Aptinyx (APTX) 10-Q 8 Nov 22 2022 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2022	Nov. 02, 2022
Document and Entity Information
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2022
Document Transition Report	false
Entity File Number	001-38535
Entity Registrant Name	Aptinyx Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	47-4626057
Entity Address, Address Line One	909 Davis Street
Entity Address, Address Line Two	Suite 600
Entity Address, City or Town	Evanston
Entity Address, State or Province	IL
Entity Address, Postal Zip Code	60201
City Area Code	847
Local Phone Number	871-0377
Title of 12(b) Security	Common Stock, par value $0.01 per share
Trading Symbol	APTX
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	true
Entity Ex Transition Period	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		67,715,718
Entity Central Index Key	0001674365
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	Q3

Condensed Balance Sheets

Condensed Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 66,584	$ 106,124
Restricted cash	179	197
Prepaid expenses and other current assets	7,187	8,422
Total current assets	73,950	114,743
Other assets	2,219
Property and equipment, net	36	185
Total assets	76,205	114,928
Current liabilities:
Accounts payable	474	622
Accrued expenses and other current liabilities	2,220	5,064
Total current liabilities	2,694	5,686
Term loan, non-current	24,709	14,155
Other long-term liabilities	10	331
Total liabilities	27,413	20,172
Commitments and contingencies (see Note 12)
Stockholders' equity:
Preferred stock, $0.01 par value, 10,000 shares authorized and no shares issued and outstanding as of September 30, 2022 and December 31, 2021
Common stock, $0.01 par value, 150,000 shares authorized as of September 30, 2022 and December 31, 2021, 67,716 issued and outstanding as of September 30, 2022 and December 31, 2021	677	677
Additional paid-in capital	388,799	381,966
Accumulated deficit	(340,684)	(287,887)
Total stockholders' equity	48,792	94,756
Total liabilities and stockholders' equity	$ 76,205	$ 114,928

Condensed Balance Sheets (Paren

Condensed Balance Sheets (Parenthetical) - $ / shares shares in Thousands	Sep. 30, 2022	Dec. 31, 2021
Condensed Balance Sheets
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized	10,000	10,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	150,000	150,000
Common stock, shares issued	67,716	67,716
Common stock, shares outstanding	67,716	67,716

Condensed Statements of Operati

Condensed Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Revenues:
Collaboration revenue				$ 1,000
Type of Revenue [Extensible List]	aptx:CollaborationRevenueMember	aptx:CollaborationRevenueMember	aptx:CollaborationRevenueMember	aptx:CollaborationRevenueMember
Operating expenses:
Research and development	$ 10,008	$ 16,278	$ 35,519	$ 41,388
General and administrative	4,649	4,928	15,622	14,974
Total operating expenses	14,657	21,206	51,141	56,362
Loss from operations	(14,657)	(21,206)	(51,141)	(55,362)
Other (income) expense, net	(208)	(47)	(432)	(158)
Interest expense	854	72	2,088	72
Net loss and comprehensive loss	$ (15,303)	$ (21,231)	$ (52,797)	$ (55,276)
Net loss per share attributable to common stockholders, basic (in dollars per share)	$ (0.23)	$ (0.31)	$ (0.78)	$ (0.82)
Net loss per share attributable to common stockholders, diluted (in dollars per share)	$ (0.23)	$ (0.31)	$ (0.78)	$ (0.82)
Weighted-average number of common shares outstanding, basic (in shares)	67,716	67,716	67,716	67,053
Weighted-average number of common shares outstanding, diluted (in shares)	67,716	67,716	67,716	67,053

Condensed Statements of Cash Fl

Condensed Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Cash flows from operating activities:
Net loss	$ (52,797)	$ (55,276)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization expense	119	488
Change in fair value of derivative liability associated with contingently issuable warrants	(115)
Non-cash interest expense related to term loan	562	19
Stock-based compensation expense	6,627	7,395
Changes in operating assets and liabilities:
Prepaid expenses and other assets	(754)	1,258
Accounts receivable		257
Accounts payable	(147)	1,818
Accrued expenses and other liabilities	(2,802)	(324)
Net cash used in operating activities	(49,307)	(44,365)
Cash flows from investing activities:
Proceeds from sale of property and equipment		122
Net cash provided by investing activities		122
Cash flows from financing activities:
Proceeds from stock options exercised		133
Repurchase of shares for tax withholdings		(912)
Proceeds from issuance of term loan, net of issuance costs paid to lender	10,000	14,638
Payment of debt issuance costs	(21)	(38)
Proceeds from at the market offering, net of sales commission		14,615
Payment of offering costs	(230)	(5)
Net cash provided by financing activities	9,749	28,431
Net decrease in cash, cash equivalents and restricted cash	(39,558)	(15,812)
Cash, cash equivalents and restricted cash, at beginning of period	106,321	141,299
Cash, cash equivalents and restricted cash, at end of period	66,763	125,487
Supplemental disclosure of cash flow information:
Cash paid for interest	1,415
Supplemental disclosure of non-cash investing and financing activities:
Deferred offering costs not yet paid		114
Debt issuance costs not yet paid		39
Recognition of derivative liability associated with contingently issuable warrants		287
Issuance of warrants in connection with term loan financing	$ 206	$ 255

Condensed Statements of Stockho

Condensed Statements of Stockholders' Equity - USD ($) $ in Thousands	ATM Offering Common stock	ATM Offering Additional paid-in capital	ATM Offering	Common stock	Additional paid-in capital	Accumulated deficit	Total
Stockholders' (deficit) equity beginning balance at Dec. 31, 2020				$ 633	$ 358,277	$ (213,001)	$ 145,909
Stockholders' (deficit) equity shares beginning balance at Dec. 31, 2020				63,257,000
Stockholders' (Deficit) Equity Rollforward
Issuance of common stock upon vesting of restricted stock				$ 11	(11)
Issuance of common stock upon vesting of restricted stock (in shares)				1,089,000
Repurchase of shares for tax withholdings				$ (3)	(909)		(912)
Repurchase of shares for tax withholdings (in shares)				(347,000)
Stock-based compensation					7,395		7,395
Issuance of warrants in connection with term loan financing					255		255
Issuance of common stock	$ 36	$ 14,502	$ 14,538
Issuance of common stock (in shares)	3,630,000		3,629,458
Issuance of common stock upon exercise of stock options					133		133
Issuance of common stock upon exercise of stock options (in shares)				87,000
Net loss						(55,276)	(55,276)
Stockholders' (deficit) equity ending balance at Sep. 30, 2021				$ 677	379,642	(268,277)	112,042
Stockholders' (deficit) equity shares ending balance at Sep. 30, 2021				67,716,000
Stockholders' (deficit) equity beginning balance at Jun. 30, 2021				$ 677	377,125	(247,046)	130,756
Stockholders' (deficit) equity shares beginning balance at Jun. 30, 2021				67,716,000
Stockholders' (Deficit) Equity Rollforward
Stock-based compensation					2,262		2,262
Issuance of warrants in connection with term loan financing					255		255
Net loss						(21,231)	(21,231)
Stockholders' (deficit) equity ending balance at Sep. 30, 2021				$ 677	379,642	(268,277)	112,042
Stockholders' (deficit) equity shares ending balance at Sep. 30, 2021				67,716,000
Stockholders' (deficit) equity beginning balance at Dec. 31, 2021				$ 677	381,966	(287,887)	$ 94,756
Stockholders' (deficit) equity shares beginning balance at Dec. 31, 2021				67,716,000			67,716,000
Stockholders' (Deficit) Equity Rollforward
Stock-based compensation					6,627		$ 6,627
Issuance of warrants in connection with term loan financing					206		206
Net loss						(52,797)	(52,797)
Stockholders' (deficit) equity ending balance at Sep. 30, 2022				$ 677	388,799	(340,684)	$ 48,792
Stockholders' (deficit) equity shares ending balance at Sep. 30, 2022				67,716,000			67,716,000
Stockholders' (deficit) equity beginning balance at Jun. 30, 2022				$ 677	386,803	(325,381)	$ 62,099
Stockholders' (deficit) equity shares beginning balance at Jun. 30, 2022				67,716,000
Stockholders' (Deficit) Equity Rollforward
Stock-based compensation					1,996		1,996
Net loss						(15,303)	(15,303)
Stockholders' (deficit) equity ending balance at Sep. 30, 2022				$ 677	$ 388,799	$ (340,684)	$ 48,792
Stockholders' (deficit) equity shares ending balance at Sep. 30, 2022				67,716,000			67,716,000

