0001564590-21-026569 | 10-Q | XBRL Viewer

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Organization and Basis of Presentation - Additional Information (Details) $ / shares in Units, $ in Thousands			3 Months Ended
	May 05, 2020 USD ($) $ / shares shares	Mar. 11, 2020 Patient	Mar. 31, 2021 USD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2020 USD ($)
Organization And Basis Of Presentation [Line Items]
Net losses			$ 7,802	$ 4,232
Accumulated deficit			(157,686)		$ (149,884)
Cash and cash equivalents			$ 66,105		$ 74,593
Number of patients \| Patient		67
Common Stock
Organization And Basis Of Presentation [Line Items]
Gross proceeds from initial public offering	$ 64,400
Net proceeds from initial public offering	$ 57,300
IPO \| Common Stock
Organization And Basis Of Presentation [Line Items]
Issuance of common stock from initial public offering, net of issuance costs, Shares \| shares	4,025,000
Shares issued and sold, public offering price \| $ / shares	$ 16.00
Exercise of Underwriters' Option \| Common Stock
Organization And Basis Of Presentation [Line Items]
Issuance of common stock from initial public offering, net of issuance costs, Shares \| shares	525,000

Stock-Based Compensation Expense (Tables)

3 Months Ended

Mar. 31, 2021

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Schedule of Stock-Based Compensation Expense

Stock-based compensation expense included in the Company’s condensed consolidated statements of operations and comprehensive loss was as follows (in thousands):

	Three Months Ended March 31,
	2021		2020
Research and development	$	142	$	40
General and administrative		457		94
Total	$	599	$	134

Schedule of Fair Value of Stock Option Estimated on Date of Grant Using Black-Scholes Option-Pricing Model

The fair value of each stock option granted to employees, directors and non-employees was estimated on the date of grant using the Black-Scholes option-pricing model, with the following weighted-average assumptions:

	Three Months Ended March 31,
	2021			2020
Risk-free interest rate		0.6	%		1.5	%
Expected dividend yield		—	%		—	%
Expected term (in years)		6.0			6.0
Expected volatility		85.4	%		78.0	%

Summary of Stock Option Activity Under Plans

A summary of the stock option activity under the Plans for the three months ended March 31, 2021 was as follows:

	Shares			Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Life (in years)		Aggregate Intrinsic Value (in thousands)
Outstanding December 31, 2020		1,428,886		$	10.41		7.7	$	5,165
Granted		365,700			10.75
Exercised		(30,391	)		8.63
Cancelled		(1,590	)		11.70
Outstanding at March 31, 2021		1,762,605		$	10.51		8.1	$	5,540
Exercisable at March 31, 2021		665,936		$	9.39		6.3	$	3,349
Vested and expected to vest at March 31, 2021		1,762,605		$	10.51		8.1	$	5,540

Leases - Additional Information (Details) $ in Thousands	1 Months Ended	3 Months Ended
Leases - Additional Information (Details) $ in Thousands	Nov. 30, 2017 USD ($)	Mar. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Aug. 31, 2007 ft²
Lessee Lease Description [Line Items]
Initial base rent	$ 1,000
Restricted cash		$ 329	$ 329
Extended lease term	2023-04
Office and Laboratory
Lessee Lease Description [Line Items]
Area of property \| ft²				22,343
Office Equipment
Lessee Lease Description [Line Items]
Lease initiation date		Apr. 30, 2020
Lease expiration date		Jun. 30, 2024
Certificate of Deposits
Lessee Lease Description [Line Items]
Restricted cash	$ 300
Letter of Credit
Lessee Lease Description [Line Items]
Secured debt obligations	$ 300

Summary of Significant Accounting Policies (Tables)

3 Months Ended

Mar. 31, 2021

Accounting Policies [Abstract]

Summary of Basic and Diluted Net Loss per Share Attributable to Common Stockholders

Basic and diluted net loss per share attributable to common stockholders was calculated as follows (in thousands, except share and per share data):

	Three Months Ended March 31,
	2021			2020
Numerator:
Net loss	$	(7,802	)	$	(4,232	)
Accretion of redeemable convertible preferred stock		—			(85	)
Net loss attributable to common stockholders	$	(7,802	)	$	(4,317	)
Denominator:
Weighted-average common shares—basic and diluted		12,945,546			230,860
Net loss per share attributable to common stockholders—basic and diluted	$	(0.60	)	$	(18.70	)

Summary of Potentially Dilutive Securities Excluded from Calculation of Diluted Net Loss per Share

The following table sets forth the potentially dilutive securities that have been excluded from the calculation of diluted net loss per share because to include them would be anti-dilutive (in common stock equivalent shares retroactively adjusted):

	Three Months Ended March 31,
	2021		2020
Series A-1 redeemable convertible preferred stock		—		986,466
Series A-2 redeemable convertible preferred stock		—		773,712
Series A-3 redeemable convertible preferred stock		—		872,031
Series A-4 redeemable convertible preferred stock		—		579,993
Series B redeemable convertible preferred stock		—		2,852,177
Series C redeemable convertible preferred stock		—		2,270,869
Warrants to purchase common stock		—		681,256
Stock options		1,762,605		901,678
Total		1,762,605		9,918,182

Stock-Based Compensation Expense - Schedule of Fair Value of Stock Option Estimated on Date of Grant Using Black-Scholes Option-Pricing Model (Details)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Risk-free interest rate	0.60%	1.50%
Expected term (in years)	6 years	6 years
Expected volatility	85.40%	78.00%

Income Taxes

3 Months Ended

Mar. 31, 2021

Income Tax Disclosure [Abstract]

Income Taxes

8. Income Taxes

During the three months ended March 31, 2021 and 2020, the Company recorded a full valuation allowance on federal and state deferred tax assets since management does not forecast the Company to be in a taxable position in the near future.

