0001628280-23-016425 | 10-Q | XBRL Viewer | Neoleukin Therapeutics INC

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Condensed Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Current assets
Cash and cash equivalents	$ 35,494	$ 37,887
Short-term investments	47,942	58,497
Other current assets	2,200	2,750
Total current assets	85,636	99,134
Property and equipment, net	2,489	6,163
Operating lease right-of-use assets	9,430	9,715
Other non-current assets	905	936
Total assets	98,460	115,948
Current liabilities
Accounts payable and accrued liabilities	5,421	9,547
Operating lease liabilities	1,431	1,375
Finance lease liabilities	304	140
Total current liabilities	7,156	11,062
Non-current operating lease liabilities	9,940	10,322
Non-current finance lease liabilities	7	233
Total liabilities	17,103	21,617
Stockholders’ equity
Common stock - $0.000001 par value - authorized, 100,000,000 as of March 31, 2023 and December 31, 2022; issued and outstanding, 42,818,346 as of March 31, 2023 and 42,648,346 as of December 31, 2022	0	0
Preferred stock - $0.000001 par value - authorized, 5,000,000 as of March 31, 2023 and December 31, 2022; issued and outstanding, 0 as of March 31, 2023 and December 31, 2022	0	0
Additional paid-in capital	546,598	545,407
Accumulated other comprehensive income (loss)	18	(21)
Accumulated deficit	(465,259)	(451,055)
Total stockholders’ equity	81,357	94,331
Total liabilities and stockholders’ equity	$ 98,460	$ 115,948

Equity - Additional Information (Details) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2023 USD ($) offering $ / shares shares	Mar. 31, 2022 USD ($) $ / shares shares	Dec. 31, 2022 $ / shares shares	Nov. 04, 2021 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, shares authorized (in shares)	100,000,000		100,000,000
Common stock, par value (in dollars per share) \| $ / shares	$ 0.000001		$ 0.000001
Common stock, shares issued (in shares)	42,818,346		42,648,346
Common stock, shares outstanding (in shares)	42,818,346		42,648,346
Percentage of outstanding stock per stockholder, maximum	9.99%
Percentage of outstanding stock per stockholder, upon notice, maximum	19.99%
Warrants, notice period for nominal cash consideration	61 days
Unrecognized stock-based compensation cost \| $	$ 2.0
Unrecognized stock-based compensation cost, weighted-average period recognized	2 years 18 days
Shares issued upon exercises of stock options (in shares)	0	36,500
Aggregate intrinsic value of options exercised \| $		$ 0.1
Weighted average grant date fair value for options granted in period (in dollars per share) \| $ / shares	$ 0.43	$ 1.75
Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued upon exercises of stock options (in shares)		36,500
Shares issued upon vesting of restricted stock units (in shares)	170,000
2020 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock shares reserved for issuance under employee stock purchase plan (in shares)	759,936
Shares issuable under 2020 ESPP \| 2020 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
ESPP max contribution rate	15.00%
ESPP, purchase price of common stock, percent of market price	85.00%
ESPP number of offerings per year \| offering	2
ESPP offering period	6 months
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units vested (in shares)	(180,000)
Shares outstanding and unissued (in shares)	10,000
Equity Offering Sales Agreement
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Purchase Price \| $				$ 40.0
Prefunded Warrants
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding pre-funded warrants (in shares)	12,663,010	12,663,010
Exercise price of pre-funded warrants (in dollars per share) \| $ / shares	$ 0.000001

Cover Page - shares	3 Months Ended
Cover Page - shares	Mar. 31, 2023	May 04, 2023
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2023
Document Transition Report	false
Entity File Number	001-36327
Entity Registrant Name	Neoleukin Therapeutics, Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	98-0542593
Entity Address, Address Line One	188 East Blaine Street
Entity Address, Address Line Two	Suite 450
Entity Address, City or Town	Seattle
Entity Address, State or Province	WA
Entity Address, Postal Zip Code	98102
City Area Code	866
Local Phone Number	245-0312
Title of 12(b) Security	Common Stock, par value $0.000001
Trading Symbol	NLTX
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		42,828,346
Amendment Flag	false
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	Q1
Entity Central Index Key	0001404644
Current Fiscal Year End Date	--12-31

Condensed Statements of Operations and Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Operating expenses
Research and development	$ 7,690	$ 10,701
General and administrative	4,027	4,664
Impairment of property and equipment	3,418	0
Total operating expenses	15,135	15,365
Loss from operations	(15,135)	(15,365)
Interest income	945	13
Other income (loss), net	(14)	1
Net loss	(14,204)	(15,351)
Comprehensive income (loss):
Unrealized gain on available-for-sale securities	39	0
Comprehensive loss	$ (14,165)	$ (15,351)
Net loss per share – basic (in dollars per share)	$ (0.26)	$ (0.28)
Net loss per share – diluted (in dollars per share)	$ (0.26)	$ (0.28)
Basic weighted average common shares outstanding (in shares)	55,420,912	55,143,537
Diluted weighted average common shares outstanding (in shares)	55,420,912	55,143,537

Equity - Summary of Stock-based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total stock-based compensation expense	$ 1,191	$ 2,446
Research and development expenses
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total stock-based compensation expense	256	1,264
General and administrative expenses
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total stock-based compensation expense	$ 935	$ 1,182

