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Term Loan - Schedule of Future Principal Payments (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Debt Disclosure [Abstract]
2024 (remaining 9 months)	$ 1,384
2025	1,714
2026	136
Total	3,234
Less: interest	(260)
Term Loan, gross	2,974
Less: unamortized debt issuance costs	(31)
Less: Term Loan, current portion	(1,622)	$ (1,622)
Term loan, net of current portion	$ 1,321	$ 1,717

Leases - Additional Information (Details) - South San Francisco, California - ft²	1 Months Ended	3 Months Ended
	Dec. 31, 2022	Mar. 31, 2024
Lessee, Lease, Description [Line Items]
Area of office space	6,500
Operating lease commencement date	2022-12
Operating lease termination date	2028-02
Operating Leases, option to renew lease term description		The Company has an option to extend the lease term of the South San Francisco Lease for an additional three years which has not been included in the lease term as it is not reasonably certain that the Company will exercise this option.
Operating leases, renew lease term	3 years

Organization and Principal Activities	3 Months Ended
Mar. 31, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Principal Activities	1. Organization and Principal Activities Description of Business Spruce Biosciences, Inc. (the “Company”) is a late-stage biopharmaceutical company focused on developing and commercializing novel therapies for rare endocrine disorders with significant unmet medical need. The Company is initially developing its wholly-owned product candidate, tildacerfont, as the potential first non-steroidal therapy for patients suffering from classic congenital adrenal hyperplasia (“CAH”). The Company is located in South San Francisco, California and was incorporated in the state of Delaware in April 2016. Private Placement of Common Stock and Warrants In February 2023, the Company entered into a Securities Purchase Agreement (the “Purchase Agreement”) with certain institutional investors (the “Purchasers”), pursuant to which the Company agreed to sell and issue (i) 16,116,000 shares of the Company’s common stock (“Common Stock”), (ii) pre-funded warrants to purchase 800,000 shares of Common Stock (the “Pre-Funded Warrants”) to a Purchaser and (iii) 12,687,000 warrants to purchase Common Stock (the “Standard Warrants” and together with the Pre-Funded Warrants, the “Warrants”) in a private placement transaction (the “Private Placement”). The total gross proceeds to the Company were approximately $53.6 million, which does not include any proceeds that may be received upon exercise of the Standard Warrants. Open Market Sales Agreement In February 2022, the U.S. Securities and Exchange Commission (“SEC”) declared effective a registration statement on Form S-3 (the “Shelf Registration”), covering the sale of up to $200.0 million of the Company's securities. Also, in February 2022, the Company entered into an Open Market Sales AgreementSM (the “Sales Agreement”) with Jefferies LLC (“Jefferies”) pursuant to which the Company may elect to issue and sell, from time to time, shares of Common Stock having an aggregate offering price of up to $21.0 million under the Shelf Registration through Jefferies acting as the sales agent and/or principal. As of March 31, 2024, the Company has not issued any shares of Common Stock under the Sales Agreement. Liquidity and Capital Resources The Company believes that based on its current operating plan, its cash and cash equivalents of $81.2 million as of March 31, 2024 will be sufficient to fund its planned operations and debt obligations for at least 12 months following the issuance date of these financial statements. The Company has incurred significant losses and negative cash flows from operations. During the three months ended March 31, 2024, the Company incurred a net loss of $11.6 million and used $15.0 million of cash in operations. As of March 31, 2024, the Company had an accumulated deficit of $208.9 million and does not expect positive cash flows from operations in the foreseeable future. The Company has funded its operations primarily through the issuance and sale of equity securities, debt and collaboration revenue. The Company anticipates that it will need to raise substantial additional financing in the future to fund its operations. In order to meet these additional cash requirements, the Company may seek to out-license rights to develop and commercialize tildacerfont or sell additional equity or issue debt, convertible debt or other securities that may result in dilution to its stockholders. If the Company raises additional funds through the issuance of debt or convertible debt securities, these securities could have rights senior to those of its shares of Common Stock and could contain covenants that restrict its operations. There can be no assurance that the Company will be able to obtain additional equity or debt financing on terms acceptable to it, if at all. Additional debt financing, if available, would result in increased fixed payment obligations and may involve agreements that include covenants limiting or restricting the Company’s ability to take specific actions such as incurring debt, making capital expenditures or declaring dividends. The Company’s failure to obtain sufficient funds on acceptable terms when needed could have a material adverse effect on its business, results of operations, and financial condition.

Organization and Principal Activities

3 Months Ended

Mar. 31, 2024

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Organization and Principal Activities

1. Organization and Principal Activities

Description of Business

Spruce Biosciences, Inc. (the “Company”) is a late-stage biopharmaceutical company focused on developing and commercializing novel therapies for rare endocrine disorders with significant unmet medical need. The Company is initially developing its wholly-owned product candidate, tildacerfont, as the potential first non-steroidal therapy for patients suffering from classic congenital adrenal hyperplasia (“CAH”). The Company is located in South San Francisco, California and was incorporated in the state of Delaware in April 2016.

Private Placement of Common Stock and Warrants

In February 2023, the Company entered into a Securities Purchase Agreement (the “Purchase Agreement”) with certain institutional investors (the “Purchasers”), pursuant to which the Company agreed to sell and issue (i) 16,116,000 shares of the Company’s common stock (“Common Stock”), (ii) pre-funded warrants to purchase 800,000 shares of Common Stock (the “Pre-Funded Warrants”) to a Purchaser and (iii) 12,687,000 warrants to purchase Common Stock (the “Standard Warrants” and together with the Pre-Funded Warrants, the “Warrants”) in a private placement transaction (the “Private Placement”). The total gross proceeds to the Company were approximately $53.6 million, which does not include any proceeds that may be received upon exercise of the Standard Warrants.

Open Market Sales Agreement

In February 2022, the U.S. Securities and Exchange Commission (“SEC”) declared effective a registration statement on Form S-3 (the “Shelf Registration”), covering the sale of up to $200.0 million of the Company's securities. Also, in February 2022, the Company entered into an Open Market Sales AgreementSM (the “Sales Agreement”) with Jefferies LLC (“Jefferies”) pursuant to which the Company may elect to issue and sell, from time to time, shares of Common Stock having an aggregate offering price of up to $21.0 million under the Shelf Registration through Jefferies acting as the sales agent and/or principal. As of March 31, 2024, the Company has not issued any shares of Common Stock under the Sales Agreement.

Liquidity and Capital Resources

The Company believes that based on its current operating plan, its cash and cash equivalents of $81.2 million as of March 31, 2024 will be sufficient to fund its planned operations and debt obligations for at least 12 months following the issuance date of these financial statements.