- Definition

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

+ References + Details

Property and Equipment - Additional Information (Details) - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Property Plant And Equipment [Abstract]
Depreciation expense	$ 70,000	$ 8,000

Accrued Expenses and Other Current Liabilities

3 Months Ended

Mar. 31, 2021

Payables And Accruals [Abstract]

Accrued Expenses and Other Current Liabilities

5. Accrued Expenses and Other Current Liabilities

Accrued expenses and other current liabilities consist of the following (in thousands):

	March 31,		December 31,
	2021		2020
Payroll and employee related expenses	$	1,213	$	1,892
Third-party research and development expenses		195		381
Professional and consulting fees		523		555
Other		63		149
Total accrued expenses and other current liabilities	$	1,994	$	2,977

Preferred and Common Stock - Additional Information (Details) $ / shares in Units, $ in Millions		3 Months Ended
	May 05, 2020 USD ($) $ / shares shares	Mar. 31, 2021 USD ($) Vote $ / shares shares	Dec. 31, 2020 $ / shares shares	May 31, 2020 shares
Class Of Stock [Line Items]
Common stock shares authorized	200,000,000	200,000,000	200,000,000
Common stock par value \| $ / shares	$ 0.001	$ 0.001	$ 0.001
Preferred Stock, Shares Authorized	10,000,000
Preferred Stock, Par or Stated Value Per Share \| $ / shares	$ 0.001
Common stock, voting rights		The holders of common stock are entitled to one vote for each share held.
Number of common stock voting rights \| Vote		1
Reverse stock split of issued and outstanding common stock		one-for-34.483
Common stock shares issued		12,962,768	12,932,377
IPO
Class Of Stock [Line Items]
Common stock shares issued				313,794
Common Stock
Class Of Stock [Line Items]
Gross proceeds from initial public offering \| $	$ 64.4
Net proceeds from initial public offering \| $	$ 57.3
Preferred stock converted into common stock	8,335,248
Number of warrants issued to purchase common stock	313,794	681,256
Warrants exercise price, per share \| $ / shares		$ 8.63
Common Stock \| Director
Class Of Stock [Line Items]
Vested share of common stock	19,661
Common Stock \| IPO
Class Of Stock [Line Items]
Issuance of common stock from initial public offering, net of issuance costs, Shares	4,025,000
Shares issued and sold, public offering price \| $ / shares	$ 16.00
Common Stock \| Exercise of Underwriters' Option
Class Of Stock [Line Items]
Issuance of common stock from initial public offering, net of issuance costs, Shares	525,000
Warrants \| Series C Redeemable Convertible Preferred Stock
Class Of Stock [Line Items]
Net proceeds from issuance of preferred stock allocated to warrants \| $		$ 0.7

Stock-Based Compensation Expense - Schedule of Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 599	$ 134
Research and Development
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	142	40
General and Administrative
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 457	$ 94

Fair Value Measurements - Additional Information (Details) - USD ($)	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020
Fair Value Disclosures [Abstract]
Financial assets, fair value	$ 0	$ 0
Financial liabilities, fair value	$ 0	$ 0
Alternative investment, change in valuation technique	false		false

Property and Equipment

3 Months Ended

Mar. 31, 2021

Property Plant And Equipment [Abstract]

Property and Equipment

4. Property and Equipment

Property and equipment consist of the following at March 31, 2021 and December 31, 2020 (in thousands):

	March 31,			December 31,
	2021			2020
Property and equipment:
Laboratory equipment	$	3,539		$	3,277
Computer software and equipment		668			650
Office furniture and fixtures		301			301
Leasehold improvements		317			317
Construction in progress		1,291			498
	$	6,116		$	5,043
Accumulated depreciation		(2,948	)		(2,878	)
Property and equipment, net	$	3,168		$	2,165

The Company recognized approximately $70,000 and $8,000 of depreciation expense for the three months ended March 31, 2021 and 2020, respectively.

Leases (Tables)

3 Months Ended

Mar. 31, 2021

Leases [Abstract]

Components of Lease Cost

The components of lease cost recorded in the Company’s condensed consolidated financial statements were as follows (in thousands):

	Three Months Ended March 31,
	2021		2020
Lease Cost:
Operating lease cost	$	264	$	263
Variable lease cost		119		193
Total lease cost	$	383	$	456

Summary of Weighted-Average Remaining Lease Term and Discount Rate Related to Operating Leases

The weighted-average remaining lease term and discount rate related to the Company’s operating leases were as follows:

	As of March 31, 2021
Weighted-average remaining lease term (in years)		2.1
Weighted-average discount rate		5.5	%

Summary of Maturity of Operating Lease Liabilities

Maturity of the Company’s operating lease liabilities in accordance with ASC 842 as of March 31, 2021 were as follows (in thousands):

Year ending December 31,
Remainder of 2021	$	827
2022		1,127
2023		382
2024		2
Total maturities		2,338
Less: Amount representing interest		(135	)
Present value of operating lease liability		2,203
Less: Current portion of operating lease liability		(1,007	)
Total operating lease liability, net of current portion	$	1,196

Leases - Schedule of Components of Lease Cost (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Lease Cost:
Operating lease cost	$ 264	$ 263
Variable lease cost	119	193
Total lease cost	$ 383	$ 456

Condensed Consolidated Balance Sheets (Parenthetical) (unaudited) - $ / shares	Mar. 31, 2021	Dec. 31, 2020
Statement Of Financial Position [Abstract]
Common stock par value	$ 0.001	$ 0.001
Common stock shares authorized	200,000,000	200,000,000
Common stock shares issued	12,962,768	12,932,377
Common stock shares outstanding	12,962,768	12,932,377

Leases - Summary of Weighted-Average Remaining Lease Term and Discount Rate Related to Operating Leases (Details)	Mar. 31, 2021
Leases [Abstract]
Weighted-average remaining lease term (in years)	2 years 1 month 6 days
Weighted-average discount rate	5.50%

Stock-Based Compensation Expense - Additional Information (Details) - USD ($)	1 Months Ended			3 Months Ended
	Apr. 30, 2020	Jan. 31, 2020	Feb. 29, 2016	Mar. 31, 2021	Mar. 31, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares granted				365,700
Shares of common stock reserved for future issuances				3,590,218
Stock-based compensation				$ 599,000	$ 134,000
Weighted-average fair value of options granted to employees, directors and consultants				$ 7.65	$ 5.84
Aggregate intrinsic value of stock options exercised				$ 200,000	$ 0
Unrecognized stock-based compensation expense relating to unvested stock options				$ 8,400,000
Unvested stock options expected to be recognized over a weighted-average period				3 years 2 months 12 days
Milestone-based Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation				$ 0	$ 0
Revenue-based Milestone
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized stock-based compensation expense relating to unvested stock options				$ 36,000
Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period				4 years
Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock option expiration period				10 years
2005 and 2016 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares granted			0
2020 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares of common stock reserved for future issuances	2,100,000
Maximum number of common shares issued	8,800,000
Percentage of common shares increase automatically in each year	4.00%
Number of shares available for future grant				1,612,952
Increase in Shares available for grant		517,295
2020 ESPP
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares of common stock reserved for future issuances	150,000
Maximum number of common shares issued	987,500
Annual increase in number of shares available for issuance as percentage of outstanding shares common stock on final day of immediately preceding fiscal year	0.50%
Purchase price of shares as percentage lower of fair market value of common stock	85.00%