Summary of significant accounting policies (Policies)	3 Months Ended
Summary of significant accounting policies (Policies)	Mar. 31, 2023
Accounting Policies [Abstract]
Basis of presentation	Basis of presentation The accompanying unaudited condensed financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) and pursuant to the rules and regulations of the United States Securities and Exchange Commission (“SEC”) for interim financial information. Accordingly, these financial statements do not include all of the information and footnotes required by U.S. GAAP for complete financial statements and should be read in conjunction with the audited consolidated financial statements and accompanying notes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2022, filed with the Securities and Exchange Commission on March 20, 2023. In management’s opinion, the unaudited condensed financial statements reflect all adjustments (consisting of normal recurring adjustments) necessary to present fairly the financial position of the Company as of March 31, 2023, and results of operations and cash flows for all periods presented. The interim results presented are not necessarily indicative of results that can be expected for the full year ending December 31, 2023. The Company reclassified prior year interest income in the condensed statements of operations and comprehensive income (loss) to conform to current year presentation. This reclassification had no effect on net loss or comprehensive loss.
Use of estimates and assumptions	Use of estimates and assumptionsThe preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reporting period. Significant areas requiring estimates include valuation and recognition of stock-based compensation, the incremental borrowing rate utilized in the measurement of operating and finance lease liabilities, amortization/depreciation and impairment of property and equipment, and pre-clinical, clinical, and other accruals. Actual results could differ from those estimates.
Property and equipment	Property and equipment Property and equipment are recorded at cost and are amortized using the straight-line basis over a range of three to seven years. The Company reviews the carrying value of property and equipment for impairment whenever events and circumstances indicate that the carrying value of an asset may not be recoverable from the estimated future cash flows expected to result from its use and eventual disposition. In cases where undiscounted expected future cash flows are less than the carrying value, an impairment loss is recognized equal to an amount by which the carrying value exceeds the fair value of assets. The factors considered by management in performing this assessment include current operating results, trends and prospects, the manner in which the property is used, and the effects of obsolescence, demand, competition, and other economic factors. Based on management’s assessment, as a result of the corporate restructuring announced in March 2023, including the decision to suspend all research and development activities, there were indicators of impairment of certain property and equipment as of March 31, 2023. During the three months ended March 31, 2023, the Company recorded $3.4 million in impairment charges. There were no indicators of impairment of property and equipment as of December 31, 2022.
Leases	Leases At contract inception, the Company determines if the contract is or contains a lease. Lease liabilities are recognized on the lease commencement date based on the estimated present value of lease payments over the lease term. To determine the present value of the lease payments, the Company utilizes its estimated incremental borrowing rate based on information available at the lease commencement date as the interest rate implicit in the lease is typically not readily determinable. The related right-of-use assets are recorded net of any lease incentives received. Variable lease cost primarily includes building operating expenses as charged to the Company by its landlords and payments for lessor-owned assets that are not covered by a tenant improvement allowance. The Company includes options to extend the lease in its lease liability and right-of-use asset when it is reasonably certain that it will exercise that option. None of the Company's options to extend the rental term of any of its existing leases were considered reasonably certain as of March 31, 2023. For leases of office space and equipment, the Company has elected to not separate the lease components from the non-lease components. For leases with a lease term of 12 months or less and which do not include an option to purchase the underlying asset, the Company has elected to recognize the lease payments in the statement of operations on a straight-line basis over the lease term.
Fair value of financial instruments	Fair value of financial instruments The carrying amounts of certain of the Company’s financial instruments, including cash and cash equivalents, restricted cash, receivables, accounts payable and other liabilities, approximate their fair values because of their nature and/or short maturities. Certain of the Company’s financial instruments are measured at fair value on a recurring basis. The Company determines the fair value of those financial instruments based upon the fair value hierarchy, which prioritizes valuation inputs based on the observable nature of those inputs. The three levels of the fair value hierarchy are as follows: Level 1 - quoted prices (unadjusted) in active markets for identical assets or liabilities that can be accessed on the measurement date Level 2 - quoted prices (in non-active markets or in active markets for similar assets or liabilities), observable inputs other than quoted prices and inputs that are not directly observable but are corroborated by observable market data Level 3 - unobservable inputs that are supported by little or no market activity and that are significant to determining the fair value of the assets or liabilities
Investments	InvestmentsThe Company’s short-term investments consist entirely of investments in U.S. treasury securities. These investments are classified as available-for-sale debt securities and are therefore reported at fair value in the condensed balance sheets. Unrealized gains and losses are included in accumulated other comprehensive income (loss). There were no realized gains or losses on investments for the three months ended March 31, 2023 and March 31, 2022. The Company assesses investments for impairment at each reporting period. An investment is considered impaired when the amortized cost basis exceeds the fair value. When this is the case, the Company assesses whether the impairment is credit-related or noncredit-related based on various factors. When an impairment, or a portion of an impairment, is considered credit-related, an allowance for credit losses is recorded.
Net loss per share	Net loss per shareBasic net loss per share is calculated by dividing the net loss by the weighted average number of shares of common stock outstanding for the period, without consideration for common stock equivalents. Common stock equivalents are included in the calculation of diluted earnings per share only in periods of net income and are excluded in the calculation of diluted net loss per share in periods of net loss as their inclusion would be anti-dilutive.
Accounting for stock-based compensation	Accounting for stock-based compensation The Company has issued stock options and restricted stock units (“RSUs”). The Company measures the cost of services received in exchange for an award of equity instruments based on the grant-date fair value of the award. The cost of such award is recognized on a straight-line basis over the requisite service period, which is generally the vesting period. The Company accounts for forfeitures as they occur. The Company utilizes newly issued shares to satisfy option exercises, the vesting of RSUs, and 2020 Employee Stock Purchase Plan ("2020 ESPP") purchases. The Company estimates the fair value of options using the Black-Scholes option pricing model on the grant date. This approximation uses assumptions regarding a number of inputs that requires management to make significant estimates and judgments. The expected term represents the period that the Company’s stock-based awards are expected to be outstanding. As the Company does not have sufficient historical experience for determining the expected term of the stock option awards granted, the Company has based its expected term for awards issued to employees on the simplified method, which represents the average period from vesting to the expiration of the stock option. In addition, the Company does not have sufficient trading history of the Company’s common stock, and therefore, the expected stock price volatility for the Company’s common stock was estimated by taking the average historical price volatility for industry peers. The Company has never declared or paid any cash dividends to common stockholders and does not presently plan to pay cash dividends in the foreseeable future. Consequently, the Company used an expected dividend yield of zero. The risk-free interest rate was based on the yields of treasury securities with maturities similar to the expected term of the options for each option group. The fair value of each RSU is measured using the closing price of the Company’s common stock on the date of grant.
Restructuring Charges	Restructuring chargesThe Company records costs and liabilities associated with exit and disposal activities in accordance with ASC 420, Exit or Disposal Cost Obligations. Restructuring charges are recorded in the period in which they are incurred. The Company evaluates and adjusts these costs as appropriate for changes in circumstances as additional information becomes available.
Recently issued and recently adopted accounting standards	Recently issued and recently adopted accounting standardsThe Company monitors and evaluates the issuance of Accounting Standards Updates ("ASUs"). No ASUs have been issued recently which impact the Company's financial statements and disclosures.

Cash, cash equivalents, and restricted cash - Schedule of Cash, Cash Equivalents, and Restricted Cash (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022	Mar. 31, 2022	Dec. 31, 2021
Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents [Abstract]
Cash and cash equivalents	$ 35,494	$ 37,887
Restricted cash	878	878
Total cash, cash equivalents, and restricted cash	$ 36,372	$ 38,765	$ 128,935	$ 143,345

Summary of significant accounting policies - Fair Value (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Money market funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Money market funds	$ 32,084	$ 33,767
Fair Value, Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total financial assets	83,004	95,737
Fair Value, Recurring \| U.S. treasury securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
U.S. treasury securities	50,920	61,970
Fair Value, Recurring \| Money market funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Money market funds	32,084	33,767
Level 1 \| Fair Value, Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total financial assets	83,004	95,737
Level 1 \| Fair Value, Recurring \| U.S. treasury securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
U.S. treasury securities	50,920	61,970
Level 1 \| Fair Value, Recurring \| Money market funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Money market funds	32,084	33,767
Level 2 \| Fair Value, Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total financial assets	0	0
Level 2 \| Fair Value, Recurring \| U.S. treasury securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
U.S. treasury securities	0	0
Level 2 \| Fair Value, Recurring \| Money market funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Money market funds	0	0
Level 3 \| Fair Value, Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total financial assets	0	0
Level 3 \| Fair Value, Recurring \| U.S. treasury securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
U.S. treasury securities	0	0
Level 3 \| Fair Value, Recurring \| Money market funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Money market funds	$ 0	$ 0