Condensed Statements of Stock_2

Condensed Statements of Stockholders' Equity (Parenthetical) $ in Thousands	9 Months Ended
	Sep. 30, 2021 USD ($)
Sales commissions and other offering costs	$ 5
Follow-on Public Offering
Sales commissions and other offering costs	$ 529

Organization

Organization	9 Months Ended
	Sep. 30, 2022
Organization
Organization	1. Organization Description of business Aptinyx Inc. (the “Company” or “Aptinyx”) was incorporated in Delaware on June 24, 2015, and maintains its headquarters in Evanston, Illinois. Aptinyx is a clinical-stage biopharmaceutical company focused on the discovery, development, and commercialization of novel, proprietary, synthetic small molecules for the treatment of brain and nervous system disorders. Aptinyx has a platform for discovering proprietary compounds that work through a novel mechanism: modulation of N-methyl-D-aspartate receptors (“NMDAr”), which are vital to normal and effective brain and nervous system functions. This mechanism has applicability across numerous nervous system disorders. Liquidity and capital resources On July 1, 2019, the Company entered into a Sales Agreement (the “2019 Sales Agreement”) with Cowen and Company, LLC (“Cowen”) pursuant to which the Company may offer and sell shares of its common stock with an aggregate offering price of up to $50.0 million under an “at the market” offering program (the “2019 ATM Offering”). The 2019 Sales Agreement provides that Cowen will be entitled to a sales commission equal to 3.0% of the gross sales price per share of all shares sold under the 2019 ATM Offering. To date, the Company has sold an aggregate of 5,120,940 shares under the 2019 ATM Offering at a weighted-average price of $3.99 per share for net proceeds of $20.4 million after deducting sales commission and other offering expenses, including 3,629,458 shares for net proceeds of $14.5 million during the nine months ended September 30, 2021. ​ On September 15, 2021, the Company entered into a Loan and Security agreement (the “Loan Agreement”) with K2 HealthVentures LLC (“Lender”). The Loan Agreement provides up to $50.0 million principal in term loans, $15.0 million of which was funded at the time the Company entered into the agreement and $10.0 million of which was funded on March 14, 2022. See Note 7 for additional details regarding the Loan Agreement. ​ On September 16, 2021, the Company entered into a Sales Agreement (the “2021 Sales Agreement”) with Cowen pursuant to which the Company may offer and sell shares of its common stock with an aggregate offering price of up to $50.0 million under an “at the market” offering program (the “2021 ATM Offering”) and which supersedes the 2019 Sales Agreement and 2019 ATM Offering. The 2021 Sales Agreement provides that Cowen will be entitled to a sales commission equal to 3.0% of the gross sales price per share of all shares sold under the 2021 ATM Offering. As of the date of these financial statements, no shares of common stock have been issued and sold pursuant to the 2021 Sales Agreement. ​ On March 24, 2022, the Company entered into an amendment to the 2021 Sales Agreement (the “2022 Sales Agreement”) pursuant to which the Company may offer and sell shares of its common stock with an aggregate offering price of up to $75.0 million under an “at the market” offering program (the “2022 ATM Offering”) and which supersedes the 2021 Sales Agreement and 2021 ATM Offering. The 2022 Sales Agreement provides that Cowen will be entitled to a sales commission equal to 3.0% of the gross sales price per share of all shares sold under the 2022 ATM Offering. As of the date of these financial statements, no shares of common stock have been issued and sold pursuant to the 2022 Sales Agreement. ​ As of September 30, 2022, the Company had cash and cash equivalents of $66.6 million, which the Company believes will be sufficient to funds its planned operations for a period of at least twelve months from the date of issuance of these condensed financial statements.

Summary of significant accounti

Summary of significant accounting policies	9 Months Ended
	Sep. 30, 2022
Summary of significant accounting policies
Summary of significant accounting policies	2. Basis of presentation The condensed financial statements of the Company included herein have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission (the “SEC”). Certain information and footnote disclosures normally included in financial statements prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) have been condensed or omitted from this report, as is permitted by such rules and regulations. The accompanying condensed financial statements reflect all adjustments consisting of normal, recurring adjustments that are necessary for a fair presentation of the financial position, results of operations and cash flows for the interim periods presented. Interim results are not necessarily indicative of results for a full year. Accordingly, these condensed financial statements should be read in conjunction with the financial statements included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2021 (the “Annual Report”) filed with the SEC on March 23, 2022. From time to time, new accounting pronouncements are issued by the Financial Accounting Standards Board (“FASB”), or other standard setting bodies and adopted by the Company as of the specified effective date. Unless otherwise discussed, the impact of recently issued standards that are not yet effective will not have a material impact on the Company’s financial statements upon adoption. Under the Jumpstart Our Business Startups Act of 2012, as amended (the “JOBS Act”), the Company meets the definition of an emerging growth company, and has elected the extended transition period for complying with new or revised accounting standards, which delays the adoption of these accounting standards until they would apply to private companies. Use of estimates The condensed financial statements are prepared in conformity with GAAP. This process requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities as of the date of the financial statements and the reported amounts of expenses during the reporting period. Actual results could differ from those estimates. Risk and uncertainties The Company’s future results of operations involve a number of risks and uncertainties. Factors that could affect the Company’s future operating results and cause actual results to vary materially from expectations include, but are not limited to, uncertainty of: the impact of COVID-19 on future clinical study results, the scope, timing, rate of progress, and expense of the Company’s ongoing as well as any additional preclinical studies, clinical studies, and other research and development activities, clinical study enrollment rate or design, the manufacturing of the Company’s product candidates, significant and changing government regulation, and the timing and receipt of any regulatory approvals. Significant accounting policies The Company’s significant accounting policies are described herein and in Note 3, “Summary of significant accounting policies,” in the Annual Report. There have been no material changes to the significant accounting policies during the nine months ended September 30, 2022. Recently issued accounting pronouncement In February 2016, the FASB issued ASU No. 2016-02, Leases fiscal years beginning after December 15, 2022, and early adoption is permitted. The Company does not anticipate the adoption of these amendments will have a material impact on the financial statements. Prior Period Reclassifications Certain amounts in prior periods may have been reclassified to conform with current period presentation. Interest expense is now presented separately in the condensed statements of operations, and previously was a component of other (income) expense, net. These reclassifications did not affect net loss in any period presented.