Preferred and Common Stock (Tables)

3 Months Ended

Mar. 31, 2021

Equity [Abstract]

Schedule of Common Stock Reserved for Future Issuances

The Company has reserved for future issuances the following shares of common stock as of March 31, 2021:

	As of March 31, 2021
Stock options		3,375,557
Employee stock purchase plan		214,661
Total		3,590,218

Condensed Consolidated Statements of Redeemable Convertible Preferred Stock and Stockholders' Equity (Deficit) (Parenthetical) (unaudited) $ in Thousands	3 Months Ended
	Mar. 31, 2020 USD ($)
Series C Redeemable Convertible Preferred Stock
Temporary equity, issuance costs	$ 201

Condensed Consolidated Statements of Operations and Comprehensive Loss (unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Operating expenses:
Research and development	$ 4,770	$ 2,964
General and administrative	3,061	1,284
Total operating expenses	7,831	4,248
Loss from operations	(7,831)	(4,248)
Other income:
Interest income	29	16
Total other income	29	16
Net loss	(7,802)	(4,232)
Comprehensive loss	$ (7,802)	$ (4,232)
Net loss per share attributable to common stockholders—basic and diluted	$ (0.60)	$ (18.70)
Weighted-average common shares outstanding—basic and diluted	12,945,546	230,860

Condensed Consolidated Balance Sheets (unaudited) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 66,105	$ 74,593
Prepaid expenses and other current assets	1,246	1,324
Total current assets	67,351	75,917
Property and equipment, net	3,168	2,165
Operating lease right-of-use assets	2,069	2,301
Restricted cash	329	329
Other assets		118
Total assets	72,917	80,830
Current liabilities:
Accounts payable	1,169	922
Accrued expenses and other current liabilities	1,994	2,977
Operating lease liabilities	1,007	985
Total current liabilities	4,170	4,884
Operating lease liabilities, net of current portion	1,196	1,454
Total liabilities	5,366	6,338
Commitments and contingencies (Note 9)
Stockholders’ equity:
Common stock, $0.001 par value; 200,000,000 shares authorized at March 31, 2021 and December 31, 2020; 12,962,768 and 12,932,377 shares issued and outstanding at March 31, 2021 and December 31, 2020, respectively	13	13
Additional paid-in capital	225,224	224,363
Accumulated deficit	(157,686)	(149,884)
Total stockholders’ equity	67,551	74,492
Total liabilities and stockholders’ equity	$ 72,917	$ 80,830

Stock-Based Compensation Expense

3 Months Ended

Mar. 31, 2021

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Stock-Based Compensation Expense

7. Stock-Based Compensation Expense

The Company adopted the 2016 Equity Incentive Plan (“2016 Plan”) in February 2016 and amended it in June 2017 and June 2018. Upon adoption of the 2016 Plan, no further grants were made under the 2005 Equity Incentive Plan (“2005 Plan”).

In April 2020, the Company’s Board of Directors adopted the Company’s 2020 Incentive Award Plan (“2020 Plan”, and together with the 2016 Plan and 2005 Plan, the “Plans”), and upon effectiveness of the 2020 Plan, the Company ceased granting equity-based awards under the 2016 Plan. The 2020 Plan provides for grant of incentive stock options and nonqualified stock options, stock appreciation rights, restricted stock, dividend equivalents, restricted stock units, performance awards and other share and cash-based awards to employees and consultants and members of the Board of Directors of the Company and its subsidiaries.

The initial number of shares of the Company’s common stock that may be issued under the 2020 Plan is 2,100,000 shares plus the number of shares of the Company’s common stock underlying outstanding awards under the 2005 Plan and 2016 Plan as of the effective date of the 2020 Plan that expire, lapse or are terminated, exchanged for cash, surrendered, repurchased, canceled or forfeited following the effective date of the 2020 Plan. The number of shares available under the 2020 Plan will automatically increase on January 1st of each year from 2021 to 2030 by the lesser of (i) 4% of the number of shares of common stock outstanding on the final day of the immediately preceding calendar year and (ii) a smaller number of shares determined by the Company’s Board of Directors. However, no more than 8,800,000 shares may be issued under the 2020 Plan pursuant to the exercise of incentive stock options. On January 1, 2020, the shares available for grant under the 2020 Plan was automatically increased by 517,295. As of March 31, 2021, the Company had 1,612,952 shares available for issuance under the 2020 Plan.

All stock option grants are nonqualified stock options except option grants to employees and officers intended to qualify as incentive stock options under the Internal Revenue Code of 1986, as amended. Stock options may not be granted at less than the fair market value of the Company’s common stock on the date of grant. Vesting periods of awards are determined by the Board of Directors or its compensation committee. Vesting periods of awards granted to date range from vesting upon grant to vesting over a four-year period. Vesting conditions are generally based on continued service. Additionally, the Company has granted certain awards which vest upon the achievement of certain financing and revenue milestones. Stock options granted under the Plans expire no more than 10 years from the date of grant.

Stock-based compensation expense included in the Company’s condensed consolidated statements of operations and comprehensive loss was as follows (in thousands):

	Three Months Ended March 31,
	2021		2020
Research and development	$	142	$	40
General and administrative		457		94
Total	$	599	$	134

The Company did not record any stock-based compensation associated with milestone-based awards in the three months ended March 31, 2021 and 2020.