The Company has incurred significant losses and negative cash flows from operations. During the three months ended March 31, 2024, the Company incurred a net loss of $11.6 million and used $15.0 million of cash in operations. As of March 31, 2024, the Company had an accumulated deficit of $208.9 million and does not expect positive cash flows from operations in the foreseeable future. The Company has funded its operations primarily through the issuance and sale of equity securities, debt and collaboration revenue.

The Company anticipates that it will need to raise substantial additional financing in the future to fund its operations. In order to meet these additional cash requirements, the Company may seek to out-license rights to develop and commercialize tildacerfont or sell additional equity or issue debt, convertible debt or other securities that may result in dilution to its stockholders. If the Company raises additional funds through the issuance of debt or convertible debt securities, these securities could have rights senior to those of its shares of Common Stock and could contain covenants that restrict its operations. There can be no assurance that the Company will be able to obtain additional equity or debt financing on terms acceptable to it, if at all. Additional debt financing, if available, would result in increased fixed payment obligations and may involve agreements that include covenants limiting or restricting the Company’s ability to take specific actions such as incurring debt, making capital expenditures or declaring dividends. The Company’s failure to obtain sufficient funds on acceptable terms when needed could have a material adverse effect on its business, results of operations, and financial condition.

Summary of Significant Accounting Policies	3 Months Ended
Summary of Significant Accounting Policies	Mar. 31, 2024
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies Basis of Presentation The financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) and applicable rules and regulations of the SEC for interim reporting. As permitted under those rules and regulations, certain notes or other financial information normally included in financial statements prepared in accordance with U.S. GAAP have been condensed or omitted. The condensed balance sheet as of March 31, 2024, the condensed statements of operations and comprehensive loss for the three months ended March 31, 2024 and 2023, the condensed statement of stockholders’ equity for the three months ended March 31, 2024 and 2023, and the condensed statements of cash flows for the three months ended March 31, 2024 and 2023 are unaudited. The interim condensed financial statements have been prepared on the same basis as the annual financial statements and, in the opinion of management, reflect all adjustments, which include only normal, recurring adjustments that are necessary to present fairly the Company’s results for the interim periods presented. The condensed balance sheet as of December 31, 2023 is derived from the Company’s audited financial statements. The results of operations for the three months ended March 31, 2024 are not necessarily indicative of the results to be expected for the year ending December 31, 2024, or for any other future annual or interim period. These interim condensed financial statements should be read in conjunction with the Company’s Annual Report on Form 10-K for the year ended December 31, 2023 filed with the SEC on March 18, 2024 (“Annual Report”). Use of Estimates 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, liabilities and expenses as well as related disclosure of contingent assets and liabilities. Significant estimates and assumptions reflected in these financial statements include, but are not limited to, accrued research and development expenses, revenue recognition, stock-based compensation, and uncertain tax positions. The Company bases its estimates on its historical experience and on assumptions that it believes are reasonable; however, actual results could significantly differ from those estimates. Risks and Uncertainties Any product candidates developed by the Company will require approvals from the U.S. Food and Drug Administration or foreign regulatory agencies prior to commercial sales. There can be no assurance that the Company’s current and future product candidates will meet desired efficacy and safety requirements to obtain the necessary approvals. If approval is denied or delayed, it may have a material adverse impact on the Company’s business and its financial statements. The Company is subject to a number of risks similar to other late-stage biopharmaceutical companies including, but not limited to, dependency on the clinical success of the Company’s product candidate, tildacerfont, ability to obtain regulatory approval of tildacerfont, the need for substantial additional financing to achieve its goals, uncertainty of broad adoption of its approved products, if any, by physicians and consumers, significant competition, untested manufacturing capabilities, and dependence on key individuals and sole source suppliers. Global economic and business activities continue to face widespread macroeconomic and geopolitical uncertainties, including recent and potential future disruptions in access to bank deposits or lending commitments due to bank failures, labor shortages, inflation and monetary supply shifts, recession risks and potential disruptions from the ongoing wars in Ukraine and Israel and related sanctions. The Company continues to actively monitor the impact of these macroeconomic and geopolitical factors on its financial condition, liquidity, operations, and workforce. The extent of the impact of these factors on the Company’s operational and financial performance, including its ability to execute its business strategies and initiatives in the expected time frame, will depend on future developments, which are uncertain and cannot be predicted; however, any continued or renewed disruption resulting from these factors could negatively impact the Company’s business. Concentration of Credit Risk Financial instruments, which potentially subject the Company to significant concentration of credit risk, consist primarily of cash and cash equivalents. The Company maintains deposits in federally insured financial institutions in excess of federally insured limits. The Company is exposed to credit risk in the event of default by the financial institutions holding its cash and cash equivalents to the extent recorded in the condensed balance sheets. Significant Accounting Policies There have been no significant changes to the significant accounting policies during the three months ended March 31, 2024, as compared to the significant accounting policies described in the Annual Report. Emerging Growth Company Status The Company is an emerging growth company as defined in the Jumpstart Our Business Startups Act of 2012 (“JOBS Act”) and may take advantage of reduced reporting requirements that are otherwise applicable to public companies. Section 107 of the JOBS Act exempts emerging growth companies from being required to comply with new or revised financial accounting standards until private companies are required to comply with those standards. The Company has elected to use the extended transition period for complying with new or revised accounting standards. Recent Accounting Pronouncements - Not Yet Adopted In December 2023, the FASB issued Accounting Standards Update 2023-09, Income Taxes - Improvements to Income Tax Disclosures (“ASU 2023-09”) requiring enhancements and further transparency to certain income tax disclosures, most notably the tax rate reconciliation and income taxes paid. ASU 2023-09 is effective for fiscal years beginning after December 15, 2024 on a prospective basis and retrospective application is permitted. The Company is currently evaluating the impact of the adoption of this standard on the Company’s financial statements and related disclosures. In November 2023, the FASB issued ASU 2023-07, Improvements to Reportable Segment Disclosures (“ASU 2023-07”) which is intended to improve reportable segment disclosure requirements, primarily through additional disclosures about significant segment expenses, including for single reportable segment entities. The standard is effective for fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024, with early adoption permitted. The amendments should be applied retrospectively to all prior periods presented in the financial statements. The Company is currently evaluating the disclosure requirements related to the new standard.

Fair Value Measurements - Summary of Financial Assets Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Cash and Cash Equivalents
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents and available for sale securities, amortized cost	$ 79,985	$ 95,875
Available for sale, fair value	79,985	95,875
Level 1 \| Money Market Funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents and available for sale securities, amortized cost	79,985	95,875
Available for sale, fair value	$ 79,985	$ 95,875

Term Loan

3 Months Ended

Mar. 31, 2024

Debt Disclosure [Abstract]

Term Loan

6. Term Loan

In September 2019, the Company entered into a Loan and Security Agreement, as subsequently amended (the “Loan Agreement”) with Silicon Valley Bank (“SVB”) providing for a term loan (the “Term Loan”) for an aggregate principal amount of $4.5 million.

