0000950170-24-009809 | 10-K | XBRL Viewer

Equity Financings	12 Months Ended
Dec. 31, 2023
Equity [Abstract]
Equity Financings	(7) Equity Financings At the Market Equity Financing On July 22, 2020, the Company entered into a Capital on Demand TM Sales Agreement (the Sales Agreement) with JonesTrading Institutional Services LLC, as agent (JonesTrading), pursuant to which the Company may offer and sell, from time to time through JonesTrading, shares of the Company’s common stock, par value $0.001 per share (the Common Stock), having an aggregate offering price of up to $54.0 million (the Shares). Under the Sales Agreement, JonesTrading may sell the Shares by any method permitted by law and deemed to be an “at the market offering” as defined in Rule 415 promulgated under the Securities Act of 1933, as amended, including sales made directly on or through the Nasdaq Capital Market, on any other existing trading market for the Common Stock or to or through a market maker. In addition, under the amended Sales Agreement, JonesTrading may sell the Shares by any other method permitted by law, including in negotiated transactions. The Company may instruct JonesTrading not to sell Shares if the sales cannot be effected at or above the price designated by the Company from time to time. The Company is not obligated to make any sales of the Shares under the Sales Agreement. The offering of Shares pursuant to the Sales Agreement will terminate upon the earlier of (a) the sale of all of the Shares subject to the Sales Agreement or (b) the termination of the Sales Agreement by JonesTrading or the Company, as permitted therein. The Company paid JonesTrading a commission rate equal to 3.0% of the aggregate gross proceeds from each sale of Shares and agreed to provide JonesTrading with customary indemnification and contribution rights. The Company will also reimburse JonesTrading for certain specified expenses in connection with entering into the Sales Agreement. No sales were made in 2023 or 2022. In April 2021, the Company amended the 2020 Sales Agreement and the amount available for the offering under its prospectus to the Company’s registration statement on Form S-3 (No. 333-254585). The amount available for the offering under the prospectus supplement is subject to the limitation of not selling a total value amount of shares exceeding more than one-third of the Company’s public float in any 12-month period.

Equity Financings

12 Months Ended

Dec. 31, 2023

(7) Equity Financings

At the Market Equity Financing

On July 22, 2020, the Company entered into a Capital on Demand TM Sales Agreement (the Sales Agreement) with JonesTrading Institutional Services LLC, as agent (JonesTrading), pursuant to which the Company may offer and sell, from time to time through JonesTrading, shares of the Company’s common stock, par value $0.001 per share (the Common Stock), having an aggregate offering price of up to $54.0 million (the Shares).

Under the Sales Agreement, JonesTrading may sell the Shares by any method permitted by law and deemed to be an “at the market offering” as defined in Rule 415 promulgated under the Securities Act of 1933, as amended, including sales made directly on or through the Nasdaq Capital Market, on any other existing trading market for the Common Stock or to or through a market maker. In addition, under the amended Sales Agreement, JonesTrading may sell the Shares by any other method permitted by law, including in negotiated transactions. The Company may instruct JonesTrading not to sell Shares if the sales cannot be effected at or above the price designated by the Company from time to time.

The Company is not obligated to make any sales of the Shares under the Sales Agreement. The offering of Shares pursuant to the Sales Agreement will terminate upon the earlier of (a) the sale of all of the Shares subject to the Sales Agreement or (b) the termination of the Sales Agreement by JonesTrading or the Company, as permitted therein.

The Company paid JonesTrading a commission rate equal to 3.0% of the aggregate gross proceeds from each sale of Shares and agreed to provide JonesTrading with customary indemnification and contribution rights. The Company will also reimburse JonesTrading for certain specified expenses in connection with entering into the Sales Agreement.

No sales were made in 2023 or 2022.

In April 2021, the Company amended the 2020 Sales Agreement and the amount available for the offering under its prospectus to the Company’s registration statement on Form S-3 (No. 333-254585). The amount available for the offering under the prospectus supplement is subject to the limitation of not selling a total value amount of shares exceeding more than one-third of the Company’s public float in any 12-month period.