Supplemental financial informat

Supplemental financial information	9 Months Ended
	Sep. 30, 2022
Supplemental financial information
Supplemental financial information	3. Supplemental financial information Cash, cash equivalents and restricted cash Cash and cash equivalents consist of cash and, if applicable, highly liquid investments with an original maturity of three months or less when purchased. The following table provides a reconciliation of cash, cash equivalents, and restricted cash reported within the balance sheets that sum to the total of the same such amounts shown in the condensed statements of cash flows (in thousands). ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of ​ As of ​ ​ ​ September 30, ​ December 31, ​ ​ 2022 2021 Cash and cash equivalents ​ $ 66,584 ​ $ 106,124 ​ Short-term restricted cash ​ 179 ​ 197 ​ Total cash, cash equivalents, and restricted cash shown in the statements of cash flows ​ $ 66,763 ​ $ 106,321 ​ ​ Prepaid expenses and other current assets ​ Prepaid expenses and other current assets consist of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of ​ As of ​ ​ ​ September 30, ​ December 31, ​ ​ 2022 2021 Prepaid clinical $ 3,041 ​ $ 4,693 Prepaid insurance ​ ​ 1,529 ​ ​ 1,122 ​ Prepaid manufacturing costs ​ ​ 2,261 ​ ​ 2,241 ​ Other prepaid expenses and current assets 356 ​ 366 Total prepaid expenses and other current assets $ 7,187 ​ $ 8,422 ​ Accrued expenses and other current liabilities ​ Accrued expenses and other current liabilities consist of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of ​ As of ​ ​ ​ September 30, ​ December 31, ​ ​ 2022 2021 Employee-related expenses ​ $ 867 ​ $ 2,567 ​ Development costs and sponsored research ​ 455 ​ 1,347 ​ Clinical trials ​ 131 ​ 810 ​ Other ​ 767 ​ 340 ​ Total accrued expenses and other current liabilities ​ $ 2,220 ​ $ 5,064 ​ ​

Research collaboration agreemen

Research collaboration agreement with Allergan	9 Months Ended
	Sep. 30, 2022
Research collaboration agreement with Allergan
Research collaboration agreement with Allergan	4. Research collaboration agreement with Allergan On July 24, 2015, the Company entered into a Research Collaboration Agreement (“RCA”) with Naurex Inc., a subsidiary of Allergan plc (“Allergan”), which became a wholly owned subsidiary of AbbVie Inc. in May 2020. The RCA was focused on the research and discovery of small molecules that modulate NMDArs. Under the terms of the agreement, the RCA terminated upon the earlier of (i) 180 days after a predetermined anniversary of the effective date of the RCA and (ii) the date on which Allergan exercised the last of three options to acquire molecules from a pool of eligible compounds, in both cases (clauses (i) and (ii)) subject to potential extension if and as required for the Company to transfer to Allergan information and technology related to compounds that were licensed by Allergan. The jointly funded research activities and option exercise period under the RCA, including the associated payments by Allergan to the Company, came to their contractual conclusions in accordance with the agreement in August 2020 and February 2021, respectively. Under the terms of the agreement, Allergan was to pay the Company $1.0 million for each option exercised by Allergan. On February 23, 2021, Allergan exercised its option to acquire exclusive rights to develop and commercialize AGN-281705 within a predefined set of indications. For the nine months ended September 30, 2021, the Company recognized the $1.0 million non-refundable milestone payment within collaboration revenue in the statements of operations as there were no remaining performance obligations associated with the optioned compound.

Fair value measurements

Fair value measurements	9 Months Ended
	Sep. 30, 2022
Fair value measurements
Fair value measurements	5. Fair value measurements ASC 820, Fair Value Measurement ● Level 1 inputs are quoted prices (unadjusted) in active markets for identical assets or liabilities; ● Level 2 inputs are inputs other than quoted prices included within Level 1 that are observable for the asset or liability, either directly or indirectly; and ● Level 3 inputs are unobservable inputs that reflect the Company’s own assumptions about the assumptions market participants would use in pricing the asset or liability. Financial assets and liabilities are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. To the extent that the valuation is based on models or inputs that are less observable or unobservable in the market, the determination of fair value requires more judgment. Accordingly, the degree of judgment exercised by the Company in determining fair value is greatest for instruments categorized in Level 3. A financial instrument’s level within the fair value hierarchy is based on the lowest level of any input that is significant to the fair value measurement. The carrying values reported in the Company’s balance sheets for cash and cash equivalents, restricted cash, accounts receivable, accounts payable, and accrued expenses are reasonable estimates of their fair values due to the short-term nature of these items. Assets and liabilities measured at fair value on a recurring basis as of September 30, 2022, are as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, ​ ​ ​ ​ ​ ​ ​ 2022 Level 1 Level 2 Level 3 Assets ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Money market funds, included in cash and cash equivalents ​ $ 65,991 ​ $ 65,991 ​ $ — ​ $ — Money market funds, included in restricted cash ​ ​ 179 ​ ​ 179 ​ — ​ — Total Assets ​ $ 66,170 ​ $ 66,170 ​ $ — ​ $ — Liabilities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Derivative liability, included in other long-term liabilities ​ $ 10 ​ $ — ​ $ — ​ $ 10 Total Liabilities ​ $ 10 ​ $ — ​ $ — ​ $ 10 ​ Assets measured at fair value on a recurring basis as of December 31, 2021, are as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ ​ ​ ​ ​ ​ 2021 Level 1 Level 2 Level 3 Assets ​ ​ ​ ​ Money market funds, included in cash and cash equivalents ​ $ 103,859 ​ $ 103,859 ​ $ — ​ $ — Money market funds, included in restricted cash ​ ​ 197 ​ ​ 197 ​ — ​ — Total Assets ​ $ 104,056 ​ $ 104,056 ​ $ — ​ $ — Liabilities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Derivative liability, included in other long-term liabilities ​ $ 331 ​ $ — ​ $ — ​ $ 331 Total Liabilities ​ $ 331 ​ $ — ​ $ — ​ $ 331 ​

Property and equipment, net

Property and equipment, net	9 Months Ended
	Sep. 30, 2022
Property and equipment, net
Property and equipment, net	​ 6. Property and equipment, net Property and equipment are as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of ​ As of ​ ​ ​ September 30, ​ December 31, ​ ​ ​ 2022 2021 Office equipment and furniture ​ 152 ​ 152 ​ Laboratory equipment ​ 401 ​ 401 ​ Leasehold improvements ​ 979 ​ 979 ​ Less accumulated depreciation ​ (1,496) ​ (1,347) ​ Property and equipment, net ​ $ 36 ​ $ 185 ​ ​ Depreciation expense was less than $0.1 million and $0.1 million for each of the three months ended September 30, 2022 and 2021, respectively, and $0.1 million and $0.5 million for the nine months ended September 30, 2022 and 2021, respectively. The Company disposed of certain laboratory equipment during the nine months ended September 30, 2021, that were fully depreciated at the time of disposal.