Cash, cash equivalents, and restricted cash (Tables)

3 Months Ended

Mar. 31, 2023

Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents [Abstract]

Schedule of Cash and Cash Equivalents

The following table provides a reconciliation of cash, cash equivalents, and restricted cash in the condensed balance sheets that sum to the total of the same such amounts shown in the condensed statements of cash flows:


(in thousands)	March 31, 2023		December 31, 2022
Cash and cash equivalents	$	35,494	$	37,887
Restricted cash	878		878
Total cash, cash equivalents, and restricted cash	$	36,372	$	38,765

Restrictions on Cash and Cash Equivalents


(in thousands)	March 31, 2023		December 31, 2022
Cash and cash equivalents	$	35,494	$	37,887
Restricted cash	878		878
Total cash, cash equivalents, and restricted cash	$	36,372	$	38,765

Summary of significant accounting policies (Tables)

3 Months Ended

Mar. 31, 2023

Accounting Policies [Abstract]

Schedule of Fair Value, Assets

The following table presents information about the Company's financial instruments that are measured at fair value on a recurring basis:


	March 31, 2023
(in thousands)	Total		Level 1		Level 2		Level 3
Financial assets
Money market funds	$	32,084	$	32,084	$	—	$	—
U.S. treasury securities	50,920		50,920		—		—
Total financial assets	$	83,004	$	83,004	$	—	$	—


	December 31, 2022
(in thousands)	Total		Level 1		Level 2		Level 3
Financial assets
Money market funds	$	33,767	$	33,767	$	—	$	—
U.S. treasury securities	61,970		61,970		—		—
Total financial assets	$	95,737	$	95,737	$	—	$	—

Nature of operations	3 Months Ended
Nature of operations	Mar. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of operations	Nature of operationsNeoleukin Therapeutics, Inc. (“Neoleukin” or “the Company”) has historically been a biopharmaceutical company creating next generation immunotherapies for cancer, inflammation, and autoimmunity using de novo protein design technology. Based on decisions made by our Board of Directors in November 2022 and March 2023, the Company has restructured operations to significantly reduce its workforce, discontinue development of NL-201, a de novo protein that was in Phase 1 clinical trial for the treatment of cancer, and suspend all research and development activities in order to conserve capital and focus on other strategic alternatives for the Company. Such alternatives may include a sale, merger, divestiture of assets, licensing or other strategic transaction

Equity - Schedule of Weighted Average Assumptions (Details)	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Equity [Abstract]
Expected volatility	85.95%	83.18%
Expected dividends	0.00%	0.00%
Expected terms (years)	6 years 14 days	6 years 25 days
Risk free rate	3.46%	1.95%

Net loss per share - Schedule of Potentially Dilutive Shares From Diluted Net Loss Per Share (Details) - shares	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities excluded from computation of earnings per share (in shares)	5,383,202	9,053,182
Outstanding stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities excluded from computation of earnings per share (in shares)	5,322,605	8,297,921
Restricted stock units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities excluded from computation of earnings per share (in shares)	47,250	710,000
Shares issuable under 2020 ESPP
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities excluded from computation of earnings per share (in shares)	13,347	45,261

Investments

3 Months Ended

Mar. 31, 2023

Investments, Debt and Equity Securities [Abstract]

Investments

The Company's investments consist of the following:


	March 31, 2023
(in thousands)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Cash equivalents:
Money market funds	$	32,084	$	—	$	—	$	32,084
U.S. treasury securities - due within 3 months	2,995		1		—		2,996
Short-term investments:
U.S. treasury securities - due within 1 year	47,925		17		—		47,942
Total	$	83,004	$	18	$	—	$	83,022


	December 31, 2022
(in thousands)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Cash equivalents:
Money market funds	$	33,767	$	—	$	—	$	33,767
U.S. treasury securities - due within 3 months	3,473		—		—		3,473
Short-term investments:
U.S. treasury securities - due within 1 year	58,518		6		(27)		58,497
Total	$	95,758	$	6	$	(27)	$	95,737

Condensed Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
Condensed Statements of Cash Flows - USD ($) $ in Thousands	Mar. 31, 2023	Mar. 31, 2022
Operating activities
Net loss	$ (14,204)	$ (15,351)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation	1,191	2,446
Depreciation and amortization	329	411
Impairment of property and equipment	3,418	0
Amortization of operating lease right-of-use assets	286	250
Amortization and accretion of premiums/discounts on available-for-sale securities	(531)	0
Loss on disposal of property and equipment	190	0
Changes in operating assets and liabilities:
Other current assets and other non-current assets	552	(803)
Accounts payable and accrued liabilities	(3,938)	(769)
Operating lease liabilities	(326)	(275)
Net cash used in operating activities	(13,033)	(14,091)
Investing activities
Purchases of property and equipment	(419)	(452)
Purchases of available-for-sale securities	(28,375)	0
Proceeds from maturities of available-for-sale securities	39,500	0
Net cash provided by (used in) investing activities	10,706	(452)
Financing activities
Proceeds from exercise of stock options	0	134
Payments on finance lease obligations	(66)	(1)
Net cash provided by (used in) financing activities	(66)	133
Net change in cash, cash equivalents, and restricted cash during the period	(2,393)	(14,410)
Cash, cash equivalents, and restricted cash, beginning of period	38,765	143,345
Cash, cash equivalents, and restricted cash, end of period	36,372	128,935
Supplemental disclosure of non-cash investing and financing activities:
Purchases of property and equipment unpaid at period-end	$ 99	$ 91

Restructurings and impairment charges (Tables)

3 Months Ended

Mar. 31, 2023

Restructuring and Related Activities [Abstract]

Summary of Restructuring Charges

A summary of the accrued liabilities activity recorded in connection with the November 2022 Reduction and March 2023 Restructuring Plan for the three months ended March 31, 2023 is as follows (in thousands):


	Accrued at December 31, 2022		Charges		Amounts Paid		Accrued at March 31, 2023
Employee severance, benefits, and related costs
November 2022 Reduction	$	1,041	$	327	$	(490)	$	878
March 2023 Restructuring Plan	—		$	1,640	$	(344)	$	1,296
Total	$	1,041	$	1,967	$	(834)	$	2,174

Net loss per share

3 Months Ended

Mar. 31, 2023

Earnings Per Share [Abstract]

Net loss per share

Net loss per shareThe Company excluded the following potentially dilutive shares from diluted net loss per share as the effect would have been anti-dilutive for all periods presented:


	Three Months Ended March 31,
	2023	2022
Outstanding stock options	5,322,605	8,297,921
Restricted stock units	47,250	710,000
Shares issuable under 2020 ESPP	13,347	45,261
	5,383,202	9,053,182

Cash, cash equivalents, and restricted cash - Additional Information (Details) $ in Millions	Mar. 31, 2023 USD ($)
Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents [Abstract]
Cash deposit	$ 0.9

Condensed Statements of Stockholders’ Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Income(Loss)	Accumulated Deficit
Balance, beginning (in shares) at Dec. 31, 2021		42,457,471
Balance, beginning at Dec. 31, 2021	$ 142,864		$ 536,362		$ (393,498)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued upon exercises of stock options (in shares)	36,500	36,500
Shares issued upon exercises of stock options	$ 134		134
Unrealized gain on available-for-sale securities	0
Stock-based compensation	2,446		2,446
Net loss	(15,351)				(15,351)
Balance, ending (in shares) at Mar. 31, 2022		42,493,971
Balance, ending at Mar. 31, 2022	130,093		538,942	$ 0	(408,849)
Balance, beginning (in shares) at Dec. 31, 2022		42,648,346
Balance, beginning at Dec. 31, 2022	$ 94,331		545,407	(21)	(451,055)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued upon exercises of stock options (in shares)	0
Shares issued upon vesting of restricted stock units (in shares)		170,000
Unrealized gain on available-for-sale securities	$ 39			39
Stock-based compensation	1,191		1,191
Net loss	(14,204)				(14,204)
Balance, ending (in shares) at Mar. 31, 2023		42,818,346
Balance, ending at Mar. 31, 2023	$ 81,357		$ 546,598	$ 18	$ (465,259)

- 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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(22))
-URI https://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 32
-Subparagraph (f)
-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8933-108599

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 4
-URI https://asc.fasb.org/extlink&oid=124431687&loc=d3e22595-107794

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(18))
-URI https://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263

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+ Details

- Definition

Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

+ References

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+ Details

Summary of significant accounting policies

3 Months Ended

Mar. 31, 2023

Accounting Policies [Abstract]

Summary of significant accounting policies

(a)Basis of presentation

The accompanying unaudited condensed financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) and pursuant to the rules and regulations of the United States Securities and Exchange Commission (“SEC”) for interim financial information. Accordingly, these financial statements do not include all of the information and footnotes required by U.S. GAAP for complete financial statements and should be read in conjunction with the audited consolidated financial statements and accompanying notes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2022, filed with the Securities and Exchange Commission on March 20, 2023.

In management’s opinion, the unaudited condensed financial statements reflect all adjustments (consisting of normal recurring adjustments) necessary to present fairly the financial position of the Company as of March 31, 2023, and results of operations and cash flows for all periods presented. The interim results presented are not necessarily indicative of results that can be expected for the full year ending December 31, 2023. The Company reclassified prior year interest income in the condensed statements of operations and comprehensive income (loss) to conform to current year presentation. This reclassification had no effect on net loss or comprehensive loss.

(b)Use of estimates and assumptions

The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reporting period. Significant areas requiring estimates include valuation and recognition of stock-based compensation, the incremental borrowing rate utilized in the measurement of operating and finance lease liabilities, amortization/depreciation and impairment of property and equipment, and pre-clinical, clinical, and other accruals. Actual results could differ from those estimates.

(c)Property and equipment

Property and equipment are recorded at cost and are amortized using the straight-line basis over a range of three to seven years.

The Company reviews the carrying value of property and equipment for impairment whenever events and circumstances indicate that the carrying value of an asset may not be recoverable from the estimated future cash flows expected to result from its use and eventual disposition. In cases where undiscounted expected future cash flows are less than the carrying value, an impairment loss is recognized equal to an amount by which the carrying value exceeds the fair value of assets. The factors considered by management in performing this assessment include current operating results, trends and prospects, the manner in which the property is used, and the effects of obsolescence, demand, competition, and other economic factors. Based on management’s assessment, as a result of the corporate restructuring announced in March 2023, including the decision to suspend all research and development activities, there were indicators of impairment of certain property and equipment as of March 31, 2023. During the three months ended March 31, 2023, the Company recorded $3.4 million in impairment charges. There were no indicators of impairment of property and equipment as of December 31, 2022.

(d)Leases

At contract inception, the Company determines if the contract is or contains a lease. Lease liabilities are recognized on the lease commencement date based on the estimated present value of lease payments over the lease term. To determine the present value of the lease payments, the Company utilizes its estimated incremental borrowing rate based on information available at the lease commencement date as the interest rate implicit in the lease is typically not readily determinable. The related right-of-use assets are recorded net of any lease incentives received. Variable lease cost primarily includes building operating expenses as charged to the Company by its landlords and payments for lessor-owned assets that are not covered by a tenant improvement allowance.

The Company includes options to extend the lease in its lease liability and right-of-use asset when it is reasonably certain that it will exercise that option. None of the Company's options to extend the rental term of any of its existing leases were considered reasonably certain as of March 31, 2023.

For leases of office space and equipment, the Company has elected to not separate the lease components from the non-lease components.

For leases with a lease term of 12 months or less and which do not include an option to purchase the underlying asset, the Company has elected to recognize the lease payments in the statement of operations on a straight-line basis over the lease term.

(e)Fair value of financial instruments

The carrying amounts of certain of the Company’s financial instruments, including cash and cash equivalents, restricted cash, receivables, accounts payable and other liabilities, approximate their fair values because of their nature and/or short maturities.

Certain of the Company’s financial instruments are measured at fair value on a recurring basis. The Company determines the fair value of those financial instruments based upon the fair value hierarchy, which prioritizes valuation inputs based on the observable nature of those inputs. The three levels of the fair value hierarchy are as follows:

Level 1 - quoted prices (unadjusted) in active markets for identical assets or liabilities that can be accessed on the measurement date

Level 2 - quoted prices (in non-active markets or in active markets for similar assets or liabilities), observable inputs other than quoted prices and inputs that are not directly observable but are corroborated by observable market data

Level 3 - unobservable inputs that are supported by little or no market activity and that are significant to determining the fair value of the assets or liabilities

The following table presents information about the Company's financial instruments that are measured at fair value on a recurring basis:


	March 31, 2023
(in thousands)	Total		Level 1		Level 2		Level 3
Financial assets
Money market funds	$	32,084	$	32,084	$	—	$	—
U.S. treasury securities	50,920		50,920		—		—
Total financial assets	$	83,004	$	83,004	$	—	$	—


	December 31, 2022
(in thousands)	Total		Level 1		Level 2		Level 3
Financial assets
Money market funds	$	33,767	$	33,767	$	—	$	—
U.S. treasury securities	61,970		61,970		—		—
Total financial assets	$	95,737	$	95,737	$	—	$	—

(f)Investments

The Company’s short-term investments consist entirely of investments in U.S. treasury securities. These investments are classified as available-for-sale debt securities and are therefore reported at fair value in the condensed balance sheets. Unrealized gains and losses are included in accumulated other comprehensive income (loss). There were no realized gains or losses on investments for the three months ended March 31, 2023 and March 31, 2022.