In September 2019 and in connection with the Loan Agreement, the Company issued a warrant to purchase up to an aggregate of 49,609 shares of Common Stock at $1.44 per share. The Company determined the initial fair value of the warrant to be $0.1 million using the Black-Scholes option-pricing model. The fair value of the warrant was recorded to equity and as a debt discount, which was being amortized to interest expense using the effective interest method over the term of the Term Loan. In November 2020, the warrant was net-exercised for 46,358 shares of Common Stock.

In March 2021, the Company entered into a First Amendment to Loan and Security Agreement (the “First Amendment”), which increased the aggregate principal amount of the Term Loan to $30.0 million, of which $20.0 million was immediately available under the first tranche (“First Tranche”) and $10.0 million was available under the second tranche through December 31, 2022 (“Second Tranche”), subject to the completion of certain clinical or financial milestones. Pursuant to the First Amendment, the Term Loan will mature on January 1, 2026 (the “Maturity Date”).

In May 2022, the Company entered into a Second Amendment to Loan and Security Agreement (the “Second Amendment”), which amended the milestones for the Second Tranche, added a liquidity covenant for the Second Tranche and amended the interest and prepayment terms.

As of March 31, 2024, the carrying value of the Term Loan was $2.9 million, consisting of the outstanding principal under the First Tranche of $3.0 million, less unamortized debt discount and issuance costs of $31 thousand, which are being amortized using the effective interest method over the life of the Term Loan. Commitments available under the Second Tranche of $10.0 million expired on December 31, 2022.

The Loan Agreement provided for monthly cash interest-only payments following the funding date of each respective tranche and continuing thereafter through December 31, 2022. The Term Loan is subject to a floating per annum interest rate equal to the greater of (a) 0.50% above the Prime Rate (as defined in the Loan Agreement) or (b) 3.75%. Following the interest-only period, the outstanding Term Loan balance is payable in (i) 37 consecutive monthly payments after the end of the interest-only period and continuing on the same day of each month thereafter, in amounts that would fully amortize such Term Loan balance, as of the first business day of the first month following the amended interest-only period, over the repayment period, plus (ii) monthly payments of

accrued but unpaid interest. As of March 31, 2024 and December 31, 2023, the stated interest rate of the Term Loan was 9.0%, respectively.

The final payment is due on the Maturity Date and includes all outstanding principal plus accrued unpaid interest and an end of term payment totaling $0.3 million, which is 6.0% of the original funded principal amount of the First Tranche (the “Supplemental Final Payment”). The Company may prepay amounts outstanding under the Term Loan at any time provided certain notification conditions are met, in which case, all outstanding principal plus accrued and unpaid interest, the Supplemental Final Payment, a prepayment fee of 1% or 2% of the principal amount of the First Tranche, and any bank expenses become due and payable.

The Company is subject to customary affirmative and restrictive covenants under the Loan Agreement. The Company’s obligations under the Loan Agreement are secured by a first priority security interest in substantially all of its current and future assets, other than intellectual property. The Company also agreed not to encumber its intellectual property assets, except as permitted by the Loan Agreement.

The Loan Agreement also contains customary indemnification obligations and customary events of default, including, among other things, the Company’s failure to fulfill certain obligations under the Loan Agreement and the occurrence of a material adverse change in its business, operations, or condition (financial or otherwise), a material impairment of the prospect of repayment of any portion of the loan, or a material impairment in the perfection or priority of lender’s lien in the collateral or in the value of such collateral. In the event of default by the Company under the Loan Agreement, the lender would be entitled to exercise their remedies thereunder, including the right to accelerate the debt, upon which the Company may be required to repay all amounts then outstanding under the Loan Agreement. As of March 31, 2024, the Company was in compliance with all covenants under the Loan Agreement and there has been no material adverse change.

As of March 31, 2024, future payments of principal and interest are as follows (in thousands):


Year ending December 31,
2024 (remaining 9 months)	$	1,384
2025		1,714
2026		136
Total	$	3,234
Less: interest		(260	)
Term loan, gross	$	2,974
Less: unamortized debt issuance costs		(31	)
Less: term loan, current portion		(1,622	)
Term loan, net of current portion	$	1,321

- Definition

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
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-Name Accounting Standards Codification
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-Paragraph 1B
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Collaboration and License Agreements - Additional Information (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		12 Months Ended
	Apr. 30, 2023	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2016	Dec. 31, 2023
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Potential Additional Cash Receipt		$ 65,000
Research and development		10,317	$ 11,712
Collaboration revenue		2,002	$ 1,964
Deferred revenue		2,908			$ 4,911
Kaken License Agreement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Upfront payments	$ 15,000	15,000
Eli Lilly And Company [Member] \| Lilly License Agreement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Potential Additional Payment		23,000
Research and development arrangement, costs incurred		$ 0
Research and development				$ 800

Collaboration and License Agreements

3 Months Ended

Mar. 31, 2024

Research and Development [Abstract]

Collaboration and License Agreements

7. Collaboration and License Agreements

Eli Lily and Company

In May 2016, the Company entered into a license agreement (the “Lilly License Agreement”), with Eli Lilly and Company (“Lilly”). Pursuant to the terms of the Lilly License Agreement, Lilly granted the Company an exclusive, worldwide, royalty bearing, sublicensable license under certain technology, patent rights, know-how and proprietary materials related to certain compounds, to research, develop, and commercialize such compounds for all pharmaceutical uses.

As partial consideration for the rights granted to the Company under the Lilly License Agreement, the Company made a one-time upfront payment to Lilly of $0.8 million during the year ended December 31, 2016, which was recorded as research and development expense as there was no alternative use due to the early stage of the technology. The Company is also required to pay Lilly up to an aggregate of $23.0 million upon the achievement, during the time the Lilly License Agreement remains in effect, of certain milestones relating to the clinical development and commercial sales of products licensed under the Lilly License Agreement. Such payments are for predetermined fixed amounts, are paid only upon the first occurrence of each event, and are due shortly after achieving the applicable milestone. In addition, the Company is required to pay Lilly tiered royalties on annual worldwide net sales with rates ranging from mid-single-digits to sub-teens. No additional amounts were paid by the Company to Lilly during any of the periods presented, nor were due as of such dates pursuant to the Lilly License Agreement.