Debt

Debt	9 Months Ended
	Sep. 30, 2022
Debt
Debt	7. Debt On September 15, 2021, the Company entered into a Loan and Security Agreement (the “Loan Agreement”) with K2 HealthVentures LLC (the “Lender”). The Lender has agreed to make available to the Company term loans in an aggregate principal amount of up to $50.0 million under the Loan Agreement. The Company plans to use the proceeds of the term loans to support clinical development as well as for working capital and general corporate purposes. The Loan Agreement provides a term loan commitment of $50.0 million in four potential tranches: (i) a $15.0 million term loan facility funded on September 15, 2021 (the “First Tranche Term Loan”); (ii) a $10.0 million term loan facility (the “Second Tranche Term Loan”) funded on March 14, 2022; (iii) a $10.0 million term loan facility (the “Third Tranche Term Loan”) available at the Company’s option between July 1, 2022, and December 1, 2022, subject to the draw of the Second Tranche Term Loan and positive Phase 2 clinical data from NYX-2925 or NYX-458 and progression of another clinical asset; and (iv) a $15.0 million term loan facility (the “Fourth Tranche Term Loan”) available through July 1, 2023, at the Company’s option but subject to review of financial and clinical plans and Lender’s Investment Committee approval. All four of these term loans have a maturity date of September 1, 2025. Borrowings under all four term loan facilities bear interest at a floating per annum rate equal to the greater of (i) 7.95% and (ii) the Prime Rate plus 4.70% . The Company is permitted to make interest-only payments on the First Tranche Term Loan for the first 24 months following the funding date. The interest-only period can be extended by an additional 12 months , subject to the funding of the Second Tranche Term Loan and the funding of the Third Tranche Term Loan. The term of the combined facility will be 48 months , with repayment in monthly installments commencing at the end of the resulting interest-only period as outlined above through the end of the 48-month term. The Company is obligated to pay a final fee equal to 6.45% of the aggregate amount of the term loans funded (“Exit Fee”), to occur upon the earliest of (i) the maturity date, (ii) the acceleration of the term loans, and (iii) the prepayment of the term loans. The Company has the option to prepay all, but not less than all, of the outstanding principal balance of the term loans under the Loan Agreement. If the Company prepays all of the term loans prior to the maturity date, it will pay the Lender a prepayment penalty fee based on a percentage of the outstanding principal balance, equal to 3% if the payment occurs on or before 24 months after the initial funding date, 2% if the prepayment occurs more than 24 months after, but on or before 36 months after the initial funding date, or 1% if the prepayment occurs more than 36 months after the initial funding date. The Company also is obligated to pay the Lender an origination fee of 0.8% of all term loans funded at the time of funding. The Lender may, at its option, elect to convert any portion of no more than $4 million of the then outstanding term loan amount and all accrued and unpaid interest thereon into shares of the Company’s common stock at a conversion price of the lesser of $4.25 per share and the price per share of the common stock in the Company’s next equity offering in which the Company receives at least $20.0 million of gross proceeds . The Company determined that the embedded conversion option is not required to be separated from the term loan. The embedded conversion option meets the derivative accounting scope exception since the embedded conversion option is indexed to the Company’s own common stock and qualifies for classification within stockholders’ equity. The Company’s obligations under the Loan Agreement are secured by a first priority security interest in substantially all of its assets. The Loan Agreement contains customary representations and warranties, and also includes customary events of default, including payment default, breach of covenants, change of control, and material adverse effects. The Loan Agreement restricts certain activities, such as disposing of the Company’s business or certain assets, incurring additional debt or liens or making payments on other debt, making certain investments and declaring dividends, acquiring or merging with another entity, engaging in transactions with affiliates or encumbering intellectual property, among others. There are no financial covenants associated with the Loan Agreement. The Company was in compliance with all non-financial covenants under the Loan Agreement as of September 30, 2022. Upon the occurrence of an event of default, a default interest rate of an additional 5% per annum may be applied to the outstanding loan balances, and the Lender may declare all outstanding obligations immediately due and payable and exercise all of its rights and remedies as set forth in the Loan Agreement and under applicable law. The Company recorded interest expense related to the Loan Agreement of $0.9 million for the three months ended September 30, 2022, and $2.1 million for the nine months ended September 30, 2022. Future principal debt payments of the term loans funded as of September 30, 2022, are as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ 2023 ​ $ 2,828 2024 ​ 12,112 2025 ​ 10,060 Total principal payments ​ 25,000 Exit Fee ​ ​ 1,613 Total principal payments and Exit Fee ​ ​ 26,613 Less: Unamortized debt discount related to warrants ​ ​ (378) Less: Unamortized debt discount related to Exit Fee ​ ​ (1,201) Less: Unamortized debt issuance costs ​ (325) Term loan, non-current ​ $ 24,709 ​

Stock incentive plans

Stock incentive plans	9 Months Ended
	Sep. 30, 2022
Stock incentive plans
Stock incentive plans	8. Stock incentive plans On June 5, 2018, the Company’s stockholders approved the 2018 Stock Option and Incentive Plan (the “2018 Plan”), which became effective on June 20, 2018. Stock-based compensation expense Non-cash stock-based compensation expense recognized in the accompanying condensed statements of operations relating to stock options, restricted stock awards, and restricted stock units for the three and nine months ended September 30, 2022 and 2021, was as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended ​ Nine months ended ​ ​ ​ September 30, ​ September 30, ​ ​ 2022 2021 2022 2021 Research and development ​ $ 277 ​ $ 634 ​ $ 1,096 ​ $ 2,047 ​ General and administrative ​ 1,719 ​ 1,628 ​ 5,531 ​ 5,348 ​ Total stock‑based compensation expense ​ $ 1,996 ​ $ 2,262 ​ $ 6,627 ​ $ 7,395 ​ ​ Stock options The table below summarizes activity related to stock options (in thousands, except per share amounts): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ‑ ​ ​ ​ ​ ​ ​ Weighted ‑ ​ average ​ ​ ​ ​ ​ ​ ​ average ​ remaining ​ Aggregate ​ ​ ​ ​ exercise ​ contractual ​ intrinsic Options ​ Shares ​ price ​ term ​ value Outstanding, December 31, 2021 10,713 ​ $ 5.36 8.07 ​ $ 718 Granted 2,307 ​ 2.96 ​ Exercised ​ — ​ ​ — ​ ​ ​ ​ ​ Forfeited and canceled (1,099) ​ 3.94 ​ Outstanding, September 30, 2022 ​ 11,921 ​ $ 5.03 ​ 7.52 ​ $ — Vested and expected to vest at September 30, 2022 ​ 11,921 ​ $ 5.03 ​ 7.52 ​ $ — Exercisable at September 30, 2022 6,541 ​ $ 6.61 6.45 ​ $ — ​ During the nine months ended September 30, 2022 and 2021, the Company granted 2.3 million and 3.2 million stock options, respectively, and these options had a weighted-average grant-date fair value of $2.26 and $2.71 per share, respectively. The weighted-average grant-date fair value of options was determined using the Black-Scholes option-pricing model. The assumptions used in the Black-Scholes option-pricing model for options granted during the nine months ended September 30, 2022, were similar to those as described in the Annual Report, except for the manner in which the expected volatility was determined. The expected volatility for the Company’s options granted during the nine months ended September 30, 2022, is based on a weighted-average of the historical volatility of share values of publicly traded companies within the biotechnology industry, which includes the historical volatility of the Company’s stock since the Company’s initial public offering. As of September 30, 2022, there was $11.3 million of total unrecognized stock-based compensation expense related to non-vested stock options, which is expected to be recognized over a weighted-average period of 2.6 years. The options have a ten-year life and generally vest over a period of four years, subject to continuous employment. Restricted stock units ​ In June 2020, the Company issued an aggregate of 205,200 restricted stock units to employees. The restricted stock units issued in 2020 vested ten months from the date of grant. Such shares were not accounted for as outstanding until they vested. Non-cash restricted stock unit award expense recognized in the accompanying condensed statements of operations was $0.0 million and $0.0 million for the three months ended September 30, 2022 and 2021, respectively, and $0.0 million and $0.8 million for the nine months ended September 30, 2022 and 2021, respectively. There were no unvested restricted stock units as of September 30, 2022.