The Company assesses investments for impairment at each reporting period. An investment is considered impaired when the amortized cost basis exceeds the fair value. When this is the case, the Company assesses whether the impairment is credit-related or noncredit-related based on various factors. When an impairment, or a portion of an impairment, is considered credit-related, an allowance for credit losses is recorded. For the three months ended March 31, 2023, the Company recognized no year-to-date credit losses and no allowance for credit losses is recorded as of March 31, 2023. The aggregate fair value of investments with unrealized losses as of March 31, 2023 is $4.0 million.

(g)Net loss per share

Basic net loss per share is calculated by dividing the net loss by the weighted average number of shares of common stock outstanding for the period, without consideration for common stock equivalents. Common stock equivalents are included in the calculation of diluted earnings per share only in periods of net income and are excluded in the calculation of diluted net loss per share in periods of net loss as their inclusion would be anti-dilutive. Outstanding pre-funded warrants as of March 31, 2023 and March 31, 2022 are 12,663,010 and are considered outstanding as of their issuance date and are included in basic and diluted net loss per share because they are fully vested and exercisable for nominal cash consideration.

(h)Accounting for stock-based compensation

The Company has issued stock options and restricted stock units (“RSUs”). The Company measures the cost of services received in exchange for an award of equity instruments based on the grant-date fair value of the award. The cost of such award is recognized on a straight-line basis over the requisite service period, which is generally the vesting period. The Company accounts for forfeitures as they occur. The Company utilizes newly issued shares to satisfy option exercises, the vesting of RSUs, and 2020 Employee Stock Purchase Plan ("2020 ESPP") purchases.

The Company estimates the fair value of options using the Black-Scholes option pricing model on the grant date. This approximation uses assumptions regarding a number of inputs that requires management to make significant estimates and judgments. The expected term represents the period that the Company’s stock-based awards are expected to be outstanding. As the Company does not have sufficient historical experience for determining the expected term of the stock option awards granted, the Company has based its expected term for awards issued to employees on the simplified method, which represents the average period from vesting to the expiration of the stock option. In addition, the Company does not have sufficient trading history of the Company’s common stock, and therefore, the expected stock price volatility for the Company’s common stock was estimated by taking the average historical price volatility for industry peers. The Company has never declared or paid any cash dividends to common stockholders and does not presently plan to pay cash dividends in the foreseeable future. Consequently, the Company used an expected dividend yield of zero. The risk-free interest rate was based on the yields of treasury securities with maturities similar to the expected term of the options for each option group.

The fair value of each RSU is measured using the closing price of the Company’s common stock on the date of grant.

(i)Restructuring charges

The Company records costs and liabilities associated with exit and disposal activities in accordance with ASC 420, Exit or Disposal Cost Obligations. Restructuring charges are recorded in the period in which they are incurred. The Company evaluates and adjusts these costs as appropriate for changes in circumstances as additional information becomes available.

(j)Recently issued and recently adopted accounting standards

The Company monitors and evaluates the issuance of Accounting Standards Updates ("ASUs"). No ASUs have been issued recently which impact the Company's financial statements and disclosures.

Restructurings and impairment charges

3 Months Ended

Mar. 31, 2023

Restructuring and Related Activities [Abstract]

Restructurings and impairment charges

November workforce reduction

On November 14, 2022, the Company announced a corporate restructuring as a result of the strategic decision to discontinue further development of NL-201. In conjunction with this decision, the Company's Board of Directors approved a restructuring plan that included a reduction of approximately 40% of the Company's workforce (the "November 2022 Reduction").

In connection with the November 2022 Reduction, the Company expects to incur aggregate restructuring charges consisting of severance payments, benefits, and other employee related costs of $1.7 million, of which $1.4 million was recognized during the fourth quarter of 2022. The remaining $0.3 million was incurred during the three months ended March 31, 2023, all of which is included in research and development expenses in the statement of operations and comprehensive income (loss). The Company expects to pay all remaining restructuring charges associated with the November 2022 Reduction by the end of the third quarter of 2023.

March workforce reduction

On March 6, 2023, the Company's Board of Directors approved a reduction in force of the Company's workforce by approximately 70% in connection with a re-prioritization of the Company’s focus on seeking strategic alternatives to maximize stockholder value (the "March 2023 Restructuring Plan").

In connection with the March 2023 Restructuring Plan, the Company expects to incur additional aggregate restructuring charges consisting of severance payments, benefits, and other employee related costs of $1.8 million, of which $1.6 million was incurred during the three months ended March 31, 2023. The remaining restructuring costs of $0.2 million are expected to be incurred during the quarter ended June 30, 2023 due to future service requirements by certain employees entitling them to receive severance benefits. Of the $1.6 million of restructuring charges incurred during the three months ended March 31, 2023, $0.6 million is included in general and administrative expenses and $1.0 million is included in research and development expenses in the condensed statement of operations and comprehensive income (loss). The Company expects to pay all remaining restructuring charges associated with the March 2023 Restructuring Plan by the end of the first quarter of 2024.


	Accrued at December 31, 2022		Charges		Amounts Paid		Accrued at March 31, 2023
Employee severance, benefits, and related costs
November 2022 Reduction	$	1,041	$	327	$	(490)	$	878
March 2023 Restructuring Plan	—		$	1,640	$	(344)	$	1,296
Total	$	1,041	$	1,967	$	(834)	$	2,174

Impairment charges

As a result of the March 2023 Restructuring Plan, the Company determined that sufficient indicators existed to trigger the performance of an interim long-lived asset impairment analysis as of March 31, 2023. In the first quarter of 2023, the Company tested the recoverability of its asset groups for property and equipment using entity-specific undiscounted cash flows. Based on these undiscounted cash flows, the Company concluded the undiscounted future cash flows expected to result from the eventual disposition of its long-lived assets were less than the carrying value of the asset groups. Therefore, the Company measured the long-lived asset impairment as the amount by which the carrying value of the asset group exceeds its fair value and recorded an impairment charge of $3.4 million. The fair value of the asset group reflect the Company’s best estimate of what hypothetical market participants would use to determine a transaction price for the asset group which represents a Level 3 fair value measurement.

