows:


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2023		2022		2023		2022
Net loss - basic and diluted	$	(31,479)	$	(4,206)	$	(58,144)	$	(31,955)
Weighted-average common shares outstanding:
Basic and diluted		54,002,988		53,614,668		53,937,875		53,561,161
Net loss per share, basic and diluted:	$	(0.58)	$	(0.08)	$	(1.08)	$	(0.60)

Accounts Payable and Accrued Expenses - Schedule of Accounts Payable and Accrued Expenses (Detail) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Accounts Payable and Accrued Expenses
Accounts payable	$ 12,122	$ 9,604
Accrued research projects	6,416	5,200
Accrued compensation and benefits	4,196	5,219
Accrued professional fees and other	1,741	1,517
Total	$ 24,475	$ 21,540

Net Loss Per Share - Computation of Denominators Used in Net Loss per Share (Detail) - shares	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Basic:
Weighted average common shares outstanding - Basic	54,002,988	53,614,668	53,937,875	53,561,161
Diluted:
Weighted average common shares outstanding - Basic	54,002,988	53,614,668	53,937,875	53,561,161
Common stock equivalents			0
Denominator for diluted net loss per share	54,002,988	53,614,668	53,937,875	53,561,161

Stockholders' Equity

6 Months Ended

Jun. 30, 2023

Stockholders' Equity

Stockholders' Equity

10. Stockholders’ Equity

In June 2023, as a result of completion of the final vesting period for restricted stock units granted in December 2021, an aggregate of 26,199 time-based restricted stock units vested and were settled in shares of the Company’s common stock (see Note 14, Stock-Based Compensation).

In June 2023, as a result of the completion of the one-year vesting period, an aggregate of 59,380 restricted stock units of members of the Board of Directors vested and were settled in shares of the Company’s common stock (see Note 14, Stock-Based Compensation).

In April 2023, as a result of completion of the quarterly vesting period for restricted stock units granted in October 2021, an aggregate of 8,875 time-based restricted stock units vested and were settled in shares of the Company’s common stock (see Note 14, Stock-Based Compensation).

In March 2023, as a result of the completion of the second year of the three-year vesting period for restricted stock units granted in March 2021, an aggregate of 15,999 time-based restricted stock units vested and were settled in shares of the Company’s common stock (see Note 14, Stock-Based Compensation).

In February 2023, as a result of the completion of the first year of the three-year vesting period for restricted stock units granted in February 2022, an aggregate of 42,920 time-based restricted stock units vested and were settled in shares of the Company’s common stock (see Note 14, Stock-Based Compensation).

Also in February 2023, as a result of the completion of the third year of the three-year vesting period for restricted stock units granted in February 2020, an aggregate of 15,999 time-based restricted stock units vested and were settled in shares of the Company’s common stock (see Note 14, Stock-Based Compensation).

In January 2023, as a result of completion of the quarterly vesting period for restricted stock units granted in October 2021, an aggregate 8,875 time-based restricted stock units vested and were settled in shares of the Company’s common stock (see Note 14, Stock-Based Compensation).

In June 2022, as a result of the accelerated vesting of restricted stock units associated with the former Chief Executive Officer’s, or CEO’s, modification of equity awards, an aggregate of 33,999 restricted stock units vested and were settled in shares of the Company’s common stock (see Note 14, Stock-Based Compensation).

In June 2022, as a result of the completion of the one-year vesting period, an aggregate of 43,200 restricted stock units of members of the Board of Directors vested and were settled in shares of the Company’s common stock. Also in June 2022, the Company granted 11,876 fully vested restricted stock units, which were immediately settled in shares of the Company’s common stock, to the Company’s chairman in consideration of his effort in connection with the Company’s CEO transition in 2021 (see Note 14, Stock-Based Compensation).

In March 2022, as a result of the achievement of certain performance targets, an aggregate of 37,999 performance-based restricted stock units of certain employees vested and were settled in shares of the Company’s common stock (see Note 14, Stock-Based Compensation).

In March 2022, as a result of the completion of the first year of the three-year vesting period for restricted stock units granted in March 2021 and the full vesting of the second tranche of restricted stock units granted to the new Chief Executive Officer in October 2021, an aggregate of 39,278 time-based restricted stock units vested and were settled in shares of the Company’s common stock (see Note 14, Stock-Based Compensation).

In March 2022, the Company filed a universal shelf registration statement, or the Shelf Registration Statement, which provides for aggregate offerings of up to $300,000 of common stock, preferred stock, debt securities, warrants or any combination thereof. The Shelf Registration Statement was declared effective on May 11, 2022. The securities registered under the Shelf Registration Statement include $154,525 of unsold securities that had been registered under

the Company’s previous Registration Statement on Form S-3 (File No. 333-230333) that was declared effective on April 4, 2019.

Also in March 2022, the Company entered into an open market sales agreement, or the Sales Agreement, with Jefferies LLC, as sales agent, pursuant to which it may, from time to time, issue and sell common stock with an aggregate value of up to $80,000 in an at-the-market offering. Jefferies is acting as sole sales agent for any sales made under the Sales Agreement for a 3% commission on gross proceeds. The common stock will be sold at prevailing market prices at the time of the sale, and, as a result, prices may vary. Unless otherwise terminated earlier, the Sales Agreement continues until all shares available under the Sales Agreement have been sold. No shares were sold under the Sales Agreement as of June 30, 2023.

The Company may offer additional securities under its Shelf Registration Statement from time to time in response to market conditions or other circumstances if it believes such a plan of financing is in the best interests of its stockholders.

In February 2022, as a result of the completion of the second year of the three-year vesting period for restricted stock units granted in February 2020, an aggregate of 32,666 time-based restricted stock units vested and were settled in shares of the Company’s common stock (see Note 14, Stock-Based Compensation).

- Definition

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

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+ Details