Warrants and derivative liabili

Warrants and derivative liability	9 Months Ended
	Sep. 30, 2022
Warrants and derivative liability
Warrants and derivative liability	9. Warrants and derivative liability ​ Warrants ​ On September 15, 2021, the Company entered into the Loan Agreement with the Lender pursuant to which the Lender may provide the Company with term loans in an aggregate principal amount of up to $50.0 million. ​ On September 15, 2021, in connection with the funding of the First Tranche Term Loan, the Company issued a warrant exercisable for 147,600 shares of the Company’s common stock at an exercise price of $2.29 per share. The warrant is immediately exercisable for 147,600 shares and expires on September 15, 2031. ​ On March 14, 2022, in connection with the funding of the Second Tranche Term Loan, the Company issued a warrant exercisable for 98,399 shares of the Company’s common stock at an exercise price of $2.29 per share. The warrant is immediately exercisable for 98,399 shares and expires on September 15, 2031. ​ No warrants had been exercised as of September 30, 2022. Any shares of the Company’s common stock issued upon exercise of the warrants are permitted to be settled in unregistered shares. The warrants are classified as equity as they meet all of the conditions under GAAP for equity classification. The Company has calculated the fair value of the warrants for initial measurement and date of funding of the Second Tranche Term Loan, and reassesses whether equity classification for the warrants is appropriate upon any changes to the warrants or capital structure, at each balance sheet date. ​ The Company determined that the fair value of the warrants issued in connection with the First Tranche Term Loan and Second Tranche Term Loan was $0.3 million and $0.2 million, respectively. The specific assumptions used to determine the initial measurement of fair value of the warrants were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ First Tranche ​ Second Tranche ​ ​ Term Loan ​ Term Loan ​ ​ ​ ​ ​ ​ ​ Expected volatility 95 % ​ 93 % Expected dividends None ​ ​ None ​ Expected term 5.00 Years ​ ​ 5.00 Years ​ Risk-free rate 0.81 % ​ 2.10 % ​ ​ Derivative Liability ​ The Additional Warrants’ (as defined below) derivative liability will be remeasured each reporting period until settled or extinguished with subsequent changes in fair value recorded through other income (expense), net in the condensed statements of operations. The fair value of the Additional Warrants derivative liability was determined using a Black-Scholes option pricing model based on the same input assumptions above, with an additional assessment required for the probability that the Additional Tranche Term Loans will be funded which would trigger the issuance of the Additional Warrants. ​ The Company is conditionally obligated to issue a fixed number of additional warrants (“Additional Warrants”) in the amount of 344,398 shares of the Company’s common stock upon the funding of the Second, Third and Fourth Tranche Term Loans with the same exercise price and contractual term. The contingent obligation to issue the Additional Warrants did not meet the derivative scope exception or equity classification criteria and were accounted for as a derivative liability. The contingently issuable Additional Warrants derivative liability had an initial fair value of $ million and was recorded as additional debt discount and as a separate derivative liability within other long-term liabilities in the condensed balance sheet. ​ As a result of the funding of the Second Tranche Term Loan, the Company issued a warrant exercisable for 98,399 shares of the Company’s common stock at $2.29 per share. Upon issuing the warrants, the Company reclassified the related portion of its Additional Warrants derivative liability into equity. The remaining Additional Warrant Liability that remains outstanding was remeasured as of period end. The ​ The following table provides a reconciliation of the beginning and ending balances for the Company’s Additional Warrants derivative liability recognized in connection with the term loan measured at fair value using significant unobservable inputs (Level 3): ​ ​ ​ ​ ​ ​ ​ Additional ​ ​ Warrants Balance at December 31, 2021 ​ $ 331 Fair value of Additional Warrant Derivative Liability issued during the period ​ — Change in fair value ​ ​ (115) Derecognition ​ (206) Balance at September 30, 2022 ​ $ 10 ​ The specific assumptions used to determine the fair value of the warrants as of September 30, 2022, and December 31, 2021 were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, ​ December 31, ​ ​ 2022 ​ 2021 ​ ​ ​ ​ ​ ​ ​ Expected volatility 98 % ​ 95 % Expected dividends None ​ ​ None ​ Expected term 5.00 Years ​ ​ 5.00 Years ​ Risk-free rate 4.06 % ​ 1.26 % ​

Net loss per share

Net loss per share	9 Months Ended
	Sep. 30, 2022
Net loss per share
Net loss per share	10. Net loss per share Basic and diluted net loss per share attributable to common stockholders was calculated as follows for the three and nine months ended September 30, 2022 and 2021 (in thousands, except per share data): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended ​ Nine months ended ​ ​ ​ September 30, ​ September 30, ​ ​ 2022 2021 2022 2021 Numerator: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net loss attributable to common stockholders ​ $ (15,303) ​ $ (21,231) ​ $ (52,797) ​ $ (55,276) ​ Denominator: ​ ​ ​ ​ ​ ​ ​ Weighted-average common shares outstanding—basic and diluted ​ 67,716 ​ 67,716 ​ 67,716 ​ 67,053 ​ Net loss per share attributable to common stockholders—basic and diluted ​ $ (0.23) ​ $ (0.31) ​ $ (0.78) ​ $ (0.82) ​ ​ The following common stock equivalents outstanding as of September 30, 2022 and 2021, were excluded from the computation of diluted net loss per share attributable to common stockholders for the periods presented because including them would have been anti-dilutive (in thousands): ​ ​ ​ ​ ​ ​ ​ As of ​ ​ September 30, ​ 2022 2021 Stock options issued and outstanding 11,921 9,392 Warrants ​ 246 ​ 148 Total 12,167 9,540 ​

Income taxes

Income taxes	9 Months Ended
	Sep. 30, 2022
Income taxes
Income taxes	11. Income taxes Deferred tax assets and liabilities are determined based on the difference between the financial statement and tax bases of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. Valuation allowances are provided if based upon the weight of available evidence, it is more likely than not that some or all of the deferred tax assets will not be realized. The Company has evaluated the positive and negative evidence bearing upon the realizability of its deferred tax assets, including its net operating losses. Based on its history of operating losses, the Company believes that it is more likely than not that the benefit of its deferred tax assets will not be realized. Accordingly, the Company has provided a full valuation allowance for deferred tax assets as of September 30, 2022, and December 31, 2021. ​ ​

Commitments and contingencies

Commitments and contingencies	9 Months Ended
	Sep. 30, 2022
Commitments and contingencies
Commitments and contingencies	12. Commitments and contingencies Contingencies From time to time, the Company may be subject to occasional lawsuits, investigations, and claims arising out of the normal conduct of business. The Company has no significant pending or threatened litigation as of September 30, 2022. Indemnifications In the normal course of business, the Company enters into contracts that contain a variety of indemnifications with its employees, licensors, suppliers and service providers. Further, the Company indemnifies its directors and officers who are, or were, serving at the Company’s request in such capacities. The Company’s maximum exposure under these arrangements is unknown as of September 30, 2022. The Company does not anticipate recognizing any significant losses relating to these arrangements. Leases The Company enters into various non-cancelable, operating lease agreements for its facilities and equipment in order to conduct its operations. The Company expenses rent on a straight-line basis over the life of the lease and has recorded deferred rent on the Company’s balance sheets within both accrued expenses and other current liabilities and other long-term liabilities. Total rent expense, inclusive of lease incentives, under all the operating lease agreements amounted to $0.2 million for each of the three months ended September 30, 2022 and 2021, and $0.7 million and $0.6 million for the nine months ended September 30, 2022 and 2021.

Summary of significant accoun_2

Summary of significant accounting policies (Policies)	9 Months Ended
	Sep. 30, 2022
Summary of significant accounting policies
Basis of presentation	Basis of presentation The condensed financial statements of the Company included herein have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission (the “SEC”). Certain information and footnote disclosures normally included in financial statements prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) have been condensed or omitted from this report, as is permitted by such rules and regulations. The accompanying condensed financial statements reflect all adjustments consisting of normal, recurring adjustments that are necessary for a fair presentation of the financial position, results of operations and cash flows for the interim periods presented. Interim results are not necessarily indicative of results for a full year. Accordingly, these condensed financial statements should be read in conjunction with the financial statements included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2021 (the “Annual Report”) filed with the SEC on March 23, 2022. From time to time, new accounting pronouncements are issued by the Financial Accounting Standards Board (“FASB”), or other standard setting bodies and adopted by the Company as of the specified effective date. Unless otherwise discussed, the impact of recently issued standards that are not yet effective will not have a material impact on the Company’s financial statements upon adoption. Under the Jumpstart Our Business Startups Act of 2012, as amended (the “JOBS Act”), the Company meets the definition of an emerging growth company, and has elected the extended transition period for complying with new or revised accounting standards, which delays the adoption of these accounting standards until they would apply to private companies.
Use of estimates	Use of estimates The condensed financial statements are prepared in conformity with GAAP. This process requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities as of the date of the financial statements and the reported amounts of expenses during the reporting period. Actual results could differ from those estimates.
Risk and uncertainties	Risk and uncertainties The Company’s future results of operations involve a number of risks and uncertainties. Factors that could affect the Company’s future operating results and cause actual results to vary materially from expectations include, but are not limited to, uncertainty of: the impact of COVID-19 on future clinical study results, the scope, timing, rate of progress, and expense of the Company’s ongoing as well as any additional preclinical studies, clinical studies, and other research and development activities, clinical study enrollment rate or design, the manufacturing of the Company’s product candidates, significant and changing government regulation, and the timing and receipt of any regulatory approvals.
Recently issued accounting pronouncement	Recently issued accounting pronouncement In February 2016, the FASB issued ASU No. 2016-02, Leases fiscal years beginning after December 15, 2022, and early adoption is permitted. The Company does not anticipate the adoption of these amendments will have a material impact on the financial statements.
Prior Period Reclassifications	Prior Period Reclassifications Certain amounts in prior periods may have been reclassified to conform with current period presentation. Interest expense is now presented separately in the condensed statements of operations, and previously was a component of other (income) expense, net. These reclassifications did not affect net loss in any period presented.