Investments (Tables)

3 Months Ended

Mar. 31, 2023

Investments, Debt and Equity Securities [Abstract]

Schedule of Investments

The Company's investments consist of the following:


	March 31, 2023
(in thousands)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Cash equivalents:
Money market funds	$	32,084	$	—	$	—	$	32,084
U.S. treasury securities - due within 3 months	2,995		1		—		2,996
Short-term investments:
U.S. treasury securities - due within 1 year	47,925		17		—		47,942
Total	$	83,004	$	18	$	—	$	83,022


	December 31, 2022
(in thousands)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Cash equivalents:
Money market funds	$	33,767	$	—	$	—	$	33,767
U.S. treasury securities - due within 3 months	3,473		—		—		3,473
Short-term investments:
U.S. treasury securities - due within 1 year	58,518		6		(27)		58,497
Total	$	95,758	$	6	$	(27)	$	95,737

Condensed Balance Sheets (Parenthetical) - $ / shares	Mar. 31, 2023	Dec. 31, 2022
Statement of Financial Position [Abstract]
Common stock, par value (in dollars per share)	$ 0.000001	$ 0.000001
Common stock, shares authorized (in shares)	100,000,000	100,000,000
Common stock, shares issued (in shares)	42,818,346	42,648,346
Common stock, shares outstanding (in shares)	42,818,346	42,648,346
Preferred stock, par value (in dollars per share)	$ 0.000001	$ 0.000001
Preferred stock, shares authorized (in shares)	5,000,000	5,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0

Equity - Summary of Nonvested Restricted Stock Unit Activity (Details) - Restricted stock units	3 Months Ended
	Mar. 31, 2023 $ / shares shares
Number of Shares
Non-vested, beginning balance (in shares) \| shares	378,500
Restricted stock units granted (in shares) \| shares	0
Restricted stock units vested (in shares) \| shares	(180,000)
Restricted stock units forfeited (in shares) \| shares	(151,250)
Non-vested, ending balance (in shares) \| shares	47,250
Weighted Average Grant Date Fair Value
Non-vested, beginning balance (in dollars per share) \| $ / shares	$ 4.22
Restricted stock units granted (in dollars per share) \| $ / shares	0
Restricted stock units vested (in dollars per share) \| $ / shares	4.18
Restricted stock units forfeited (in dollars per share) \| $ / shares	4.10
Non-vested, ending balance (in dollars per share) \| $ / shares	$ 4.75

Investments (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Cash equivalents:
Amortized Cost	$ 35,494	$ 37,887
Short-term investments:
Amortized Cost	83,004	95,758
Gross Unrealized Gains	18	6
Gross Unrealized Losses	0	(27)
U.S. treasury securities	83,022	95,737
U.S. treasury securities - due within 3 months
Short-term investments:
Amortized Cost	47,925	58,518
Gross Unrealized Gains	17	6
Gross Unrealized Losses	0	(27)
U.S. treasury securities	47,942	58,497
Money market funds
Cash equivalents:
Amortized Cost	32,084	33,767
Fair Value	32,084	33,767
U.S. treasury securities - due within 3 months
Cash equivalents:
Amortized Cost	2,995	3,473
Fair Value	2,996	$ 3,473
Short-term investments:
Gross Unrealized Gains	$ 1

Equity (Tables)

3 Months Ended

Mar. 31, 2023

Equity [Abstract]

Summary of Stock-based Compensation Expense

Stock-based compensation expense is classified in the condensed statements of operations and comprehensive income (loss) as follows:


(in thousands)	Three Months Ended March 31,
	2023		2022
Research and development expenses	$	256	$	1,264
General and administrative expenses	935		1,182
Total stock-based compensation expense	$	1,191	$	2,446

Schedule of Weighted Average Assumptions

The fair values of stock options granted are estimated using the Black-Scholes option pricing model with the following weighted average assumptions:


	Three Months Ended March 31,
	2023		2022
Expected volatility	85.95	%	83.18	%
Expected dividends	0	%	0	%
Expected terms (years)	6.04		6.07
Risk free rate	3.46	%	1.95	%

Schedule of Stock Option Activity

A summary of the Company’s stock option activity and related information for the three months ended March 31, 2023 is as follows:


	Number of Shares	Weighted Average Exercise Price		Weighted Average Remaining Contractual Life (in Years)	Aggregate Intrinsic Value (in Thousands)
Outstanding at December 31, 2022	8,514,381	$	4.89	8.32	$	—
Options granted	110,500	$	0.59
Options exercised	—	$	—
Options cancelled/forfeited	(3,302,276)	$	4.86
Outstanding at March 31, 2023	5,322,605	$	4.83	4.58	$	3
Exercisable as of March 31, 2023	4,195,975	$	5.41	3.41	$	—

Summary of RSU Activity

A summary of the Company’s RSU activity and related information for the three months ended March 31, 2023 is as follows:


	Number of Shares	Weighted Average Grant Date Fair Value
Non-vested at December 31, 2022	378,500	$	4.22
Restricted stock units granted	—	$	—
Restricted stock units vested	(180,000)	$	4.18
Restricted stock units forfeited	(151,250)	$	4.10
Non-vested at March 31, 2023	47,250	$	4.75

Leases	3 Months Ended
Leases	Mar. 31, 2023
Leases [Abstract]
Leases	Leases The Company enters into lease arrangements for its facilities as well as certain equipment, classified either as operating or finance leases. The Company has an operating lease agreement, as amended by the execution of two subsequent amendments, for approximately 33,300 square feet of office space in Seattle, Washington for the Company’s principal executive offices, a laboratory for research and development, and related uses. The lease commenced on January 15, 2020 and expires on February 1, 2029, with the option to extend the lease for two five-year terms. The lease provides for a tenant improvement allowance of up to $9.5 million, which has been fully utilized. The Company has an operating lease agreement for approximately 6,272 square feet of office space in Seattle, Washington, for additional office and laboratory space for research and development and related uses. In March 2021, the Company executed an amendment to this lease pursuant to which the contractual lease term was extended through September 30, 2026, unless terminated earlier, with the option to extend the lease for an additional 28-month term. In December 2022, the Company entered into an agreement to sublease this office and laboratory space in Seattle, Washington to an unrelated third party. Pursuant to the terms of the sublease, the Company is entitled to receive up to $0.5 million in base lease payments. The term of the sublease is through August 31, 2023, with an option by the sublessee to extend such term through November 30, 2023. As of March 31, 2023, and December 31, 2022, the Company’s operating lease right-of-use assets were $9.4 million and $9.7 million, respectively. As of March 31, 2023, and December 31, 2022, the Company’s finance lease right-of-use assets, included within property and equipment on the condensed balance sheets, were $0.1 million and $0.5 million, respectively.
Leases	Leases The Company enters into lease arrangements for its facilities as well as certain equipment, classified either as operating or finance leases. The Company has an operating lease agreement, as amended by the execution of two subsequent amendments, for approximately 33,300 square feet of office space in Seattle, Washington for the Company’s principal executive offices, a laboratory for research and development, and related uses. The lease commenced on January 15, 2020 and expires on February 1, 2029, with the option to extend the lease for two five-year terms. The lease provides for a tenant improvement allowance of up to $9.5 million, which has been fully utilized. The Company has an operating lease agreement for approximately 6,272 square feet of office space in Seattle, Washington, for additional office and laboratory space for research and development and related uses. In March 2021, the Company executed an amendment to this lease pursuant to which the contractual lease term was extended through September 30, 2026, unless terminated earlier, with the option to extend the lease for an additional 28-month term. In December 2022, the Company entered into an agreement to sublease this office and laboratory space in Seattle, Washington to an unrelated third party. Pursuant to the terms of the sublease, the Company is entitled to receive up to $0.5 million in base lease payments. The term of the sublease is through August 31, 2023, with an option by the sublessee to extend such term through November 30, 2023. As of March 31, 2023, and December 31, 2022, the Company’s operating lease right-of-use assets were $9.4 million and $9.7 million, respectively. As of March 31, 2023, and December 31, 2022, the Company’s finance lease right-of-use assets, included within property and equipment on the condensed balance sheets, were $0.1 million and $0.5 million, respectively.