The Lilly License Agreement will remain in effect, unless earlier terminated, until the expiration of the royalty payment obligations. Royalties are payable on a product-by-product and country-by-country basis from the first commercial sale of the product until the later of (i) the tenth anniversary of the date of first commercial sale in such country, (ii) the expiration in such country of the last-to-expire licensed patent having a valid claim covering the manufacture, use or sale of the licensed product as commercialized in such country, and (iii) the expiration of any data or regulatory exclusivity period for the licensed product in such country.

Kaken Pharmaceutical Co, Ltd.

On January 5, 2023, the Company entered into a collaboration and license agreement (the “Kaken License Agreement”) with Kaken Pharmaceutical Co, Ltd. (“Kaken”). Under the terms of the Kaken License Agreement, the Company granted to Kaken the exclusive right to develop, manufacture and commercialize the Company’s product candidate, tildacerfont, for the treatment of CAH in Japan. Pursuant to the Kaken License Agreement, Kaken will be responsible for securing and maintaining regulatory approvals necessary to commercialize tildacerfont in Japan. The Company will retain all rights to tildacerfont in all other geographies.

Pursuant to the Kaken License Agreement, Kaken made an upfront payment to the Company of $15.0 million in April 2023. In addition to the upfront payment, the Company is entitled to receive up to an aggregate of approximately $65.0 million (at exchange rates in effect on the date of the Kaken License Agreement) upon the achievement of specified milestones related to the development, regulatory approval and commercialization of tildacerfont in Japan, including the achievement of specified net sales thresholds, if approved. Kaken has agreed to pay the Company a non-creditable, non-refundable specified purchase price for each unit of Company-manufactured product supplied to Kaken for commercial sale. In addition, the Company will also be entitled to receive a royalty for each unit of non-Company manufactured product sold equal to a range of double-digit percentages up to the mid-twenties based on annual net sales of tildacerfont in Japan. Both the purchase price for each unit and the royalty rate are subject to reduction in certain circumstances as specified in the Kaken License Agreement. Kaken’s obligation to pay royalties will continue for ten years after the first commercial sale in Japan or, if later, until the expiration of regulatory exclusivity of tildacerfont or the expiration of the last valid claim of a Company-licensed patent covering tildacerfont in Japan.

The Company identified a combined performance obligation consisting of the license and know-how granted to Kaken as well as certain non-contingent research and development activities. The Company determined that the transaction price at the inception of the Kaken License Agreement consisted of the upfront payment of $15.0 million. The transaction price is recognized as revenue using the cost-based input method over the estimated period of its non-contingent research and development obligations, which is approximately two years.

During each of the three months ended March 31, 2024 and 2023, the Company recognized collaboration revenue of $2.0 million. As of March 31, 2024, deferred revenue was $2.9 million, all of which was current.

CONDENSED STATEMENT OF STOCKHOLDERS' EQUITY (Parenthetical) (Unaudited) $ in Thousands	3 Months Ended
	Mar. 31, 2023 USD ($)
Statement of Stockholders' Equity [Abstract]
offering costs	$ 2,721

Capital Structure

3 Months Ended

Mar. 31, 2024

Equity [Abstract]

Capital Structure

8. Capital Structure

Common Stock

As of March 31, 2024 and December 31, 2023, the Company was authorized to issue 200,000,000 shares of common stock $0.0001 par value per share. Holders of common stock are entitled to dividends if and when declared by the board of directors of the Company (“Board of Directors”). The holder of each share of common stock is entitled to one vote. As of March 31, 2024, no dividends were declared.

Shares reserved for future issuance

Common Stock reserved for future issuance, on an as converted basis, consisted of the following:


	March 31, 2024		December 31, 2023
Common stock warrants, issued and outstanding		12,687,000		12,687,000
Restricted and performance stock units, issued and outstanding		4,037,200		3,482,663
Stock options, issued and outstanding		3,869,873		4,097,376
Shares available for future issuance under 2020 Equity Incentive Plan		1,673,145		77,631
Shares available for future issuance under 2020 Employee Stock Purchase Plan		1,085,336		675,038
Total shares reserved		23,352,554		21,019,708

- Definition

The entire disclosure for equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
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+ Details

Stock-Based Compensation Expense - Additional Information (Details) - RSU	3 Months Ended
	Mar. 31, 2024 $ / shares shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
RSUs granted	1,698,400
Weighted Average Grant Date Fair Value Per Share \| $ / shares	$ 1.59
Number of RSUs outstanding	1,651,262
Probable of Achievement
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
RSUs granted	1,007,062
Clinical Development Milestones \| Share Based Compensation Award Tranche Four
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
RSUs granted	795,350

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details

Fair Value Measurements

3 Months Ended

Mar. 31, 2024

Fair Value Disclosures [Abstract]

Fair Value Measurements

3. Fair Value Measurements

Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability, or an exit price, in the principal or most advantageous market for that asset or liability in an orderly transaction between market participants on the measurement date. Fair value measurement establishes a fair value hierarchy that requires an entity to maximize the use of observable inputs, where available, and minimize the use of unobservable inputs when measuring fair value.

The Company determined the fair value of financial assets and liabilities using the fair value hierarchy that describes three levels of inputs that may be used to measure fair value, as follows:

Level 1 — Quoted prices in active markets for identical assets and liabilities;

Level 2 — Inputs other than Level 1 that are observable, either directly or indirectly, such as quoted prices for similar assets or liabilities, quoted prices in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities; and

Level 3 — Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities.

Assets and liabilities measured at fair value are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. The Company classifies money market funds and U.S. treasury securities as Level 1 investments as the Company uses quoted prices in active markets for identical assets to determine the fair value.

The following table summarizes the Company's financial assets measured at fair value on a recurring basis by level within the fair value hierarchy (in thousands):


		March 31, 2024
	Fair Value Hierarchy Level	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Money market funds	Level 1	$	79,985	$	—	$	—	$	79,985
Total cash equivalents		$	79,985	$	—	$	—	$	79,985


		December 31, 2023
	Fair Value Hierarchy Level	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Money market funds	Level 1	$	95,875	$	—	$	—	$	95,875
Total cash equivalents		$	95,875	$	—	$	—	$	95,875

There have been no realized gains or losses on available for sale securities for the periods presented. Unrealized gains and losses are included in “accumulated other comprehensive loss” within stockholders' equity on the condensed balance sheets.

There were no investments as of March 31, 2024 and December 31, 2023. No allowance for credit losses has been recognized as of March 31, 2024. During the three months ended March 31, 2024 and 2023, the Company did not recognize any impairment losses related to investments.

The estimated fair value of the term loan was $3.2 million and $3.6 million as of March 31, 2024 and December 31, 2023, respectively, and was based on market observable interest rates, a Level 2 input.

The Company did not have any financial liabilities recorded at fair value on a recurring or non-recurring basis as of March 31, 2024 and December 31, 2023.