Supplemental financial inform_2

Supplemental financial information (Tables)	9 Months Ended
	Sep. 30, 2022
Supplemental financial information
Schedule of cash, cash equivalents and restricted cash	. The following table provides a reconciliation of cash, cash equivalents, and restricted cash reported within the balance sheets that sum to the total of the same such amounts shown in the condensed statements of cash flows (in thousands). ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of ​ As of ​ ​ ​ September 30, ​ December 31, ​ ​ 2022 2021 Cash and cash equivalents ​ $ 66,584 ​ $ 106,124 ​ Short-term restricted cash ​ 179 ​ 197 ​ Total cash, cash equivalents, and restricted cash shown in the statements of cash flows ​ $ 66,763 ​ $ 106,321 ​
Schedule of prepaid expenses and other current assets	Prepaid expenses and other current assets consist of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of ​ As of ​ ​ ​ September 30, ​ December 31, ​ ​ 2022 2021 Prepaid clinical $ 3,041 ​ $ 4,693 Prepaid insurance ​ ​ 1,529 ​ ​ 1,122 ​ Prepaid manufacturing costs ​ ​ 2,261 ​ ​ 2,241 ​ Other prepaid expenses and current assets 356 ​ 366 Total prepaid expenses and other current assets $ 7,187 ​ $ 8,422
Schedule of accrued expenses and other current liabilities	Accrued expenses and other current liabilities consist of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of ​ As of ​ ​ ​ September 30, ​ December 31, ​ ​ 2022 2021 Employee-related expenses ​ $ 867 ​ $ 2,567 ​ Development costs and sponsored research ​ 455 ​ 1,347 ​ Clinical trials ​ 131 ​ 810 ​ Other ​ 767 ​ 340 ​ Total accrued expenses and other current liabilities ​ $ 2,220 ​ $ 5,064 ​

Fair value measurements (Tables

Fair value measurements (Tables)	9 Months Ended
	Sep. 30, 2022
Fair value measurements
Schedule of assets and liabilities measured at fair value	Assets and liabilities measured at fair value on a recurring basis as of September 30, 2022, are as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, ​ ​ ​ ​ ​ ​ ​ 2022 Level 1 Level 2 Level 3 Assets ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Money market funds, included in cash and cash equivalents ​ $ 65,991 ​ $ 65,991 ​ $ — ​ $ — Money market funds, included in restricted cash ​ ​ 179 ​ ​ 179 ​ — ​ — Total Assets ​ $ 66,170 ​ $ 66,170 ​ $ — ​ $ — Liabilities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Derivative liability, included in other long-term liabilities ​ $ 10 ​ $ — ​ $ — ​ $ 10 Total Liabilities ​ $ 10 ​ $ — ​ $ — ​ $ 10 ​ Assets measured at fair value on a recurring basis as of December 31, 2021, are as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, ​ ​ ​ ​ ​ ​ ​ 2021 Level 1 Level 2 Level 3 Assets ​ ​ ​ ​ Money market funds, included in cash and cash equivalents ​ $ 103,859 ​ $ 103,859 ​ $ — ​ $ — Money market funds, included in restricted cash ​ ​ 197 ​ ​ 197 ​ — ​ — Total Assets ​ $ 104,056 ​ $ 104,056 ​ $ — ​ $ — Liabilities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Derivative liability, included in other long-term liabilities ​ $ 331 ​ $ — ​ $ — ​ $ 331 Total Liabilities ​ $ 331 ​ $ — ​ $ — ​ $ 331

Property and equipment, net (Ta

Property and equipment, net (Tables)	9 Months Ended
	Sep. 30, 2022
Property and equipment, net
Schedule of property and equipment, net	Property and equipment are as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of ​ As of ​ ​ ​ September 30, ​ December 31, ​ ​ ​ 2022 2021 Office equipment and furniture ​ 152 ​ 152 ​ Laboratory equipment ​ 401 ​ 401 ​ Leasehold improvements ​ 979 ​ 979 ​ Less accumulated depreciation ​ (1,496) ​ (1,347) ​ Property and equipment, net ​ $ 36 ​ $ 185 ​

Debt (Tables)

Debt (Tables)	9 Months Ended
	Sep. 30, 2022
Debt
Schedule of maturities of long-term debt	Future principal debt payments of the term loans funded as of September 30, 2022, are as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ 2023 ​ $ 2,828 2024 ​ 12,112 2025 ​ 10,060 Total principal payments ​ 25,000 Exit Fee ​ ​ 1,613 Total principal payments and Exit Fee ​ ​ 26,613 Less: Unamortized debt discount related to warrants ​ ​ (378) Less: Unamortized debt discount related to Exit Fee ​ ​ (1,201) Less: Unamortized debt issuance costs ​ (325) Term loan, non-current ​ $ 24,709

Stock incentive plans (Tables)

Stock incentive plans (Tables)	9 Months Ended
	Sep. 30, 2022
Stock incentive plans
Allocation of stock-based compensation expenses	Non-cash stock-based compensation expense recognized in the accompanying condensed statements of operations relating to stock options, restricted stock awards, and restricted stock units for the three and nine months ended September 30, 2022 and 2021, was as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended ​ Nine months ended ​ ​ ​ September 30, ​ September 30, ​ ​ 2022 2021 2022 2021 Research and development ​ $ 277 ​ $ 634 ​ $ 1,096 ​ $ 2,047 ​ General and administrative ​ 1,719 ​ 1,628 ​ 5,531 ​ 5,348 ​ Total stock‑based compensation expense ​ $ 1,996 ​ $ 2,262 ​ $ 6,627 ​ $ 7,395 ​
Summary of stock option activity	The table below summarizes activity related to stock options (in thousands, except per share amounts): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ‑ ​ ​ ​ ​ ​ ​ Weighted ‑ ​ average ​ ​ ​ ​ ​ ​ ​ average ​ remaining ​ Aggregate ​ ​ ​ ​ exercise ​ contractual ​ intrinsic Options ​ Shares ​ price ​ term ​ value Outstanding, December 31, 2021 10,713 ​ $ 5.36 8.07 ​ $ 718 Granted 2,307 ​ 2.96 ​ Exercised ​ — ​ ​ — ​ ​ ​ ​ ​ Forfeited and canceled (1,099) ​ 3.94 ​ Outstanding, September 30, 2022 ​ 11,921 ​ $ 5.03 ​ 7.52 ​ $ — Vested and expected to vest at September 30, 2022 ​ 11,921 ​ $ 5.03 ​ 7.52 ​ $ — Exercisable at September 30, 2022 6,541 ​ $ 6.61 6.45 ​ $ —

Warrants and derivative liabi_2

Warrants and derivative liability (Tables)	9 Months Ended
	Sep. 30, 2022
Class of Warrant or Right [Line Items]
Schedule of fair value of the warrants or rights	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, ​ December 31, ​ ​ 2022 ​ 2021 ​ ​ ​ ​ ​ ​ ​ Expected volatility 98 % ​ 95 % Expected dividends None ​ ​ None ​ Expected term 5.00 Years ​ ​ 5.00 Years ​ Risk-free rate 4.06 % ​ 1.26 %
Schedule of reconciliation of liabilities with significant unobservable inputs	​ ​ ​ ​ ​ ​ ​ Additional ​ ​ Warrants Balance at December 31, 2021 ​ $ 331 Fair value of Additional Warrant Derivative Liability issued during the period ​ — Change in fair value ​ ​ (115) Derecognition ​ (206) Balance at September 30, 2022 ​ $ 10
Loan agreement
Class of Warrant or Right [Line Items]
Schedule of fair value of the warrants or rights	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ First Tranche ​ Second Tranche ​ ​ Term Loan ​ Term Loan ​ ​ ​ ​ ​ ​ ​ Expected volatility 95 % ​ 93 % Expected dividends None ​ ​ None ​ Expected term 5.00 Years ​ ​ 5.00 Years ​ Risk-free rate 0.81 % ​ 2.10 %