Summary of significant accounting policies - Additional Information (Details) - USD ($)	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Lessee, Lease, Description [Line Items]
Impairment of property and equipment	$ 3,418,000	$ 0
Allowance for credit loss	0
Fair value, investments, unrealized loss	$ 4,000,000
Expected dividends	0.00%	0.00%
Minimum
Lessee, Lease, Description [Line Items]
Property and equipment, useful life	3 years
Maximum
Lessee, Lease, Description [Line Items]
Property and equipment, useful life	7 years
Fair Value, Recurring \| U.S. treasury securities - due within 3 months
Lessee, Lease, Description [Line Items]
U.S. treasury securities	$ 50,920,000		$ 61,970,000
Prefunded Warrants
Lessee, Lease, Description [Line Items]
Outstanding pre-funded warrants (in shares)	12,663,010	12,663,010
Money market funds
Lessee, Lease, Description [Line Items]
Money market funds	$ 32,084,000		33,767,000
Money market funds \| Fair Value, Recurring
Lessee, Lease, Description [Line Items]
Money market funds	$ 32,084,000		$ 33,767,000
Office space \| Maximum
Lessee, Lease, Description [Line Items]
Lease term	12 months

Equity - Schedule of Stock Options Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Number of Shares
Outstanding, beginning balance (in shares)	8,514,381
Options granted (in shares)	110,500
Options exercised (in shares)	0	(36,500)
Options cancelled/ forfeited (in shares)	(3,302,276)
Outstanding, ending balance (in shares)	5,322,605		8,514,381
Weighted Average Exercise Price
Outstanding, beginning balance (in dollars per share)	$ 4.89
Options granted (in dollars per share)	0.59
Options exercised (in dollars per share)	0
Options cancelled/forfeited (in dollars per share)	4.86
Outstanding, ending balance (in dollars per share)	$ 4.83		$ 4.89
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Outstanding, Weighted Average Remaining Contractual Life (in Years)	4 years 6 months 29 days		8 years 3 months 25 days
Outstanding, Aggregate Intrinsic Value (in Thousands)	$ 3		$ 0
Exercisable, Number of Shares (in shares)	4,195,975
Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 5.41
Exercisable, Weighted Average Remaining Contractual Life (in Years)	3 years 4 months 28 days
Exercisable, Aggregate Intrinsic Value (in Thousands)	$ 0

Restructurings and impairment charges (Details) - USD ($) $ in Thousands		3 Months Ended			13 Months Ended
	Nov. 14, 2022	Mar. 31, 2023	Dec. 31, 2022	Mar. 31, 2022	Mar. 31, 2024	Mar. 06, 2023
Restructuring Cost and Reserve [Line Items]
Restructuring charges		$ 1,967
Amounts Paid		(834)
Accrued at period end		2,174	$ 1,041
Impairment of property and equipment		3,418		$ 0
November 2022 Reductions
Restructuring Cost and Reserve [Line Items]
Restructing number of positions eliminated, percentage	40.00%
Restructuring costs		1,700
Restructuring charges		327	1,400
Amounts Paid		(490)
Accrued at period end		878	1,041
March 2023 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Restructuring costs						$ 1,800
Restructuring and Related Cost, Expected Cost Remaining		200
Restructuring charges		1,640
Amounts Paid		(344)
Accrued at period end		1,296	$ 0
March 2023 Restructuring Plan \| Forecast
Restructuring Cost and Reserve [Line Items]
Restructing number of positions eliminated, percentage					70.00%
March 2023 Restructuring Plan \| General and administrative expenses
Restructuring Cost and Reserve [Line Items]
Restructuring charges		600
March 2023 Restructuring Plan \| Research and development expenses
Restructuring Cost and Reserve [Line Items]
Restructuring charges		$ 1,000

Equity

3 Months Ended

Mar. 31, 2023

Equity [Abstract]

Equity

(a)Common stock and pre-funded warrants

The Company is authorized to issue 100,000,000 shares of common stock with a par value of $0.000001 as of March 31, 2023 and December 31, 2022. As of March 31, 2023 and December 31, 2022, the total number of shares of common stock issued and outstanding was 42,818,346 and 42,648,346, respectively.

As of March 31, 2023, the Company had pre-funded warrants outstanding to purchase an aggregate of 12,663,010 shares of common stock. The pre-funded warrants are exercisable at any time for an exercise price of $0.000001, except that the pre-funded warrants cannot be exercised by the holders if, after giving effect thereto, the holders would beneficially own more than 9.99% of the outstanding common stock, subject to certain exceptions. However, any holder may increase or decrease such percentage to any other percentage (not in excess of 19.99%) upon at least 61 days’ prior notice from the holder to the Company. The holders of the pre-funded warrants will not have the right to vote on any matter except to the extent required by Delaware law.

On November 4, 2021, the Company entered into an ATM or “at-the-market” Equity Offering Sales Agreement (the “Sales Agreement”) with BofA Securities, Inc., as agent (“BofA”), pursuant to which the Company may offer and sell, from time to time through BofA, shares of the Company’s common stock, having an aggregate offering price of up to $40.0 million. The offer and sale of the shares will be made pursuant to a shelf registration statement on Form S-3 and the related prospectus filed on December 11, 2020, and declared effective by the SEC on December 21, 2020, as supplemented by a prospectus supplement dated November 4, 2021. The Company has no obligation to sell any such shares under the Sales Agreement. Through March 31, 2023, no sales of common stock have been made pursuant to the Sales Agreement. As of March 20, 2023, we are subject to limitations on the amount of funds we can raise by selling shares of our common stock using our Form S-3, including sales under this ATM facility, to one-third of the aggregate market value of the shares of our common stock held by non-affiliates, or public float, due to the so-called "baby shelf" requirements set forth in the SEC general instructions of Form S-3. These restrictions will remain in place until such time as our public float exceeds $75 million.