	Three Months Ended March 31,
	2021			2020
Risk-free interest rate		0.6	%		1.5	%
Expected dividend yield		—	%		—	%
Expected term (in years)		6.0			6.0
Expected volatility		85.4	%		78.0	%

A summary of the stock option activity under the Plans for the three months ended March 31, 2021 was as follows:

	Shares			Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Life (in years)		Aggregate Intrinsic Value (in thousands)
Outstanding December 31, 2020		1,428,886		$	10.41		7.7	$	5,165
Granted		365,700			10.75
Exercised		(30,391	)		8.63
Cancelled		(1,590	)		11.70
Outstanding at March 31, 2021		1,762,605		$	10.51		8.1	$	5,540
Exercisable at March 31, 2021		665,936		$	9.39		6.3	$	3,349
Vested and expected to vest at March 31, 2021		1,762,605		$	10.51		8.1	$	5,540

The weighted-average fair value of options granted to employees, directors and non-employees during the three months ended March 31, 2021 and 2020 was $7.65 and $5.84, respectively.

The aggregate intrinsic value of stock options is calculated as the difference between the exercise price of the stock options and the fair value of the Company’s common stock for those stock options that had exercise prices lower than the fair value of the Company’s common stock. The aggregate intrinsic value of stock options exercised during the three months ended March 31, 2021 and 2020 was approximately $0.2 million and $0, respectively.

As of March 31, 2021, total unrecognized stock-based compensation expense relating to unvested stock options was approximately $8.4 million. This amount is expected to be recognized over a weighted-average period of 3.2 years. Additionally, as of March 31, 2021, there was approximately $36,000 of unrecognized stock-based compensation related to a stock option award related to the achievement of a revenue-based milestone. As the Company believes the achievement of the revenue-based milestone is currently not probable, it has not recorded any stock-based compensation related to this award. The Company will continue to assess the probability of achieving the revenue-based milestone at each reporting period.

2020 Employee Stock Purchase Plan

In April 2020, the Company’s Board of Directors adopted the Company’s 2020 Employee Stock Purchase Plan (“2020 ESPP”). The 2020 ESPP is structured as a qualified employee stock purchase plan under Section 423 of the Internal Revenue Code of 1986, as amended, and is not subject to the provisions of the Employee Retirement Income Security Act of 1974. The Company initially reserved 150,000 shares of common stock for issuance under the 2020 ESPP. In addition, the number of shares available for issuance under the 2020 ESPP will be annually increased on January 1st of each year from 2021 to 2030 by the lesser of (i) 0.5% of the number of shares of common stock outstanding on the final day of the immediately preceding calendar year and (ii) such smaller number of shares as is determined by the Company’s Board of Directors, provided that no more than 987,500 shares of common stock may be issued under the 2020 ESPP. On January 1, 2020, the shares available for grant under the 2020 ESPP was automatically increased by 64,661. The 2020 ESPP permits eligible participants to purchase common stock through payroll deductions of up to a specified percentage of their eligible compensation. On the first trading day of each offering period, each participant will automatically be granted an option to purchase shares of the Company’s common stock. The option will expire at the end of the applicable offering period, and will be exercised at that time to the extent of the payroll deductions accumulated during the offering period, subject to the limits set forth in the 2020 ESPP. The purchase price of the shares, in the absence of a contrary designation, will be 85% of the lower of the fair market value of the Company’s common stock on the first trading day of the offering period or on the purchase date. As of March 31, 2021, no shares have been issued under the 2020 ESPP.

Accrued Expenses and Other Current Liabilities - Schedule of Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Payables And Accruals [Abstract]
Payroll and employee related expenses	$ 1,213	$ 1,892
Third-party research and development expenses	195	381
Professional and consulting fees	523	555
Other	63	149
Total accrued expenses and other current liabilities	$ 1,994	$ 2,977

Summary of Significant Accounting Policies (Policies)

3 Months Ended

Mar. 31, 2021

Accounting Policies [Abstract]

COVID-19 Pandemic and CARES Act

On January 30, 2020, the World Health Organization (“WHO”) announced a global health emergency because of a new strain of coronavirus originating in Wuhan, China (the “COVID-19 outbreak”) and the risks to the international community as the virus subsequently spread globally beyond its point of origin. On March 11, 2020, the WHO classified the COVID-19 outbreak as a pandemic, based on the rapid increase in exposure globally. The COVID-19 pandemic is affecting the United States and global economies and may affect the Company’s operations and those of third parties on which the Company relies, including by causing disruptions in the supply of the Company’s product candidates and the conduct of current and future clinical trials. In addition, the COVID-19 pandemic may affect the operations of the Food and Drug Administration and other health authorities, which could result in delays of reviews and approvals, including with respect to the Company’s product candidates. In light of developments relating to the COVID-19 pandemic, the Company discontinued enrollment at 67 patients in its Phase 2 LANTERN clinical trial and did not enroll patients in the United States. Additionally, while the potential economic impact brought by, and the duration of, the COVID-19 pandemic is difficult to assess or predict, the impact of the COVID-19 pandemic on the global financial markets may reduce the Company’s ability to access capital, which could negatively impact the Company’s short-term and long-term liquidity. The ultimate impact of the COVID-19 pandemic is highly uncertain and subject to change. The Company does not yet know the full extent of potential delays or impacts on its business, financing or clinical trial activities or on healthcare systems or the global economy as a whole. However, these effects could have a material impact on the Company’s liquidity, capital resources, operations and business and those of the third parties on which the Company relies.

On March 27, 2020, President Trump signed into law the “Coronavirus Aid, Relief, and Economic Security (CARES) Act.” The CARES Act, among other things, includes provisions relating to refundable payroll tax credits, deferment of employer side social security payments, net operating loss carryback periods, alternative minimum tax credit refunds, modifications to the net interest deduction limitations, increased limitations on qualified charitable contributions, and technical corrections to tax depreciation methods for qualified improvement property. The Company deferred the employer side social security payments. The CARES Act also appropriated funds for the SBA Paycheck Protection Program loans that are forgivable in certain situations to promote continued employment, as well as Economic Injury Disaster Loans to provide liquidity to small businesses harmed by COVID-19. On December 27, 2020, the Consolidated Appropriations Act, 2021 was signed into law in order to provide further stimulus and support to those affected by the COVID-19 pandemic. The Company has not and does not plan on obtaining funding from such loans. The Company does not believe the CARES Act or the Consolidated Appropriations Act, 2021 will have a material impact on its financial condition, results of operations, or liquidity.

Basis of Presentation

The accompanying condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”). Any reference in these notes to applicable guidance is meant to refer to the authoritative United States generally accepted accounting principles as found in the Accounting Standard Codification (“ASC”) and Accounting Standards Updates (“ASU”) of the Financial Accounting Standards Board (“FASB”).