Net loss per share (Tables)

Net loss per share (Tables)	9 Months Ended
	Sep. 30, 2022
Net loss per share
Schedule of basic and diluted net loss per share attributable to common stockholders calculation	Basic and diluted net loss per share attributable to common stockholders was calculated as follows for the three and nine months ended September 30, 2022 and 2021 (in thousands, except per share data): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended ​ Nine months ended ​ ​ ​ September 30, ​ September 30, ​ ​ 2022 2021 2022 2021 Numerator: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Net loss attributable to common stockholders ​ $ (15,303) ​ $ (21,231) ​ $ (52,797) ​ $ (55,276) ​ Denominator: ​ ​ ​ ​ ​ ​ ​ Weighted-average common shares outstanding—basic and diluted ​ 67,716 ​ 67,716 ​ 67,716 ​ 67,053 ​ Net loss per share attributable to common stockholders—basic and diluted ​ $ (0.23) ​ $ (0.31) ​ $ (0.78) ​ $ (0.82) ​
Schedule of anti-dilutive securities excluded from computation of diluted net loss per share	The following common stock equivalents outstanding as of September 30, 2022 and 2021, were excluded from the computation of diluted net loss per share attributable to common stockholders for the periods presented because including them would have been anti-dilutive (in thousands): ​ ​ ​ ​ ​ ​ ​ As of ​ ​ September 30, ​ 2022 2021 Stock options issued and outstanding 11,921 9,392 Warrants ​ 246 ​ 148 Total 12,167 9,540

Organization (Details)

Organization (Details) - USD ($) $ / shares in Units, $ in Thousands						9 Months Ended		39 Months Ended
	Mar. 24, 2022	Mar. 14, 2022	Sep. 16, 2021	Sep. 15, 2021	Jul. 01, 2019	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Dec. 31, 2021
Organization
Proceeds from public offering, net of underwriters' discounts							$ 14,615
Cash and cash equivalents						$ 66,584		$ 66,584	$ 106,124
Expected period of sufficient funds for planned operations						12 months
Proceeds from issuance of term loan						$ 10,000	$ 14,638
ATM Offering
Organization
Number of common stock shares newly issued							3,629,458	5,120,940
Public offering price of the shares sold						$ 3.99		$ 3.99
Proceeds from public offering, net of underwriters' discounts							$ 14,500	$ 20,400
Threshold shares agreed to be sold					$ 50,000
Sales commission percentage					3%
2021 ATM Offering
Organization
Number of common stock shares newly issued						0
Threshold shares agreed to be sold			$ 50,000
Sales commission percentage			3%
2022 ATM Offering
Organization
Number of common stock shares newly issued						0
Threshold shares agreed to be sold	$ 75,000
Sales commission percentage	3%
Loan agreement
Organization
Maximum borrowing capacity				$ 50,000
First Tranche Term Loan
Organization
Proceeds from issuance of term loan				15,000
Principal amount				$ 15,000
Second Tranche Term Loan
Organization
Proceeds from issuance of term loan		$ 10,000
Principal amount		$ 10,000

Summary of significant accoun_3

Summary of significant accounting policies (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Summary of significant accounting policies
Other (income) expense, net	$ (208)	$ (47)	$ (432)	$ (158)
Interest expense	$ 854	$ 72	$ 2,088	$ 72

Supplemental financial inform_3

Supplemental financial information - Cash, cash equivalents and restricted cash (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021	Sep. 30, 2021	Dec. 31, 2020
Supplemental financial information
Cash and cash equivalents	$ 66,584	$ 106,124
Short-term restricted cash	179	197
Total cash, cash equivalents, and restricted cash shown in the statements of cash flows	$ 66,763	$ 106,321	$ 125,487	$ 141,299

Supplemental financial inform_4

Supplemental financial information - Prepaid expenses and other current assets (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Supplemental financial information
Prepaid clinical	$ 3,041	$ 4,693
Prepaid insurance	1,529	1,122
Prepaid manufacturing costs	2,261	2,241
Other prepaid expenses and current assets	356	366
Total prepaid expenses and other current assets	$ 7,187	$ 8,422

Supplemental financial inform_5

Supplemental financial information - Accrued expenses and other current liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Supplemental financial information
Employee-related expenses	$ 867	$ 2,567
Development costs and sponsored research	455	1,347
Clinical trials	131	810
Other	767	340
Total accrued expenses and other current liabilities	$ 2,220	$ 5,064

Research collaboration agreem_2

Research collaboration agreement with Allergan (Details) - RCA $ in Millions		9 Months Ended
	Jul. 24, 2015 USD ($) Option	Sep. 30, 2021 USD ($)
Research collaboration agreement with Allergan
Agreement term	180 days
Number of options to acquire molecules | Option	3
Payment of option exercise fee	$ 1
Milestone payment		$ 1

Fair value measurements (Detail

Fair value measurements (Details) - Recurring - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Fair value measurements
Total Assets	$ 66,170	$ 104,056
Derivative liability, included in other long-term liabilities	10	331
Total Liabilities	10	331
Money market funds, included in cash and cash equivalents
Fair value measurements
Money market funds	65,991	103,859
Money market funds, included in restricted cash
Fair value measurements
Money market funds	179	197
Level 1
Fair value measurements
Total Assets	66,170	104,056
Level 1 | Money market funds, included in cash and cash equivalents
Fair value measurements
Money market funds	65,991	103,859
Level 1 | Money market funds, included in restricted cash
Fair value measurements
Money market funds	179	197
Level 3
Fair value measurements
Derivative liability, included in other long-term liabilities	10	331
Total Liabilities	$ 10	$ 331

Property and equipment, net (De

Property and equipment, net (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Property and equipment
Less accumulated depreciation	$ (1,496)		$ (1,496)		$ (1,347)
Property and equipment, net	36		36		185
Depreciation		$ 100	100	$ 500
Maximum
Property and equipment
Depreciation	100
Office equipment and furniture
Property and equipment
Property and equipment, gross	152		152		152
Laboratory equipment
Property and equipment
Property and equipment, gross	401		401		401
Leasehold improvements
Property and equipment
Property and equipment, gross	$ 979		$ 979		$ 979

Debt (Details)

Debt (Details) $ / shares in Units, $ in Thousands			3 Months Ended		9 Months Ended
	Mar. 14, 2022 USD ($)	Sep. 15, 2021 USD ($) tranche $ / shares	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)
Debt Instrument [Line Items]
Proceeds from issuance of term loan					$ 10,000	$ 14,638
Interest expense			$ 854	$ 72	2,088	$ 72
Loan agreement
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 50,000
Number of tranches | tranche		4
Interest rate		7.95%
Term of debt		48 months
Final fee percentage		6.45%
Origination fee		0.80%
Conversion price | $ / shares		$ 4.25
Equity offering proceeds threshold to set debt conversion price		$ 20,000
Additional default interest rate		5%
Interest expense			$ 900		$ 2,100
Loan agreement | Minimum
Debt Instrument [Line Items]
Threshold amount for conversion		$ 4,000
Loan agreement | Prepayment occurs on or before 24 months after initial funding
Debt Instrument [Line Items]
Prepayment penalty percentage		3%
Threshold period in which prepayment occurs		24 months
Loan agreement | Prepayment occurs more than 24 months and on or before 36 months after initial funding
Debt Instrument [Line Items]
Prepayment penalty percentage		2%
Loan agreement | Prepayment occurs more than 24 months and on or before 36 months after initial funding | Minimum
Debt Instrument [Line Items]
Threshold period in which prepayment occurs		24 months
Loan agreement | Prepayment occurs more than 24 months and on or before 36 months after initial funding | Maximum
Debt Instrument [Line Items]
Threshold period in which prepayment occurs		36 months
Loan agreement | Prepayment occurs more than 36 months after initial funding
Debt Instrument [Line Items]
Prepayment penalty percentage		1%
Threshold period in which prepayment occurs		36 months
Loan agreement | Prime
Debt Instrument [Line Items]
Spread (as a percent)		4.70%
First Tranche Term Loan
Debt Instrument [Line Items]
Proceeds from issuance of term loan		$ 15,000
Principal amount		$ 15,000
Period for which interest only payment is permitted		24 months
Additional period for which interest only payment can be extended		12 months
Second Tranche Term Loan
Debt Instrument [Line Items]
Proceeds from issuance of term loan	$ 10,000
Principal amount	$ 10,000
Third Tranche Term Loan Facility
Debt Instrument [Line Items]
Principal amount		$ 10,000
Third Tranche Term Loan For 15 Million [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 15,000