- 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

Organization and Principal Activities - Additional Information (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended
	Feb. 28, 2023	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023	Feb. 28, 2022
Organization And Principal Activities [Line Items]
Cash, cash equivalents, and short-term investments		$ 81,200
Net loss		(11,625)	$ (12,791)
Cash in operations		15,000
Accumulated deficit		$ (208,857)		$ (197,232)
Shelf Registration And Sales Agreement
Organization And Principal Activities [Line Items]
Maximum amount of sale covered in shelf registration statement					$ 200,000
Jefferies LLC \| Shelf Registration And Sales Agreement
Organization And Principal Activities [Line Items]
Maximum amount of offering issuance and sale covered in sales agreement					$ 21,000
Private Placement [Member]
Organization And Principal Activities [Line Items]
Proceeds from Issuance of Private Placement	$ 53,600
Private Placement [Member] \| Common Stock
Organization And Principal Activities [Line Items]
Number of shares issued	16,116,000
Private Placement [Member] \| Pre Funded Warrants
Organization And Principal Activities [Line Items]
Number of warrants issued	800,000
Private Placement [Member] \| Standard Warrants
Organization And Principal Activities [Line Items]
Number of warrants issued	12,687,000

Capital Structure (Tables)

3 Months Ended

Mar. 31, 2024

Equity [Abstract]

Summary of Common Stock Reserved for Future Issuance

Common Stock reserved for future issuance, on an as converted basis, consisted of the following:


	March 31, 2024		December 31, 2023
Common stock warrants, issued and outstanding		12,687,000		12,687,000
Restricted and performance stock units, issued and outstanding		4,037,200		3,482,663
Stock options, issued and outstanding		3,869,873		4,097,376
Shares available for future issuance under 2020 Equity Incentive Plan		1,673,145		77,631
Shares available for future issuance under 2020 Employee Stock Purchase Plan		1,085,336		675,038
Total shares reserved		23,352,554		21,019,708

Capital Structure - Summary of Common Stock Reserved for Future Issuance (Details) - shares	Mar. 31, 2024	Dec. 31, 2023
Class Of Stock [Line Items]
Shares reserved for future issuance	23,352,554	21,019,708
Shares available for future issuance under 2020 Employee Stock Purchase Plan
Class Of Stock [Line Items]
Shares reserved for future issuance	1,085,336	675,038
Common Stock Warrants, issued and outstanding
Class Of Stock [Line Items]
Shares reserved for future issuance	12,687,000	12,687,000
Stock Options, Issued and Outstanding
Class Of Stock [Line Items]
Shares reserved for future issuance	3,869,873	4,097,376
Restricted and Performance Stock Units, Issued and Outstanding [Member]
Class Of Stock [Line Items]
Shares reserved for future issuance	4,037,200	3,482,663
Shares available for future issuance under 2020 Equity Incentive Plan
Class Of Stock [Line Items]
Shares reserved for future issuance	1,673,145	77,631

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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+ Details

Leases

3 Months Ended

Mar. 31, 2024

Leases [Abstract]

Leases

5. Leases

The Company leases space under a non-cancelable operating lease, which requires the Company to pay base rent, real estate taxes, insurance, general repairs, and maintenance. In December 2022, the Company entered into a non-cancelable operating lease for approximately 6,500 square feet of office space in South San Francisco, California, which commenced in December 2022 and expires in February 2028 (the “South San Francisco Lease”). The Company has an option to extend the lease term of the South San Francisco Lease for an additional three years which has not been included in the lease term as it is not reasonably certain that the Company will exercise this option.

CONDENSED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Income Statement [Abstract]
Collaboration revenue	$ 2,002	$ 1,964
Operating expenses:
Research and development	10,317	11,712
General and administrative	4,318	3,451
Total operating expenses	14,635	15,163
Loss from operations	(12,633)	(13,199)
Interest expense	(97)	(131)
Interest income and other expense, net	1,105	539
Net loss	(11,625)	(12,791)
Other comprehensive gain, net of tax:
Unrealized gain on available for sale securities	0	370
Total comprehensive loss	$ (11,625)	$ (12,421)
Net loss per share, basic	$ (0.28)	$ (0.4)
Net loss per share, diluted	$ (0.28)	$ (0.4)
Weighted-average shares of common stock outstanding, basic	41,096,231	31,900,160
Weighted-average shares of common stock outstanding, diluted	41,096,231	31,900,160

Net Loss Per Share (Tables)

3 Months Ended

Mar. 31, 2024

Earnings Per Share [Abstract]

Schedule of Computation of Basic and Diluted Net Loss Per Share

The following table sets forth the computation of the basic and diluted net loss per share (in thousands, except share and per share amounts):


	Three Months Ended March 31,
	2024			2023
Numerator:
Net loss	$	(11,625	)	$	(12,791	)
Denominator:
Weighted-average shares of Common Stock outstanding		41,096,231			31,900,160
Net loss per share, basic and diluted	$	(0.28	)	$	(0.40	)

Schedule of Potentially Dilutive Securities not Included in Calculation of Diluted Per Share

Basic net loss per share was the same as diluted net loss per share for all periods as the inclusion of potentially dilutive securities would have been anti-dilutive. Potentially dilutive securities that were not included in the diluted per share calculations were as follows:


	March 31,
	2024		2023
Shares subject to outstanding Standard Warrants		12,687,000		12,687,000
Shares subject to outstanding RSUs		4,037,200		2,373,915
Shares subject to outstanding common stock options		3,869,873		4,045,310
Estimated shares issuable under the 2020 Employee Stock Purchase Plan		107,634		336,704
Total		20,701,707		19,442,929

Term Loan (Tables)

3 Months Ended

Mar. 31, 2024

Debt Disclosure [Abstract]

Schedule of Future Principal Payments

As of March 31, 2024, future payments of principal and interest are as follows (in thousands):


Year ending December 31,
2024 (remaining 9 months)	$	1,384
2025		1,714
2026		136
Total	$	3,234
Less: interest		(260	)
Term loan, gross	$	2,974
Less: unamortized debt issuance costs		(31	)
Less: term loan, current portion		(1,622	)
Term loan, net of current portion	$	1,321

Net Loss Per Share - Schedule of Computation of Basic and Diluted Net Loss Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Numerator:
Net loss	$ (11,625)	$ (12,791)
Denominator:
Weighted-average shares of Common Stock outstanding, basic	41,096,231	31,900,160
Weighted-average shares of Common Stock outstanding, diluted	41,096,231	31,900,160
Net loss per share, basic	$ (0.28)	$ (0.4)
Net loss per share, diluted	$ (0.28)	$ (0.4)

- Definition

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

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- Definition

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-Section S99
-Paragraph 1B
-Subparagraph (SX 210.13-02(a)(5))
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Reference 30: http://www.xbrl.org/2003/role/disclosureRef
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Reference 31: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Balance Sheet Components

3 Months Ended

Mar. 31, 2024

Balance Sheet Components Disclosure [Abstract]

Balance Sheet Components

4. Balance Sheet Components

Accrued Expenses and Other Current Liabilities

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


	March 31, 2024		December 31, 2023
Accrued research and development expenses	$	8,948	$	10,832
Accrued compensation and benefits		1,586		3,101
Accrued general and administrative expenses		1,180		416
Lease liabilities, current portion		259		251
Total accrued expenses and other current liabilities	$	11,973	$	14,600

Accrued research and development expenses were primarily related to clinical trials and manufacturing of clinical drug supply.