- Definition

The entire disclosure for equity.

+ References

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+ Details

Income Taxes (Details Textual) - USD ($)	12 Months Ended
Income Taxes (Details Textual) - USD ($)	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2017
Income Tax [Line Items]
Net operating loss carryforwards	$ 208,100,000
Tax Credit Carryforward, Description	The net operating loss carryforwards beginning in 2018, have no expiration.
Valuation allowance	$ 55,500,000
Increase in net deferred tax assets and liabilities	$ 1,200,000
Federal statutory income tax rate	21.00%	21.00%
Reserve for uncertain tax positions	$ 0	$ 0
Interest or penalties recognized	$ 0	$ 0
Open tax year	2009
Research Tax Credit Carryforward
Income Tax [Line Items]
Research and experimentation credits	$ 2,400,000
Operating loss carryforwards, limitations on use	Utilization of net operating losses and tax credits, including those acquired as a result of the Merger, will be subject to an annual limitation due to ownership change limitations provided by Internal Revenue Code Section 382. The Company believes that an ownership change limitation as defined under Section 382 of the U.S. Internal Revenue Code occurred as a result of its various historical financing transactions. Future utilization of the federal net operating losses and tax credit carryforwards accumulated from June 2005 to the change in ownership date will be subject to annual limitations to offset future taxable income. The annual limitation
Tax credit carryforward, limitations on use	Utilization of net operating losses and tax credits, including those acquired as a result of the Merger, will be subject to an annual limitation due to ownership change limitations provided by Internal Revenue Code Section 382. The Company believes that an ownership change limitation as defined under Section 382 of the U.S. Internal Revenue Code occurred as a result of its various historical financing transactions. Future utilization of the federal net operating losses and tax credit carryforwards accumulated from June 2005 to the change in ownership date will be subject to annual limitations to offset future taxable income. The annual limitation may result in the expiration of the net operating losses and credits before utilization. As such, a portion of the Company’s net operating loss carryforwards may be limited.
Earliest Tax Year
Income Tax [Line Items]
Operating loss carryforwards expiration year			2025
Latest Tax Year
Income Tax [Line Items]
Operating loss carryforwards expiration year			2037