Debt - Future Principal Debt Pa

Debt - Future Principal Debt Payments on The Loan Payable (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Long-term Debt, Rolling Maturity [Abstract]
2023	$ 2,828
2024	12,112
2025	10,060
Total principal payments	25,000
Exit Fee	1,613
Total principal payments and Exit Fee	26,613
Less: Unamortized debt discount related to warrants	(378)
Less: Unamortized debt discount related to Exit Fee	(1,201)
Less: Unamortized debt issuance costs	(325)
Term loan, non-current	$ 24,709	$ 14,155

Stock incentive plans - Stock-b

Stock incentive plans - Stock-based compensation expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 1,996	$ 2,262	$ 6,627	$ 7,395
Research and development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	277	634	1,096	2,047
General and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 1,719	$ 1,628	$ 5,531	$ 5,348

Stock incentive plans - Activit

Stock incentive plans - Activity related to stock options (Details) - Stock options - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	9 Months Ended		12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Shares
Outstanding, at the beginning of the period	10,713
Granted	2,307	3,200
Forfeited and canceled	(1,099)
Outstanding, at the end of the period	11,921		10,713
Vested and expected to vest	11,921
Exercisable	6,541
Weighted-average exercise price
Outstanding, at the beginning of the period	$ 5.36
Granted	2.96
Forfeited and canceled	3.94
Outstanding, at the end of the period	5.03		$ 5.36
Vested and expected to vest	5.03
Exercisable at the end of the period	$ 6.61
Weighted-average remaining contractual term
Weighted-average remaining contractual term	7 years 6 months 7 days		8 years 25 days
Vested and expected to vest	7 years 6 months 7 days
Exercisable	6 years 5 months 12 days
Aggregate intrinsic value
Outstanding, at the beginning of the period	$ 718
Outstanding, at the end of the period			$ 718
Weighted-average grant date fair value per share	$ 2.26	$ 2.71
Unrecognized stock-based compensation related to non-vested stock options	$ 11,300
Expenses recognized over a weighted-average period (in years)	2 years 7 months 6 days
Term of award	10 years
Vesting period	4 years

Stock incentive plans - Restric

Stock incentive plans - Restricted stock units (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		9 Months Ended
	Jun. 30, 2020	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Shares
Non-cash restricted stock unit award expense recognized		$ 1,996	$ 2,262	$ 6,627	$ 7,395
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	10 months
Shares
Unvested restricted stock outstanding		0		0
Issued (in shares)	205,200
Non-cash restricted stock unit award expense recognized		$ 0	$ 0	$ 0	$ 800

Warrants and derivative liabi_3

Warrants and derivative liability (Details)			9 Months Ended
	Sep. 30, 2022 USD ($) shares	Sep. 15, 2021 USD ($) item $ / shares shares	Sep. 30, 2022 USD ($)	Mar. 14, 2022 USD ($) $ / shares shares	Dec. 31, 2021 USD ($)
Class of Warrant or Right [Line Items]
Warrants exercised | shares	0
Expected volatility
Class of Warrant or Right [Line Items]
Warrants and rights outstanding, measurement input	98		98		95
Expected dividends
Class of Warrant or Right [Line Items]
Warrants and rights outstanding, measurement input	0		0		0
Expected term
Class of Warrant or Right [Line Items]
Warrants and rights outstanding, measurement input	5		5		5
Risk-free rate
Class of Warrant or Right [Line Items]
Warrants and rights outstanding, measurement input	4.06		4.06		1.26
Loan agreement
Class of Warrant or Right [Line Items]
Maximum borrowing capacity		$ 50,000,000
First Tranche Term Loan
Class of Warrant or Right [Line Items]
Issued warrant exercisable | shares		147,600
Exercise price | $ / shares		$ 2.29
Derivative liability, included in other long-term liabilities		$ 300,000
First Tranche Term Loan | Expected volatility
Class of Warrant or Right [Line Items]
Warrants and rights outstanding, measurement input		95
First Tranche Term Loan | Expected dividends
Class of Warrant or Right [Line Items]
Warrants and rights outstanding, measurement input		0
First Tranche Term Loan | Expected term
Class of Warrant or Right [Line Items]
Warrants and rights outstanding, measurement input		5
First Tranche Term Loan | Risk-free rate
Class of Warrant or Right [Line Items]
Warrants and rights outstanding, measurement input		0.81
Second Tranche Term Loan
Class of Warrant or Right [Line Items]
Issued warrant exercisable | shares				98,399
Exercise price | $ / shares				$ 2.29
Change in fair value of warrants			$ 100,000
Derivative liability, included in other long-term liabilities				$ 200,000
Second Tranche Term Loan | Expected volatility
Class of Warrant or Right [Line Items]
Warrants and rights outstanding, measurement input				93
Second Tranche Term Loan | Expected dividends
Class of Warrant or Right [Line Items]
Warrants and rights outstanding, measurement input				0
Second Tranche Term Loan | Expected term
Class of Warrant or Right [Line Items]
Warrants and rights outstanding, measurement input				5
Second Tranche Term Loan | Risk-free rate
Class of Warrant or Right [Line Items]
Warrants and rights outstanding, measurement input				2.10
Additional Warrants
Class of Warrant or Right [Line Items]
Warrants obligated to be issued upon the funding of the second, third and fourth tranche term loans | item		344,398
Derivative liability, included in other long-term liabilities	$ 300,000		$ 300,000

Warrants and derivative liabi_4

Warrants and derivative liability - Reconciliation of company's additional warrants (Details) - Additional Warrants $ in Thousands	9 Months Ended
	Sep. 30, 2022 USD ($)
Reconciliation of company's additional warrants derivative liability
Balance at beginning of period	$ 331
Change in fair value	(115)
Derecognition	(206)
Balance at end of period	$ 10

Net loss per share (Details)

Net loss per share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Numerator:
Net loss attributable to common stockholders	$ (15,303)	$ (21,231)	$ (52,797)	$ (55,276)
Denominator:
Weighted-average number of common shares outstanding, basic (in shares)	67,716	67,716	67,716	67,053
Weighted-average number of common shares outstanding, diluted (in shares)	67,716	67,716	67,716	67,053
Net loss per share attributable to common stockholders, basic (in dollars per share)	$ (0.23)	$ (0.31)	$ (0.78)	$ (0.82)
Net loss per share attributable to common stockholders, diluted (in dollars per share)	$ (0.23)	$ (0.31)	$ (0.78)	$ (0.82)

Net loss per share - Anti-dilut

Net loss per share - Anti-dilutive securities (Details) - shares shares in Thousands	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Common stock equivalents outstanding excluded from the computation of diluted net loss per share attributable to common stockholders
Outstanding anti-dilutive securities excluded from computation of diluted net loss per share	12,167	9,540
Stock options
Common stock equivalents outstanding excluded from the computation of diluted net loss per share attributable to common stockholders
Outstanding anti-dilutive securities excluded from computation of diluted net loss per share	11,921	9,392
Warrants
Common stock equivalents outstanding excluded from the computation of diluted net loss per share attributable to common stockholders
Outstanding anti-dilutive securities excluded from computation of diluted net loss per share	246	148

Commitments and contingencies (

Commitments and contingencies (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Commitments and contingencies
Rent expense inclusive of lease incentives	$ 0.2	$ 0.2	$ 0.7	$ 0.6