Term Loan - Additional Information (Details) $ / shares in Units, $ in Thousands	1 Months Ended		3 Months Ended
	Nov. 30, 2020 shares	Sep. 30, 2019 USD ($) $ / shares shares	Mar. 31, 2024 USD ($) Installment	Dec. 31, 2023	Dec. 31, 2022 USD ($)
Debt Instrument [Line Items]
Aggregate principal amount			$ 3,234
Carrying value of the Term Loan			2,974
Term Loan \| Silicon Valley Bank
Debt Instrument [Line Items]
Aggregate principal amount		$ 4,500
Amount of total debt available			$ 30,000
Interest rate of term loan			9.00%	9.00%
Debt instrument, maturity date			Jan. 01, 2026
Number of monthly installments \| Installment			37
Carrying value of the Term Loan			$ 2,900
Unamortized debt discount and issuance costs			$ 31
Term Loan \| Silicon Valley Bank \| Warrant
Debt Instrument [Line Items]
Number of shares issuable upon the exercise of warrant \| shares		49,609
Warrants exercise price \| $ / shares		$ 1.44
Estimated fair value of the warrant		$ 100
Term Loan \| Silicon Valley Bank \| Maximum
Debt Instrument [Line Items]
Debt instrument prepayment fee percentage			2.00%
Term Loan \| Silicon Valley Bank \| Minimum
Debt Instrument [Line Items]
Debt instrument prepayment fee percentage			1.00%
Term Loan \| Common Stock \| Silicon Valley Bank \| Warrant
Debt Instrument [Line Items]
Net exercised of common stock \| shares	46,358
First Tranche Term Loan \| Silicon Valley Bank
Debt Instrument [Line Items]
Amount of debt available under the first tranche			$ 20,000
End of term payment, amount			$ 300
End of term payment, percentage			6.00%
Debt issuance costs			$ 3,000
Second Tranche Term Loan
Debt Instrument [Line Items]
Commitments					$ 10,000
Second Tranche Term Loan \| Silicon Valley Bank
Debt Instrument [Line Items]
Amount of debt available under the second tranche			$ 10,000
Debt instrument, maturity date			Dec. 31, 2022
Second Tranche Term Loan \| Silicon Valley Bank \| Prime Rate
Debt Instrument [Line Items]
Floating interest scenario two			3.75%
Second Tranche Term Loan \| Silicon Valley Bank \| Prime Rate \| Maximum
Debt Instrument [Line Items]
Floating interest scenario one			0.50%

Fair Value Measurements (Tables)

3 Months Ended

Mar. 31, 2024

Fair Value Disclosures [Abstract]

Summary of Financial Assets Measured at Fair Value on Recurring Basis

The following table summarizes the Company's financial assets measured at fair value on a recurring basis by level within the fair value hierarchy (in thousands):


		March 31, 2024
	Fair Value Hierarchy Level	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Money market funds	Level 1	$	79,985	$	—	$	—	$	79,985
Total cash equivalents		$	79,985	$	—	$	—	$	79,985


		December 31, 2023
	Fair Value Hierarchy Level	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Money market funds	Level 1	$	95,875	$	—	$	—	$	95,875
Total cash equivalents		$	95,875	$	—	$	—	$	95,875

CONDENSED BALANCE SHEETS (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Current assets:
Cash and cash equivalents	$ 81,154	$ 96,339
Prepaid expenses	3,100	3,876
Other current assets	1,611	1,968
Total current assets	85,865	102,183
Right-of-use assets	1,121	1,181
Other assets	553	582
Total assets	87,539	103,946
Current liabilities:
Accounts payable	1,891	3,332
Accrued expenses and other current liabilities	11,973	14,600
Term loan, current portion	1,622	1,622
Deferred revenue	2,908	4,911
Total current liabilities	18,394	24,465
Lease liabilities, net of current portion	950	1,019
Term loan, net of current portion	1,321	1,717
Other liabilities	250	236
Total liabilities	20,915	27,437
Commitments and contingencies
Stockholders’ equity:
Preferred stock, $0.0001 par value; 10,000,000 shares authorized and no shares issued or outstanding as of March 31, 2024 and December 31, 2023	0	0
Common stock, $0.0001 par value; 200,000,000 shares authorized as of March 31, 2024 and December 31, 2023; 41,154,799 and 41,029,832 shares issued and outstanding as of March 31, 2024 and December 31, 2023, respectively	4	4
Additional paid-in capital	275,477	273,737
Accumulated deficit	(208,857)	(197,232)
Total stockholders equity	66,624	76,509
Total liabilities and stockholders’ equity	$ 87,539	$ 103,946

Balance Sheet Components (Tables)

3 Months Ended

Mar. 31, 2024

Balance Sheet Components Disclosure [Abstract]

Schedule of Accrued Expenses and Other Current Liabilities

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


	March 31, 2024		December 31, 2023
Accrued research and development expenses	$	8,948	$	10,832
Accrued compensation and benefits		1,586		3,101
Accrued general and administrative expenses		1,180		416
Lease liabilities, current portion		259		251
Total accrued expenses and other current liabilities	$	11,973	$	14,600

CONDENSED STATEMENT OF STOCKHOLDERS' EQUITY (Unaudited) - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Gain/(Loss)	Accumulated Deficit
Balance at Dec. 31, 2022	$ 68,486	$ 3	$ 218,354	$ (558)	$ (149,313)
Balance, Shares at Dec. 31, 2022		23,601,004
Issuance of common stock related to vesting of restricted stock units, net of tax withholdings	(23)		(23)
Issuance of common stock related to vesting of restricted stock units, net of tax withholdings, shares		29,112
Issuance of common stock and warrants, net of offering costs, shares		16,116,000
Issuance of common stock and warrants, net of offering costs	50,895	$ 1	50,894
Stock-based compensation	1,060		1,060
Unrealized gain on available for sale securities	370			370
Net loss	(12,791)				(12,791)
Balance at Mar. 31, 2023	107,997	$ 4	270,285	$ (188)	(162,104)
Balance, Shares at Mar. 31, 2023		39,746,116
Balance at Dec. 31, 2023	$ 76,509	$ 4	273,737		(197,232)
Balance, Shares at Dec. 31, 2023	41,029,832	41,029,832
Exercise of common stock options	$ 180		180
Exercise of common stock options, Shares		120,328
Issuance of common stock related to vesting of restricted stock units, net of tax withholdings	(2)		(2)
Issuance of common stock related to vesting of restricted stock units, net of tax withholdings, shares		4,639
Stock-based compensation	1,562		1,562
Unrealized gain on available for sale securities	0
Net loss	(11,625)				(11,625)
Balance at Mar. 31, 2024	$ 66,624	$ 4	$ 275,477		$ (208,857)
Balance, Shares at Mar. 31, 2024	41,154,799	41,154,799