The condensed consolidated financial statements have been prepared on the same basis as the audited annual financial statements and, in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary for the fair statement of the Company’s financial position as of March 31, 2021 and the results of its operations and its cash flows for the three months ended March 31, 2021 and 2020. The results for the three months ended March 31, 2021 are not necessarily indicative of results to be expected for the year ending December 31, 2021, any other interim periods, or any future year or period. These condensed consolidated financial statements should be read in conjunction with the audited financial statements as of and for the year ended December 31, 2020, and the notes thereto, which are included in the Company’s Annual Report on Form 10-K filed with the Securities and Exchange Commission (“SEC”) on March 9, 2021.

Use of Estimates

The preparation of the Company’s condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, expenses and related disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements and reported amounts of expenses during the reporting period. On an ongoing basis, the Company’s management evaluates its estimates, which include but are not limited to management’s judgments of accrued expenses, fair value of common stock, valuation of share-based awards, warrants to purchase common stock and deferred income taxes. Due to the uncertainty inherent in such estimates, actual results may differ from these estimates.

The Company utilizes significant estimates and assumptions in determining the fair value of its common stock. The Company has utilized various valuation methodologies to estimate the fair value of its common stock. Each valuation methodology includes estimates and assumptions that require the Company’s judgment. These estimates and assumptions include a number of objective and subjective factors, including external market conditions, the prices at which the Company sold shares of preferred stock, the superior rights and preferences of securities senior to the Company’s common stock at the time of, and the likelihood of, achieving a liquidity event, such as an initial public offering or sale. Significant changes to the key assumptions used in the valuations could result in different fair values of common stock at each valuation date.

Restricted Cash

The Company had restricted cash of approximately $0.3 million as of March 31, 2021 and December 31, 2020, which was held in certificates of deposit at the Company’s financial institution to secure the Company’s letter of credit for its facility lease.

Concentrations of Credit Risk and Off-Balance Sheet Risk

Financial instruments that potentially expose the Company to concentrations of credit risk consist primarily of cash and cash equivalents. The Company maintains all its cash and cash equivalents at a single accredited financial institution, in amounts that exceed federally insured limits.

The Company has no significant off-balance sheet risk such as foreign exchange contracts, option contracts, or other foreign exchange hedging arrangements.

Net Loss per Share

The Company has reported losses since inception and has computed basic net loss per share attributable to common stockholders by dividing net loss attributable to common stockholders by the weighted-average number of common shares outstanding for the period, without consideration for potentially dilutive securities. The Company has computed diluted net loss per common share after giving consideration to all potentially dilutive common shares, including options to purchase common stock, warrants to purchase common stock and redeemable convertible preferred stock, outstanding during the period determined using the treasury-stock and if-converted methods, except where the effect of including such securities would be antidilutive. Because the Company has reported net losses since inception, these potential common shares have been anti-dilutive and basic and diluted loss per share have been the same.

Basic and diluted net loss per share attributable to common stockholders was calculated as follows (in thousands, except share and per share data):

	Three Months Ended March 31,
	2021			2020
Numerator:
Net loss	$	(7,802	)	$	(4,232	)
Accretion of redeemable convertible preferred stock		—			(85	)
Net loss attributable to common stockholders	$	(7,802	)	$	(4,317	)
Denominator:
Weighted-average common shares—basic and diluted		12,945,546			230,860
Net loss per share attributable to common stockholders—basic and diluted	$	(0.60	)	$	(18.70	)

	Three Months Ended March 31,
	2021		2020
Series A-1 redeemable convertible preferred stock		—		986,466
Series A-2 redeemable convertible preferred stock		—		773,712
Series A-3 redeemable convertible preferred stock		—		872,031
Series A-4 redeemable convertible preferred stock		—		579,993
Series B redeemable convertible preferred stock		—		2,852,177
Series C redeemable convertible preferred stock		—		2,270,869
Warrants to purchase common stock		—		681,256
Stock options		1,762,605		901,678
Total		1,762,605		9,918,182

Recently Adopted Accounting Pronouncements

From time to time, new accounting pronouncements are issued by the FASB or other standard setting bodies and adopted by the Company as of the specified effective date.

In December 2019, the FASB issued ASU No. 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes (“ASU No. 2019-12”), which makes a number of changes meant to add or clarify guidance on accounting for income taxes. The Company adopted ASU 2019-12 on January 1, 2021. The adoption of ASU 2019-12 did not have a material impact on the Company’s consolidated financial position, results of operations or cash flows.

Summary of Significant Accounting Policies - Summary of Potentially Dilutive Securities Excluded from Calculation of Diluted Net Loss per Share (Details) - shares	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive securities excluded from calculation of diluted net loss per share	1,762,605	9,918,182
Series A-1 Redeemable Convertible Preferred Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive securities excluded from calculation of diluted net loss per share		986,466
Series A-2 Redeemable Convertible Preferred Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive securities excluded from calculation of diluted net loss per share		773,712
Series A-3 Redeemable Convertible Preferred Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive securities excluded from calculation of diluted net loss per share		872,031
Series A-4 Redeemable Convertible Preferred Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive securities excluded from calculation of diluted net loss per share		579,993
Series B Redeemable Convertible Preferred Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive securities excluded from calculation of diluted net loss per share		2,852,177
Series C Redeemable Convertible Preferred Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive securities excluded from calculation of diluted net loss per share		2,270,869
Warrants to Purchase Common Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive securities excluded from calculation of diluted net loss per share		681,256
Stock Options
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive securities excluded from calculation of diluted net loss per share	1,762,605	901,678

Accrued Expenses and Other Current Liabilities (Tables)

3 Months Ended

Mar. 31, 2021

Payables And Accruals [Abstract]

Schedule of Accrued Expenses and Other Current Liabilities

Accrued expenses and other current liabilities consist of the following (in thousands):

	March 31,		December 31,
	2021		2020
Payroll and employee related expenses	$	1,213	$	1,892
Third-party research and development expenses		195		381
Professional and consulting fees		523		555
Other		63		149
Total accrued expenses and other current liabilities	$	1,994	$	2,977

Summary of Significant Accounting Policies - Summary of Basic and Diluted Net Loss per Share Attributable to Common Stockholders (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Numerator:
Net loss	$ (7,802)	$ (4,232)
Accretion of redeemable convertible preferred stock		(85)
Net loss attributable to common stockholders	$ (7,802)	$ (4,317)
Denominator:
Weighted-average common shares outstanding—basic and diluted	12,945,546	230,860
Net loss per share attributable to common stockholders—basic and diluted	$ (0.60)	$ (18.70)

- Definition

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

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- Definition

Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities; of income (loss) available to common shareholders.