The Company and Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2023
Accounting Policies [Abstract]
Description of Business	Description of Business ARCA biopharma, Inc. (the Company or ARCA), a Delaware corporation, is headquartered in Westminster, Colorado. The Company is a clinical-stage biopharmaceutical company applying a precision medicine approach to the development and commercialization of genetically targeted therapies for cardiovascular diseases. The Company’s lead product candidate is Gencaro™ (bucindolol hydrochloride) for the treatment of atrial fibrillation (AF) in patients with chronic heart failure (HF). In April 2022, the Board of Directors established a Special Committee and, in May 2022, retained Ladenburg Thalmann & Co. Inc. to evaluate strategic options, including transactions involving a merger, sale of all or part of the Company’s assets, or other alternatives with the goal of maximizing stockholder value. The Company does not have a defined timeline for the strategic review process and the review may not result in any specific action or transaction.
Liquidity and Going Concern	Liquidity and Going Concern The Company devotes substantially all of its efforts towards obtaining regulatory approval and raising capital necessary to fund its operations and it is subject to a number of risks associated with clinical research and development, including dependence on key individuals, the development of and regulatory approval of commercially viable products, the need to raise adequate additional financing necessary to fund the development and commercialization of its products, and competition from larger companies. The Company has not generated revenue to date and has incurred substantial losses and negative cash flows from operations since its inception. The Company has historically funded its operations through issuances of common and preferred stock. The Company believes that its current cash and cash equivalents as of December 31, 2023 will be sufficient to fund its operations through the middle of fiscal year 2025. The Company's review of its strategic options may impact this projection. Changing circumstances may cause us to consume capital significantly faster or slower than currently anticipated. The Company has based these estimates on assumptions that may prove to be wrong, and the Company could exhaust its available financial resources sooner than the Company currently anticipates. Therefore, the Company will have to raise additional capital for clinical trials of Gencaro. The Company may not be able to raise sufficient capital on acceptable terms, or at all, to continue development of Gencaro or rNAPc2 or to otherwise continue operations and may not be able to execute any strategic transaction. The Company’s liquidity, and its ability to raise additional capital or complete any strategic transaction, depends on a number of factors, including, but not limited to, the following: • the costs and timing for the potential additional clinical trials in order to gain possible regulatory approval for Gencaro, rNAPc2, or any other product candidate; • the market price of the Company’s stock and the availability and cost of additional equity capital from existing and potential new investors; • the Company’s ability to retain the listing of its common stock on the Nasdaq Capital Market; • general economic and industry conditions affecting the availability and cost of capital, including as a result of deteriorating market conditions due to investor concerns regarding inflation, adverse developments affecting the financial services industry, continued hostilities between Russia and Ukraine and Hamas’ attack against Israel and the ensuing conflict; • the Company’s ability to control costs associated with its operations; • the costs of filing, prosecuting, defending and enforcing any patent claims and other intellectual property rights; and • the terms and conditions of the Company’s existing collaborative and licensing agreements. The sale of additional equity or convertible debt securities would likely result in substantial additional dilution to the Company’s stockholders. If the Company raises additional funds through the incurrence of indebtedness, the obligations related to such indebtedness would be senior to rights of holders of the Company’s capital stock and could contain covenants that would restrict the Company’s operations. The Company also cannot predict what consideration might be available, if any, to the Company or its stockholders, in connection with any strategic transaction. Should strategic alternatives or additional capital not be available to the Company, or not be available on acceptable terms, the Company may be unable to realize value from its assets and discharge its liabilities in the normal course of business which may, among other alternatives, cause the Company to further delay, substantially reduce or discontinue operational activities to conserve its cash resources.
Basis of Presentation	Basis of Presentation The accompanying financial statements have been prepared in accordance with U.S. generally accepted accounting principles (U.S. GAAP) and include all adjustments necessary for the fair presentation of our financial position, results of operations and cash flows for the periods presented. Management has performed an evaluation of the Company’s activities through the date of filing of this Annual Report on Form 10-K.
Recent Accounting Pronouncements	Recent Accounting Pronouncements The Company reviewed all other recently issued accounting pronouncements and concluded that they were either not applicable or not expected to have a significant impact to the financial statements.
Accounting Estimates in the Preparation of Financial Statements	Accounting Estimates in the Preparation of Financial Statements The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reporting period. The Company bases estimates on various assumptions that are believed to be reasonable under the circumstances. The Company believes significant judgment was involved in estimating the outsourcing expenses, and in estimating other accrued liabilities and income taxes. Management is continually evaluating and updating these estimates, and it is possible that these estimates will change in the future or that actual results may differ from these estimates.
Cash Equivalents	Cash Equivalents Cash equivalents generally consist of money market funds and debt securities with maturities of 90 days or less at the time of purchase. The Company invests its excess cash in securities with strong ratings and has established guidelines relative to diversification and maturity with the objective of maintaining safety of principal and liquidity.