Document and Entity Information - shares	3 Months Ended
Document and Entity Information - shares	Mar. 31, 2024	May 09, 2024
Cover [Abstract]
Entity Registrant Name	Spruce Biosciences, Inc.
Entity Central Index Key	0001683553
Document Type	10-Q
Document Period End Date	Mar. 31, 2024
Trading Symbol	SPRB
Amendment Flag	false
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	Q1
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding		41,154,799
Entity Shell Company	false
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Small Business	true
Entity File Number	001-39594
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	81-2154263
Entity Address, Address Line One	611 Gateway Boulevard
Entity Address, Address Line Two	Suite 740
Entity Address, City or Town	South San Francisco
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94080
City Area Code	415
Local Phone Number	655-4168
Document Quarterly Report	true
Document Transition Report	false
Title of 12(b) Security	Common Stock, par value $0.0001 per share
Security Exchange Name	NASDAQ

Balance Sheet Components - Schedule of Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Balance Sheet Components Disclosure [Abstract]
Accrued research and development expenses	$ 8,948	$ 10,832
Accrued compensation and benefits	1,586	3,101
Accrued general and administrative expenses	1,180	416
Lease liabilities, current portion	259	251
Total accrued expenses and other current liabilities	$ 11,973	$ 14,600

Summary of Significant Accounting Policies (Policies)	3 Months Ended
Summary of Significant Accounting Policies (Policies)	Mar. 31, 2024
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) and applicable rules and regulations of the SEC for interim reporting. As permitted under those rules and regulations, certain notes or other financial information normally included in financial statements prepared in accordance with U.S. GAAP have been condensed or omitted. The condensed balance sheet as of March 31, 2024, the condensed statements of operations and comprehensive loss for the three months ended March 31, 2024 and 2023, the condensed statement of stockholders’ equity for the three months ended March 31, 2024 and 2023, and the condensed statements of cash flows for the three months ended March 31, 2024 and 2023 are unaudited. The interim condensed financial statements have been prepared on the same basis as the annual financial statements and, in the opinion of management, reflect all adjustments, which include only normal, recurring adjustments that are necessary to present fairly the Company’s results for the interim periods presented. The condensed balance sheet as of December 31, 2023 is derived from the Company’s audited financial statements. The results of operations for the three months ended March 31, 2024 are not necessarily indicative of the results to be expected for the year ending December 31, 2024, or for any other future annual or interim period. These interim condensed financial statements should be read in conjunction with the Company’s Annual Report on Form 10-K for the year ended December 31, 2023 filed with the SEC on March 18, 2024 (“Annual Report”).
Use of Estimates	Use of Estimates 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, liabilities and expenses as well as related disclosure of contingent assets and liabilities. Significant estimates and assumptions reflected in these financial statements include, but are not limited to, accrued research and development expenses, revenue recognition, stock-based compensation, and uncertain tax positions. The Company bases its estimates on its historical experience and on assumptions that it believes are reasonable; however, actual results could significantly differ from those estimates.
Risks and Uncertainties	Risks and Uncertainties Any product candidates developed by the Company will require approvals from the U.S. Food and Drug Administration or foreign regulatory agencies prior to commercial sales. There can be no assurance that the Company’s current and future product candidates will meet desired efficacy and safety requirements to obtain the necessary approvals. If approval is denied or delayed, it may have a material adverse impact on the Company’s business and its financial statements. The Company is subject to a number of risks similar to other late-stage biopharmaceutical companies including, but not limited to, dependency on the clinical success of the Company’s product candidate, tildacerfont, ability to obtain regulatory approval of tildacerfont, the need for substantial additional financing to achieve its goals, uncertainty of broad adoption of its approved products, if any, by physicians and consumers, significant competition, untested manufacturing capabilities, and dependence on key individuals and sole source suppliers. Global economic and business activities continue to face widespread macroeconomic and geopolitical uncertainties, including recent and potential future disruptions in access to bank deposits or lending commitments due to bank failures, labor shortages, inflation and monetary supply shifts, recession risks and potential disruptions from the ongoing wars in Ukraine and Israel and related sanctions. The Company continues to actively monitor the impact of these macroeconomic and geopolitical factors on its financial condition, liquidity, operations, and workforce. The extent of the impact of these factors on the Company’s operational and financial performance, including its ability to execute its business strategies and initiatives in the expected time frame, will depend on future developments, which are uncertain and cannot be predicted; however, any continued or renewed disruption resulting from these factors could negatively impact the Company’s business.
Concentration of Credit Risk	Concentration of Credit Risk Financial instruments, which potentially subject the Company to significant concentration of credit risk, consist primarily of cash and cash equivalents. The Company maintains deposits in federally insured financial institutions in excess of federally insured limits. The Company is exposed to credit risk in the event of default by the financial institutions holding its cash and cash equivalents to the extent recorded in the condensed balance sheets.
Significant Accounting Policies	Significant Accounting Policies There have been no significant changes to the significant accounting policies during the three months ended March 31, 2024, as compared to the significant accounting policies described in the Annual Report.
Emerging Growth Company Status	Emerging Growth Company Status The Company is an emerging growth company as defined in the Jumpstart Our Business Startups Act of 2012 (“JOBS Act”) and may take advantage of reduced reporting requirements that are otherwise applicable to public companies. Section 107 of the JOBS Act exempts emerging growth companies from being required to comply with new or revised financial accounting standards until private companies are required to comply with those standards. The Company has elected to use the extended transition period for complying with new or revised accounting standards.
Recent Accounting Pronouncements - Not Yet Adopted	Recent Accounting Pronouncements - Not Yet Adopted In December 2023, the FASB issued Accounting Standards Update 2023-09, Income Taxes - Improvements to Income Tax Disclosures (“ASU 2023-09”) requiring enhancements and further transparency to certain income tax disclosures, most notably the tax rate reconciliation and income taxes paid. ASU 2023-09 is effective for fiscal years beginning after December 15, 2024 on a prospective basis and retrospective application is permitted. The Company is currently evaluating the impact of the adoption of this standard on the Company’s financial statements and related disclosures. In November 2023, the FASB issued ASU 2023-07, Improvements to Reportable Segment Disclosures (“ASU 2023-07”) which is intended to improve reportable segment disclosure requirements, primarily through additional disclosures about significant segment expenses, including for single reportable segment entities. The standard is effective for fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024, with early adoption permitted. The amendments should be applied retrospectively to all prior periods presented in the financial statements. The Company is currently evaluating the disclosure requirements related to the new standard.