(b)Stock-based compensation expense

Stock-based compensation expense is classified in the condensed statements of operations and comprehensive income (loss) as follows:


(in thousands)	Three Months Ended March 31,
	2023		2022
Research and development expenses	$	256	$	1,264
General and administrative expenses	935		1,182
Total stock-based compensation expense	$	1,191	$	2,446

Total unrecognized compensation expense for all stock-based compensation plans was $2.0 million as of March 31, 2023. This expense is expected to be recognized over a weighted average remaining vesting period of 2.05 years.

The fair values of stock options granted are estimated using the Black-Scholes option pricing model with the following weighted average assumptions:


	Three Months Ended March 31,
	2023		2022
Expected volatility	85.95	%	83.18	%
Expected dividends	0	%	0	%
Expected terms (years)	6.04		6.07
Risk free rate	3.46	%	1.95	%

(c)Stock options

A summary of the Company’s stock option activity and related information for the three months ended March 31, 2023 is as follows:


	Number of Shares	Weighted Average Exercise Price		Weighted Average Remaining Contractual Life (in Years)	Aggregate Intrinsic Value (in Thousands)
Outstanding at December 31, 2022	8,514,381	$	4.89	8.32	$	—
Options granted	110,500	$	0.59
Options exercised	—	$	—
Options cancelled/forfeited	(3,302,276)	$	4.86
Outstanding at March 31, 2023	5,322,605	$	4.83	4.58	$	3
Exercisable as of March 31, 2023	4,195,975	$	5.41	3.41	$	—

During the three months ended March 31, 2023, no shares of common stock were issued upon exercise of options. During the three months ended March 31, 2022, 36,500 shares of common stock were issued upon exercise of options with an aggregate intrinsic value of $0.1 million. The weighted-average grant date fair value of options granted during the three months ended March 31, 2023 and March 31, 2022 was $0.43 and $1.75 per share, respectively.

(d)Restricted stock units

A summary of the Company’s RSU activity and related information for the three months ended March 31, 2023 is as follows:


	Number of Shares	Weighted Average Grant Date Fair Value
Non-vested at December 31, 2022	378,500	$	4.22
Restricted stock units granted	—	$	—
Restricted stock units vested	(180,000)	$	4.18
Restricted stock units forfeited	(151,250)	$	4.10
Non-vested at March 31, 2023	47,250	$	4.75

During the quarter ended March 31, 2023, 180,000 RSUs vested. As of March 31, 2023, 170,000 shares issued upon the vesting of these RSUs are issued and outstanding. The remaining 10,000 shares relate to a RSU that vested on March 31, 2023, and such shares are not issued and outstanding as of March 31, 2023.

(e)Employee stock purchase plan

The Company’s 2020 ESPP was adopted by the Company’s Board of Directors in March 2020 and approved by the Company’s stockholders in May 2020. A total of 759,936 shares of common stock have been reserved for issuance under the 2020 ESPP.

Subject to share and dollar limits as described in the plan, the 2020 ESPP allows eligible employees to contribute, through payroll deductions, up to 15% of their earnings for the purchase of shares of the Company’s common stock at the lower of 85% of the closing price of the Company’s common stock on the first trading day of the offering period or 85% of the closing price of the Company’s common stock on the last trading day of the offering period. There are two six-month offering periods during each fiscal year, ending on May 15 and November 15.

As of March 31, 2023 and December 31, 2022, employee contributions included in accounts payable and accrued liabilities in the accompanying condensed balance sheet were immaterial.

- 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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-URI https://asc.fasb.org/topic&trid=2208762

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126973232&loc=SL123496158-112644

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 13
-URI https://asc.fasb.org/extlink&oid=126973232&loc=SL123496158-112644

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 14
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=126973232&loc=SL123496171-112644

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 14
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126973232&loc=SL123496171-112644

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI https://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 18
-Subparagraph (d)
-URI https://asc.fasb.org/extlink&oid=126973232&loc=SL123496189-112644

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (g)
-URI https://asc.fasb.org/extlink&oid=126973232&loc=SL123496158-112644

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 18
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126973232&loc=SL123496189-112644

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (h)
-URI https://asc.fasb.org/extlink&oid=126973232&loc=SL123496158-112644

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 14
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126973232&loc=SL123496171-112644

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 18
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126973232&loc=SL123496189-112644

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 16
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126973232&loc=SL123496180-112644

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (i)
-URI https://asc.fasb.org/extlink&oid=126973232&loc=SL123496158-112644

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(e)(1))
-URI https://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126731327&loc=SL126733271-114008

+ Details

Cash, cash equivalents, and restricted cash

3 Months Ended

Mar. 31, 2023

Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents [Abstract]

Cash, cash equivalents, and restricted cash

The Company considers all highly liquid investments with an original contractual maturity or a remaining maturity of three months or less at the date of purchase to be cash equivalents. Cash equivalents consist of money market funds and U.S. treasury securities as of March 31, 2023 and December 31, 2022.


(in thousands)	March 31, 2023		December 31, 2022
Cash and cash equivalents	$	35,494	$	37,887
Restricted cash	878		878
Total cash, cash equivalents, and restricted cash	$	36,372	$	38,765

Restricted cash, included in other non-current assets in the condensed balance sheets, includes $0.9 million in cash deposits the Company maintains with its bank as collateral for the irrevocable letters of credit related to its lease obligations.

Leases - Additional Information (Details) $ in Thousands	1 Months Ended	3 Months Ended
Leases - Additional Information (Details) $ in Thousands	Dec. 31, 2022 USD ($)	Mar. 31, 2023 USD ($) ft² option	Mar. 31, 2022 USD ($)
Lessee, Lease, Description [Line Items]
Increase in lease liability		$ (326)	$ (275)
Sublease, base lease payments	$ 500
Operating lease right-of-use assets	9,715	9,430
Finance lease right-of-use assets	$ 500	100
Office space, principal executive offices and laboratory
Lessee, Lease, Description [Line Items]
Tenant improvements (up to)		$ 9,500
Washington \| Office space, principal executive offices and laboratory
Lessee, Lease, Description [Line Items]
Square feet of office space leased \| ft²		33,300
Number of option to extend leases \| option		2
Lease agreement extended period		5 years
Washington \| Office space, additional offices and laboratory
Lessee, Lease, Description [Line Items]
Square feet of office space leased \| ft²		6,272
Lease agreement extended period		28 months

Net loss per share (Tables)

3 Months Ended

Mar. 31, 2023

Earnings Per Share [Abstract]

Schedule of Potentially Dilutive Shares From Diluted Net Loss Per Share

The Company excluded the following potentially dilutive shares from diluted net loss per share as the effect would have been anti-dilutive for all periods presented:


	Three Months Ended March 31,
	2023	2022
Outstanding stock options	5,322,605	8,297,921
Restricted stock units	47,250	710,000
Shares issuable under 2020 ESPP	13,347	45,261
	5,383,202	9,053,182