Concentrations of Credit Risk	Concentrations of Credit Risk Financial instruments that potentially subject the Company to significant concentrations of credit risk consist primarily of cash and cash equivalents. The Company has no off-balance-sheet concentrations of credit risk, such as foreign exchange contracts, option contracts, or foreign currency hedging arrangements. The Company maintains cash and cash equivalent balances in the form of bank demand deposits and money market fund accounts with financial institutions that management believes are creditworthy. Such balances may at times exceed the insured amount.
Property and Equipment	Property and Equipment Property and equipment are stated at cost less accumulated depreciation and amortization. Cost includes expenditures for equipment, leasehold improvements, replacements, and renewals. Maintenance and repairs are charged to expense as incurred. When assets are sold, retired, or otherwise disposed of, the cost and accumulated depreciation are removed from the accounts and any resulting gain or loss is reflected in operations. The cost of property and equipment is depreciated using the straight-line method over the estimated useful lives of the related assets. Leasehold improvements are amortized over the shorter of the life of the lease or the estimated useful life of the assets.
Comprehensive Loss	Comprehensive Loss Comprehensive loss is defined as the change in equity during a period from transactions and other events and/or circumstances from non-owner sources. If the Company had comprehensive gains (losses), they would be reflected in the statement of operations and comprehensive loss and as a separate component in the statement of stockholders’ equity. There were no elements of comprehensive loss during the years ended December 31, 2023 and 2022.
Leases	Leases The Company determines if an arrangement is a lease at inception. Operating leases are included in right-of-use (ROU) asset – operating and lease obligations are included in accrued expenses and other liabilities and operating lease liability on the Company’s December 31, 2023 and 2022 balance sheets. ROU lease assets represent the Company’s right to use an underlying asset for the lease term and lease obligations represent the Company’s obligation to make lease payments arising from the lease. Operating ROU lease assets are recognized at the commencement date based on the present value of lease payments over the lease term. As the Company’s lease does not provide an implicit rate, the Company uses its incremental borrowing rate based on the information available at the commencement date in determining the present value of lease payments. The Company’s lease terms may include options to extend or terminate the lease when it is reasonably certain that the Company will exercise that option. Lease expense for lease payments is recognized on a straight-line basis over the lease term.
Accrued Outsourcing Expenses	Accrued Outsourcing Expenses As part of the process of preparing its financial statements, the Company is required to estimate accrued outsourcing expenses. This process involves identifying services that third parties have performed on the Company’s behalf and estimating the level of service performed and the associated cost incurred for these services as of the balance sheet date. Examples of estimated accrued outsourcing expenses include contract service fees, such as fees payable to contract manufacturers in connection with the production of materials related to the Company’s drug product, and service fees and pass through costs from clinical research organizations. The Company develops estimates of liabilities using its judgment based upon the facts and circumstances known at the time.
Segments	Segments The Company operates in one segment. Management uses one measure of profitability and does not segment its business for internal reporting.
Research and Development	Research and Development Research and development costs are expensed as incurred. These consist primarily of salaries, contract services, and supplies. Costs, if any, related to clinical trial and drug manufacturing activities are based upon estimates of the services received and related expenses incurred by contract research organizations (CROs), clinical study sites, drug manufacturers, collaboration partners, laboratories, consultants, or otherwise. Related contracts vary significantly in length, and could be for a fixed amount, a variable amount based on actual costs incurred, capped at a certain limit, or for a combination of these elements. Activity levels are monitored through communications with the vendors, including detailed invoices and task completion review, analysis of expenses against budgeted amounts, and pre-approval of any changes in scope of the services to be performed. Certain significant vendors may also provide an estimate of costs incurred but not invoiced on a periodic basis. Expenses related to the CROs and clinical studies, as well as contract drug manufacturers, are primarily based on progress made against specified milestones or targets in each period. In accordance with certain research and development agreements, the Company is obligated to make certain upfront payments upon execution of the agreement. The Company records these upfront payments as prepaid research and development expenses, which are included in Other current assets or Other assets in the accompanying Balance Sheets. Such payments are recorded to research and development expense as services are performed. The Company evaluates on a quarterly basis whether events and circumstances have occurred that may indicate impairment of remaining prepaid research and development expenses.
Stock-Based Compensation	Stock-Based Compensation The Company’s stock-based compensation cost recognized is based on the estimated grant date fair value. The Company recognizes compensation costs for its stock-based awards on a straight-line basis over the requisite service period for the entire award, as adjusted for expected forfeitures.
Income Taxes	Income Taxes The current benefit for income taxes represents actual or estimated amounts payable or refundable on tax returns filed or to be filed each year. Deferred tax assets and liabilities are recognized for the estimated future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases and operating loss and tax credit carryforwards. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in the period that includes the enactment date. The overall change in deferred tax assets and liabilities for the period measures the deferred tax expense or benefit for the period. The measurement of deferred tax assets may be reduced by a valuation allowance based on judgmental assessment of available evidence if deemed more likely than not that some or all of the deferred tax assets will not be realized.

BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Accrued expenses and other liabilities (related party - $0 and $216 at December 31, 2023 and 2022, respectively)	$ 175	$ 625
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, issued	0	0
Preferred stock, outstanding	0	0
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	14,501,143	14,410,143
Common stock, shares outstanding	14,501,143	14,410,143
Related Party [Member]
Accrued expenses and other liabilities (related party - $0 and $216 at December 31, 2023 and 2022, respectively)	$ 0	$ 216

STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	12 Months Ended
STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Costs and expenses:
General and administrative	$ 6,283	$ 5,847
Research and development (related party - $(91) and $432 as of the years ended December 31, 2023 and 2022, respectively)	1,013	4,749
Total costs and expenses	7,296	10,596
Loss from operations	(7,296)	(10,596)
Interest and other income	1,957	675
Other loss		(5)
Net loss	$ (5,339)	$ (9,926)
Net loss per share:
Basic	$ (0.37)	$ (0.69)
Diluted	$ (0.37)	$ (0.69)
Weighted average shares outstanding:
Basic	14,415,877	14,410,143
Diluted	14,415,877	14,410,143

Property and Equipment

12 Months Ended

Dec. 31, 2023

Property, Plant and Equipment [Abstract]

Property and Equipment

(4) Property and Equipment

Property and equipment consist of the following (in thousands):


	Estimated Life	December 31, 2023			December 31, 2022
Computer equipment	3 years	$	39		$	39
Lab equipment	5 years		130			130
Furniture and fixtures	5 years		37			44
Computer software	3 years		16			16
			222			229
Accumulated depreciation and amortization			(212	)		(204	)
Property and equipment, net		$	10		$	25

For the years ended December 31, 2023 and 2022, depreciation and amortization expense was $15,000 and $20,000, respectively.

BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 37,431	$ 42,445
Other current assets	161	254
Total current assets	37,592	42,699
Right-of-use asset - operating	247	343
Property and equipment, net	10	25
Other assets	12	18
Total assets	37,861	43,085
Current liabilities:
Accounts payable	362	334
Accrued compensation and employee benefits	100	173
Accrued expenses and other liabilities (related party - $0 and $216 at December 31, 2023 and 2022, respectively)	175	625
Total current liabilities	637	1,132
Operating lease liability, net of current portion	204	280
Total liabilities	841	1,412
Commitments and contingencies
Stockholders’ equity:
Preferred stock, $0.001 par value; 5 million shares authorized; no shares issued or outstanding at December 31, 2023 and 2022
Common stock, $0.001 par value; 100 million shares authorized at December 31, 2023 and 2022; 14,501,143 and 14,410,143 shares issued and outstanding at December 31, 2023 and 2022, respectively	14	14
Additional paid-in capital	225,747	225,061
Accumulated deficit	(188,741)	(183,402)
Total stockholders’ equity	37,020	41,673
Total liabilities and stockholders’ equity	$ 37,861	$ 43,085

Fair Value Disclosures (Details Textual) - USD ($)	12 Months Ended
Fair Value Disclosures (Details Textual) - USD ($)	Dec. 31, 2023	Dec. 31, 2022
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Transfers of assets between fair value hierarchy levels	$ 0	$ 0
Debt outstanding	0	0
Fair Value Measurements, Recurring \| Level 1 \| Money Market Funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents consisting of money market funds and commercial paper	$ 37,400,000	$ 42,400,000

Pay vs Performance Disclosure - USD ($) $ in Thousands	12 Months Ended
Pay vs Performance Disclosure - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Pay vs Performance Disclosure
Net Income (Loss)	$ (5,339)	$ (9,926)

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
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+ Details