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+ Details

Condensed Consolidated Statements of Redeemable Convertible Preferred Stock and Stockholders' Equity (Deficit) (unaudited) - USD ($) $ in Thousands	Total	Redeemable Convertible Preferred Stock	Series C Redeemable Convertible Preferred Stock	Common Stock	Additional Paid-in Capital	Accumulated Deficit
Balance at Dec. 31, 2019	$ (123,338)	$ 130,666			$ 4,419	$ (127,757)
Balance, Shares at Dec. 31, 2019		209,119,674		230,860
Issuance of Series C redeemable convertible preferred stock, net of issuance costs			$ 29,446
Issuance of Series C redeemable convertible preferred stock, net of issuance costs, Shares			78,306,611
Accretion of convertible preferred stock to redemption value	(85)				(85)
Temporary equity, Accretion of convertible preferred stock to redemption value		$ 85
Issuance of common stock warrants in conjunction with sale of Series C redeemable convertible preferred stock	740				740
Stock-based compensation	134				134
Net loss	(4,232)					(4,232)
Balance at Mar. 31, 2020	(126,781)	$ 160,197			5,208	(131,989)
Balance, Shares at Mar. 31, 2020		287,426,285		230,860
Balance at Dec. 31, 2020	74,492			$ 13	224,363	(149,884)
Balance, Shares at Dec. 31, 2020				12,932,377
Exercise of common stock options	$ 262				262
Exercise of common stock options, Shares	30,391			30,391
Stock-based compensation	$ 599				599
Net loss	(7,802)					(7,802)
Balance at Mar. 31, 2021	$ 67,551			$ 13	$ 225,224	$ (157,686)
Balance, Shares at Mar. 31, 2021				12,962,768

Organization and Basis of Presentation

3 Months Ended

Mar. 31, 2021

Organization Consolidation And Presentation Of Financial Statements [Abstract]

Organization and Basis of Presentation

1. Organization and Basis of Presentation

Lyra Therapeutics, Inc. (the “Company”) is a clinical-stage therapeutics company focused on the development and commercialization of novel integrated drug and delivery solutions for the localized treatment of patients with ear, nose and throat (“ENT”) diseases. The Company’s proprietary technology platform, XTreo, is designed to precisely and consistently deliver medicines directly to the affected tissue for sustained periods with a single administration. The Company’s initial product candidates, LYR-210 and LYR-220, are bioresorbable polymeric matrices designed to be administered in a brief, non-invasive, in-office procedure and intended to deliver up to six months of continuous drug therapy to the sinonasal passages for the treatment of chronic rhinosinusitis (“CRS”). The Company was incorporated as a Delaware corporation on November 21, 2005 and is located in Watertown, Massachusetts.

The Company is subject to risks common to companies in the therapeutics and pharmaceutical industry, including but not limited to, risks of failure of preclinical studies and clinical trials, the need to obtain marketing approval for any drug product candidate that it may identify and develop, the need to successfully commercialize and gain market acceptance of its product candidates, dependence on key personnel, protection of proprietary technology, compliance with government regulations, development by competitors of technological innovations, reliance on third party manufacturers, ability to transition from pilot-scale manufacturing to large-scale production of products and the need to obtain adequate additional financing to fund the development of its product candidates.

Prior to our initial public offering (“IPO”), the Company has funded its operations with proceeds from sales of redeemable convertible preferred stock and funding from government contracts. The Company has incurred recurring net losses since inception and had net losses of approximately $7.8 million and $4.2 million for the three months ended March 31, 2021 and 2020, respectively. In addition, the Company has an accumulated deficit of approximately $157.7 million at March 31, 2021. The Company expects to continue to generate operating losses for the foreseeable future. At March 31, 2021, the Company had approximately $66.1 million of cash and cash equivalents.

On May 5, 2020, the Company completed its IPO, in which the Company issued and sold 4,025,000 shares of its common stock, including 525,000 shares pursuant to the full exercise of the underwriters’ option to purchase additional shares, at a public offering price of $16.00 per share, for aggregate gross proceeds of $64.4 million. The Company received approximately $57.3 million in net proceeds after deducting underwriting discounts and offering expenses paid by the Company.

The Company believes that its cash and cash equivalents as of March 31, 2021 will be sufficient to fund the Company’s operating plan for a period of at least one year from the issuance date of the condensed consolidated financial statements. The Company will need additional financing to support its continuing operations and pursue its growth strategy. Until such time as the Company can generate significant revenue from product sales, if ever, it expects to finance its operations through a combination of equity or debt financings, collaboration agreements, strategic alliances and licensing arrangements. The Company may be unable to raise additional funds or enter into such other agreements when needed on favorable terms or at all. The inability to obtain funding as and when needed would have a negative impact on the Company’s financial condition and ability to pursue its business strategies. If the Company is unable to obtain funding when needed, the Company could be forced to delay, reduce or eliminate some or all of its research and development programs, product portfolio expansion or commercialization efforts, which could adversely affect its business prospects, or the Company may be unable to continue operations. The Company will need to generate significant revenue to achieve profitability, and it may never do so.

Upon the completion of the IPO of its common stock in May 2020, all outstanding redeemable convertible preferred stock of the Company converted into shares of common stock and all outstanding warrants to purchase common stock were automatically cashless exercised.

COVID-19 Pandemic and CARES Act

Basis of Presentation

Preferred and Common Stock

3 Months Ended

Mar. 31, 2021

Equity [Abstract]

Preferred and Common Stock

6. Preferred and Common Stock

On May 5, 2020, the Company filed a restated certificate of incorporation which authorizes its Board of Directors to issue up to 200,000,000 shares of common stock, par value $0.001 per share and 10,000,000 shares of undesignated preferred stock, par value $0.001 per share.