Stock-Based Compensation Expense (Tables)

3 Months Ended

Mar. 31, 2024

Share-Based Payment Arrangement [Abstract]

Summary of Stock-Based Compensation Expense

The following table summarizes the components of stock-based compensation expense recognized in the Company’s condensed statements of operations and comprehensive loss during the three months ended March 31, 2024 and 2023 (in thousands):


	Three Months Ended March 31,
	2024		2023
Research and development	$	579	$	284
General and administrative		983		776
Total stock-based compensation expense	$	1,562	$	1,060

Capital Structure - Additional Information (Details) - USD ($)	3 Months Ended
	Mar. 31, 2024	Dec. 31, 2023
Class Of Stock [Line Items]
Common stock shares authorized	200,000,000	200,000,000
Common stock, par value	$ 0.0001	$ 0.0001
Common stockholders voting rights	one vote
Common stock dividends declared	$ 0

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

+ Details

Fair Value Measurements - Additional Information (Details) - USD ($)	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Allowance for credit losses	$ 0
Investments	0		$ 0
Estimated fair value of term loan	3,200,000		3,600,000
Debt securities, available-for-sale, realized gain (loss)	0
Debt securities, available-for-sale, realized gain (loss), excluding other-than-temporary impairment	0	$ 0
Fair Value Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Liabilities fair value	$ 0
Fair Value Non-recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Liabilities fair value			$ 0

Net Loss Per Share

3 Months Ended

Mar. 31, 2024

Earnings Per Share [Abstract]

Net Loss Per Share

10. Net Loss Per Share

The following table sets forth the computation of the basic and diluted net loss per share (in thousands, except share and per share amounts):


	Three Months Ended March 31,
	2024			2023
Numerator:
Net loss	$	(11,625	)	$	(12,791	)
Denominator:
Weighted-average shares of Common Stock outstanding		41,096,231			31,900,160
Net loss per share, basic and diluted	$	(0.28	)	$	(0.40	)


	March 31,
	2024		2023
Shares subject to outstanding Standard Warrants		12,687,000		12,687,000
Shares subject to outstanding RSUs		4,037,200		2,373,915
Shares subject to outstanding common stock options		3,869,873		4,045,310
Estimated shares issuable under the 2020 Employee Stock Purchase Plan		107,634		336,704
Total		20,701,707		19,442,929

Stock-Based Compensation Expense - Summary of Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 1,562	$ 1,060
Research and Development
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation expense	579	284
General and Administrative
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 983	$ 776

CONDENSED BALANCE SHEETS (Parenthetical) (Unaudited) - $ / shares	Mar. 31, 2024	Dec. 31, 2023
Statement of Financial Position [Abstract]
Preferred Stock, Par Value	$ 0.0001	$ 0.0001
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares issued	41,154,799	41,029,832
Common stock, shares outstanding	41,154,799	41,029,832

CONDENSED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Cash flows from operating activities
Net loss	$ (11,625)	$ (12,791)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation expense	1,562	1,060
Depreciation and amortization	15	19
Net accretion of discount on available-for-sale securities	0	(183)
Non-cash lease expense	60	58
Loss on disposal of property and equipment	0	2
Changes in operating assets and liabilities:
Accounts receivable	0	(15,000)
Prepaid expenses and other current assets	(191)	664
Other assets	74	157
Accounts payable	(1,441)	2,022
Accrued expenses and other current liabilities	(1,354)	(793)
Deferred revenue	(2,003)	13,036
Other liabilities	(55)	(41)
Net cash used in operating activities	(14,958)	(11,790)
Cash flows from investing activities
Proceeds from maturities of investments	0	22,365
Purchase of investments	0	(11,881)
Net cash provided by investing activities	0	10,484
Cash flows from financing activities
Proceeds from issuance of common stock and warrants	0	53,616
Proceeds from exercise of common stock options	180	0
Payment of offering costs	0	(2,659)
Repayment of term loan	(405)	(405)
Tax withholding payments on restricted stock units	(2)	(23)
Net cash (used in) provided by financing activities	(227)	50,529
Net (decrease) increase in cash, cash equivalents, and restricted cash	(15,185)	49,223
Cash, cash equivalents, and restricted cash at beginning of period	96,374	24,732
Cash, cash equivalents, and restricted cash at end of period	81,189	73,955
Reconciliation of cash, cash equivalents, and restricted cash
Cash and cash equivalents	81,154	73,926
Restricted cash, long-term (included in other assets)	35	29
Total cash, cash equivalents and restricted cash	$ 81,189	$ 73,955

Stock-Based Compensation Expense

3 Months Ended

Mar. 31, 2024

Share-Based Payment Arrangement [Abstract]

Stock-Based Compensation Expense

9. Stock-Based Compensation Expense


	Three Months Ended March 31,
	2024		2023
Research and development	$	579	$	284
General and administrative		983		776
Total stock-based compensation expense	$	1,562	$	1,060

Restricted Stock Units

During the three months ended March 31, 2024, the Company granted 1,698,400 restricted stock units (“RSUs”) with a weighted-average grant date fair value of $1.59 per unit. RSU grants in the period included 795,350 RSUs subject to performance-based vesting conditions related to the satisfaction of certain clinical development milestones. As of March 31, 2024, the Company had 1,651,262 RSUs outstanding subject to performance-based vesting conditions, of which 1,007,062 RSUs are considered probable of achievement.

Net Loss Per Share - Schedule of Potentially Dilutive Securities not Included in Calculation of Diluted Per Share (Details) - shares	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potential dilutive securities excluded from diluted net loss per share	20,701,707	19,442,929
Shares subject to outstanding Standard Warrants
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potential dilutive securities excluded from diluted net loss per share	12,687,000	12,687,000
Shares subject to outstanding RSUs
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potential dilutive securities excluded from diluted net loss per share	4,037,200	2,373,915
Shares subject to outstanding common stock options
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potential dilutive securities excluded from diluted net loss per share	3,869,873	4,045,310
Estimated shares issuable under the 2020 Employee Stock Purchase Plan
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potential dilutive securities excluded from diluted net loss per share	107,634	336,704