Property and Equipment - Summary of Property and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Property Plant And Equipment [Line Items]
Property and Equipment, Gross	$ 222	$ 229
Accumulated depreciation and amortization	(212)	(204)
Property and equipment, net	$ 10	25
Computer Equipment
Property Plant And Equipment [Line Items]
Estimated Life	3 years
Property and Equipment, Gross	$ 39	39
Lab Equipment
Property Plant And Equipment [Line Items]
Estimated Life	5 years
Property and Equipment, Gross	$ 130	130
Furniture and Fixtures
Property Plant And Equipment [Line Items]
Estimated Life	5 years
Property and Equipment, Gross	$ 37	44
Computer Software
Property Plant And Equipment [Line Items]
Estimated Life	3 years
Property and Equipment, Gross	$ 16	$ 16

Property and Equipment (Details Textual) - USD ($)	12 Months Ended
Property and Equipment (Details Textual) - USD ($)	Dec. 31, 2023	Dec. 31, 2022
Property, Plant and Equipment [Abstract]
Depreciation and amortization expense	$ 15,000	$ 20,000

Insider Trading Policies and Procedures	12 Months Ended
Insider Trading Policies and Procedures	Dec. 31, 2023
Insider Trading Policies and Procedures [Line Items]
Insider Trading Policies and Procedures Adopted	true

Commitments and Contingencies - Future Minimum Commitments due Under October 2020 Lease Agreement (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Commitments and Contingencies Disclosure [Abstract]
2024	$ 93
2025	96
2026	100
2027	25
Total remaining lease payments	314
Less: imputed lease interest	(34)
Less: Current portion	$ (76)
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Accrued expenses and other liabilities (related party - $0 and $216 at December 31, 2023 and 2022, respectively)
Operating lease liability, net of current portion	$ 204	$ 280

Commitments and Contingencies (Tables)

12 Months Ended

Dec. 31, 2023

Commitments and Contingencies Disclosure [Abstract]

Future Minimum Commitments due Under October 2020 Lease Agreement

Future minimum commitments due under the October 2020 Lease agreement as of December 31, 2023 are as follows (in thousands):


2024	$	93
2025		96
2026		100
2027		25
Total remaining lease payments		314
Less: imputed lease interest		(34	)
Less: Current portion		(76	)
Operating lease liability, net of current portion	$	204

Income Taxes - Income Tax Benefit Attributable to Our Loss from Operations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Effective Income Tax Rate Reconciliation, Amount [Abstract]
U.S. federal income tax benefit at statutory rates	$ (1,121)	$ (2,085)
State income tax benefit, net of federal benefit	(192)	(357)
Research and experimentation credits	0	0
Deferred tax asset adjustment	47	2
Other	107	186
Change in valuation allowance	1,159	2,254
Income tax benefit	$ 0	$ 0

- Definition

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

+ References + Details

Share-based Compensation - Summary of Non-cash, Share-based Compensation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total expenses	$ 686	$ 556
General and administrative
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total expenses	526	423
Research and development
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total expenses	$ 160	$ 133

Fair Value Disclosures

12 Months Ended

Dec. 31, 2023

Fair Value Disclosures [Abstract]

Fair Value Disclosures

(3) Fair Value Disclosures

Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date (exit price). Inputs used to measure fair value are classified into the following hierarchy:

•

Level 1—Unadjusted quoted prices in active markets for identical assets or liabilities. The Company’s Level 1 assets consist of money market investments. The Company does not have any Level 1 liabilities.

•

Level 2—Unadjusted quoted prices in active markets for similar assets or liabilities; unadjusted quoted prices for identical or similar assets or liabilities in markets that are not active; or inputs other than quoted prices that are observable for the asset or liability. The Company’s Level 2 assets consist of corporate bonds and commercial paper securities. The Company does not have any Level 2 liabilities.

•

Level 3—Unobservable inputs for the asset or liability. The Company does not have any Level 3 assets or liabilities.

As of December 31, 2023 and 2022, the Company had $37.4 million and $42.4 million, respectively, of cash equivalents consisting of money market funds with original maturities of 90 days or less. The Company has the ability to liquidate these investments without restriction. The Company determines fair value for these money market funds with Level 1 inputs through quoted market prices. There were no transfers between any fair value hierarchy levels in 2023 or 2022.

Fair Value of Other Financial Instruments

The carrying amount of other financial instruments, including accounts payable, approximated fair value due to their short maturities. As of December 31, 2023 and 2022, the Company did not have any debt outstanding.