The holders of common stock are entitled to one vote for each share held. Common stockholders are not entitled to receive dividends, unless declared by the Board of Directors.

The Company’s Board of Directors approved a one-for-34.483 reverse stock split of its issued and outstanding common stock and stock options and a proportional adjustment to the existing conversion ratios for the Company’s redeemable convertible preferred stock pursuant to an amendment to the Company’s amended and restated certificate of incorporation effective as of April 27, 2020. Accordingly, all common stock shares, per share amounts, and additional paid in capital amounts for all periods presented in the accompanying condensed consolidated financial statements and notes thereto have been retroactively adjusted, where applicable, to reflect the reverse stock split.

In May 2020, the Company completed its IPO in which the Company issued and sold 4,025,000 shares of its common stock, including 525,000 shares pursuant to the full exercise of the underwriters’ option to purchase additional shares, at a public offering price of $16.00 per share, for aggregate gross proceeds of $64.4 million. The Company received approximately $57.3 million in net proceeds after deducting underwriting discounts and offering expenses paid by the Company. In connection with this financing, all outstanding shares of redeemable convertible preferred stock converted into 8,335,248 shares of the Company’s common stock, all outstanding Warrants were automatically cashless exercised resulting in the issuance of 313,794 shares of the Company’s stock and the issuance to one of our directors, in lieu of compensation payable by the Company under a consulting agreement, of 19,661 fully vested shares of the Company’s common stock.

The Company has reserved for future issuances the following shares of common stock as of March 31, 2021:

	As of March 31, 2021
Stock options		3,375,557
Employee stock purchase plan		214,661
Total		3,590,218

Warrants

In conjunction with the issuance of the Series C Preferred Stock, the Company issued Warrants to purchase 681,256 shares of common stock at an exercise price of $8.63 per share.

The Company classified the Warrants as equity in the condensed consolidated balance sheets in accordance with the guidance in ASC 815, Derivatives and Hedging. The Company allocated the net proceeds from the issuance of the Series C Preferred Stock based on the relative fair values of the Series C Preferred Stock and Warrants, which resulted in approximately $0.7 million of the net proceeds being allocated to the Warrants.

Upon the completion of the IPO of its common stock in May 2020, all outstanding Warrants were automatically cashless exercised resulting in the issuance of 313,794 shares of the Company’s common stock.

Summary of Significant Accounting Policies

3 Months Ended

Mar. 31, 2021

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

2. Summary of Significant Accounting Policies

The Company’s significant accounting policies are disclosed in the audited consolidated financial statements for the year ended December 31, 2020, included in the Company’s Annual Report on Form 10-K filed with the SEC on March 9, 2021. Since the date of those financial statements, there have been no changes to its significant accounting policies except as noted below.

Use of Estimates

Restricted Cash

Concentrations of Credit Risk and Off-Balance Sheet Risk

The Company has no significant off-balance sheet risk such as foreign exchange contracts, option contracts, or other foreign exchange hedging arrangements.

Net Loss per Share

Basic and diluted net loss per share attributable to common stockholders was calculated as follows (in thousands, except share and per share data):

	Three Months Ended March 31,
	2021			2020
Numerator:
Net loss	$	(7,802	)	$	(4,232	)
Accretion of redeemable convertible preferred stock		—			(85	)
Net loss attributable to common stockholders	$	(7,802	)	$	(4,317	)
Denominator:
Weighted-average common shares—basic and diluted		12,945,546			230,860
Net loss per share attributable to common stockholders—basic and diluted	$	(0.60	)	$	(18.70	)

	Three Months Ended March 31,
	2021		2020
Series A-1 redeemable convertible preferred stock		—		986,466
Series A-2 redeemable convertible preferred stock		—		773,712
Series A-3 redeemable convertible preferred stock		—		872,031
Series A-4 redeemable convertible preferred stock		—		579,993
Series B redeemable convertible preferred stock		—		2,852,177
Series C redeemable convertible preferred stock		—		2,270,869
Warrants to purchase common stock		—		681,256
Stock options		1,762,605		901,678
Total		1,762,605		9,918,182

Recently Adopted Accounting Pronouncements

From time to time, new accounting pronouncements are issued by the FASB or other standard setting bodies and adopted by the Company as of the specified effective date.

Leases

3 Months Ended

Mar. 31, 2021

Leases [Abstract]

Leases

9. Leases

In August 2007, the Company entered into an operating lease, as amended, for approximately 22,343 square feet of office and laboratory space in Watertown, Massachusetts. In November 2017, the Company amended its lease (“2017 Amendment”) and extended the lease term through April 2023. Initial base rent under the 2017 Amendment was approximately $1.0 million per year. The 2017 Amendment includes annual rent escalations over the term of the operating lease. The Company maintains a letter of credit of approximately $0.3 million securing its obligations under the operating lease which is secured by approximately $0.3 million of certificate of deposits, which are included as restricted cash in the consolidated balance sheets. Rent expense is recognized on a straight-line basis over the terms of occupancy.

In addition to the lease discussed above, the Company is party to an April 2020 lease for office equipment that expires in June 2024. The equipment lease is accounted for as an operating lease.

The components of lease cost recorded in the Company’s condensed consolidated financial statements were as follows (in thousands):

	Three Months Ended March 31,
	2021		2020
Lease Cost:
Operating lease cost	$	264	$	263
Variable lease cost		119		193
Total lease cost	$	383	$	456

Variable lease payments include the Company’s allocated share of costs incurred and expenditures made by the landlord in the operation and management of the building.

The weighted-average remaining lease term and discount rate related to the Company’s operating leases were as follows:

	As of March 31, 2021
Weighted-average remaining lease term (in years)		2.1
Weighted-average discount rate		5.5	%

Maturity of the Company’s operating lease liabilities in accordance with ASC 842 as of March 31, 2021 were as follows (in thousands):

Year ending December 31,
Remainder of 2021	$	827
2022		1,127
2023		382
2024		2
Total maturities		2,338
Less: Amount representing interest		(135	)
Present value of operating lease liability		2,203
Less: Current portion of operating lease liability		(1,007	)
Total operating lease liability, net of current portion	$	1,196

Fair Value Measurements

3 Months Ended

Mar. 31, 2021

Fair Value Disclosures [Abstract]

Fair Value Measurements

3. Fair Value Measurements

The Company did not have financial assets and liabilities measured at fair value at March 31, 2021 and December 31, 2020.

There have been no changes to the valuation methods used during the three months ended March 31, 2021 and 2020. There were no transfers within the fair value hierarchy during the three months ended March 31, 2021 and 2020.

The carrying values of the Company’s accounts payable and accrued expenses approximate their fair values due to the short-term nature of these liabilities.

In connection with the Company’s sale of Series C redeemable convertible preferred stock (“Series C Preferred Stock”) in January 2020, the Company issued to investors warrants for the purchase of common stock (“Warrants”). The proceeds from the issuance of the Series C Preferred Stock were allocated between the Series C Preferred Stock and Warrants based on their relative fair values at the time of issuance.

- Definition

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

+ References + Details

Leases - Summary of Maturity of Operating Lease Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Leases [Abstract]
Remainder of 2021	$ 827
2022	1,127
2023	382
2024	2
Total maturities	2,338
Less: Amount representing interest	(135)
Present value of operating lease liability	2,203
Present value of operating lease liability	2,203
Less: Current portion of operating lease liability	(1,007)	$ (985)
Operating lease liabilities, net of current portion	$ 1,196	$ 1,454

Condensed Consolidated Statements of Cash Flows (unaudited) - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Cash flows from operating activities:
Net loss	$ (7,802,000)	$ (4,232,000)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation	599,000	134,000
Depreciation expense	70,000	8,000
Changes in assets and liabilities:
Prepaid expenses and other current assets	78,000	18,000
Operating lease right-of-use assets	232,000	219,000
Accounts payable	452,000	432,000
Accrued expenses and other current liabilities	(983,000)	(381,000)
Operating lease liabilities	(236,000)	(215,000)
Net cash used in operating activities	(7,590,000)	(4,017,000)
Cash flows from investing activities:
Purchases of property and equipment	(1,160,000)	(8,000)
Net cash used in investing activities	(1,160,000)	(8,000)
Cash flows from financing activities:
Payment of deferred offering costs		(773,000)
Proceeds from exercise of stock options	262,000
Net cash provided by financing activities	262,000	29,464,000
Net (decrease) increase in cash and cash equivalents	(8,488,000)	25,439,000
Cash and cash equivalents and restricted cash, beginning of period	74,922,000	10,137,000
Cash and cash equivalents and restricted cash, end of period	$ 66,434,000	35,576,000
Supplemental disclosure of non-cash financing and investing activities:
Property and equipment purchases included in accounts payable		49,000
Accretion of redeemable convertible preferred stock to redemption value		85,000
Deferred offering costs included in accounts payable and accrued expense		702,000
Series C Preferred Stock
Cash flows from financing activities:
Proceeds from the sale of Series C redeemable convertible preferred stock		30,392,000
Payment of offering costs related to sale of Series C redeemable convertible preferred stock		(155,000)
Supplemental disclosure of non-cash financing and investing activities:
Allocation of Series C redeemable convertible preferred stock to common stock warrant		740,000
Series C redeemable convertible preferred stock stock issuance costs included in accounts payable and accrued expense		$ 51,000

Property and Equipment - Schedule of Property and Equipment (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 6,116	$ 5,043
Accumulated depreciation	(2,948)	(2,878)
Property and equipment, net	3,168	2,165
Laboratory Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	3,539	3,277
Computer Software and Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	668	650
Office Furniture and Fixtures
Property Plant And Equipment [Line Items]
Property and equipment, gross	301	301
Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and equipment, gross	317	317
Construction in Progress
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 1,291	$ 498

Summary of Significant Accounting Policies - Additional Information (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Accounting Policies [Abstract]
Restricted cash	$ 0.3	$ 0.3

Property and Equipment (Tables)

3 Months Ended

Mar. 31, 2021

Property Plant And Equipment [Abstract]

Schedule of Property and Equipment

Property and equipment consist of the following at March 31, 2021 and December 31, 2020 (in thousands):

	March 31,			December 31,
	2021			2020
Property and equipment:
Laboratory equipment	$	3,539		$	3,277
Computer software and equipment		668			650
Office furniture and fixtures		301			301
Leasehold improvements		317			317
Construction in progress		1,291			498
	$	6,116		$	5,043
Accumulated depreciation		(2,948	)		(2,878	)
Property and equipment, net	$	3,168		$	2,165

Preferred and Common Stock - Schedule of Common Stock Reserved for Future Issuances (Details)	Mar. 31, 2021 shares
Class Of Stock [Line Items]
Shares of common stock reserved for future issuances	3,590,218
Stock Options
Class Of Stock [Line Items]
Shares of common stock reserved for future issuances	3,375,557
Employee stock purchase plan
Class Of Stock [Line Items]
Shares of common stock reserved for future issuances	214,661

Stock-Based Compensation Expense - Summary of Stock Option Activity Under Plans (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Dec. 31, 2020
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Shares, Outstanding December 31, 2020	1,428,886
Shares, Granted	365,700
Shares, Exercised	(30,391)
Shares, Cancelled	(1,590)
Shares, Outstanding at March 31, 2021	1,762,605	1,428,886
Shares, Exercisable at March 2021	665,936
Shares, Vested and expected to vest at March 31, 2021	1,762,605
Weighted Average Exercise Price, Outstanding December 31, 2020	$ 10.41
Weighted Average Exercise Price, Granted	10.75
Weighted Average Exercise Price, Exercised	8.63
Weighted Average Exercise Price, Cancelled	11.70
Weighted Average Exercise Price, Outstanding at March 31,2021	10.51	$ 10.41
Weighted Average Exercise Price, Exercisable at March 31, 2021	9.39
Weighted Average Exercise Price, Vested and expected to vest at March 31, 2021	$ 10.51
Outstanding, Weighted Average Remaining Contractual Life (in years)	8 years 1 month 6 days	7 years 8 months 12 days
Exercisable, Weighted Average Remaining Contractual Life (in years)	6 years 3 months 19 days
Vested and expected to vest, Weighted Average Remaining Contractual Life (in years)	8 years 1 month 6 days
Aggregate Intrinsic Value, Outstanding December 31, 2020	$ 5,540	$ 5,165
Aggregate Intrinsic Value, Exercisable at March 31, 2021	3,349
Aggregate Intrinsic Value, Vested and expected to vest at March 31, 2021	$ 5,540