- 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

Income Taxes - Net deferred tax assets and liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Deferred tax assets:
Net operating loss carryforwards	$ 51,190	$ 50,008
Charitable contribution carryforwards	371	393
Research and experimentation credits	2,420	2,420
Capitalized research and development costs	951	979
Capitalized intangibles	354	356
Stock-based compensation	232	205
Accrued compensation	7	6
Lease liabilities	69	94
Total deferred tax assets	55,594	54,461
Valuation allowance	(55,531)	(54,372)
Deferred tax assets, net of valuation allowance	63	89
Deferred tax liabilities:
Right-of-use asset	(61)	(84)
Depreciation and amortization	(2)	(5)
Net deferred tax liability	$ 0	$ 0

Insider Trading Arrangements	3 Months Ended
Insider Trading Arrangements	Dec. 31, 2023
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false
Rule 10b5 1 Arr Modified [Flag]	false
Non-Rule 10b5-1 ArrModified [Flag]	false

Employee Benefit Plans (Details Textual) - USD ($)	12 Months Ended
Employee Benefit Plans (Details Textual) - USD ($)	Dec. 31, 2023	Dec. 31, 2022
Defined Contribution Plan Disclosure [Line Items]
Matching contribution	matching contribution equal to 100% of the employee’s first 3% of the employee’s contributions and 50% of the employee’s next 2% of contributions.
Company's contribution	$ 56,000	$ 96,000
First 3% of pay contributed
Defined Contribution Plan Disclosure [Line Items]
Benefit Plan, Percentage of Match	100.00%
Employer matching contribution percentage	3.00%
Next 2% of pay contributed
Defined Contribution Plan Disclosure [Line Items]
Benefit Plan, Percentage of Match	50.00%
Employer matching contribution percentage	2.00%

Employee Benefit Plans

12 Months Ended

Dec. 31, 2023

Retirement Benefits [Abstract]

Employee Benefit Plans

(9) Employee Benefit Plans

The Company has a 401(k) plan and makes a matching contribution equal to 100% of the employee’s first 3% of the employee’s contributions and 50% of the employee’s next 2% of contributions. The Company adopted the plan in 2006 and contributed $56,000 and $96,000 for the years ended December 31, 2023 and 2022, respectively.

- Definition

The entire disclosure for retirement benefits.

+ References

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+ Details

Share-based Compensation

12 Months Ended

Dec. 31, 2023

Share-Based Payment Arrangement [Abstract]

Share-based Compensation

(8) Share-based Compensation

Stock Plans

The Company’s equity incentive plan, the 2020 Equity Incentive Plan (the Equity Plan), was approved by stockholders on December 10, 2020. The maximum number of shares issuable under this plan is 1,167,425 shares.

The Equity Plan provides for the granting of stock options (including indexed options), restricted stock units, stock appreciation rights, restricted stock purchase rights, restricted stock bonuses, performance shares, performance units and deferred stock units. Under the Equity Plan, awards may be granted to employees, directors and consultants of ARCA, except for incentive stock options, which may be granted only to employees. As of December 31, 2023, options to purchase 601,900 shares with a weighted average exercise price of $3.45 per share were outstanding under the Equity Plan, and 459,718 shares were reserved for future awards.

In general, the Equity Plan authorizes the grant of stock options that vest at rates set by the Board of Directors or the Compensation Committee thereof. Generally, stock options granted by ARCA under the equity incentive plans become exercisable ratably for a period of three to four years from the date of grant and have a maximum term of ten years. The exercise prices of stock options under the equity incentive plan generally meet the following criteria: the exercise price of incentive stock options must be at least 100% of the fair market value on the grant date and exercise price of options granted to 10% (or greater) stockholders must be at least 110% of the fair market value on the grant date.

In conjunction with the adoption of the Equity Plan, the Company discontinued grants under the 2013 Plan, effective December 10, 2020. As of December 31, 2023, options to purchase 14,807 shares with a weighted average exercise price of $57.73 per share were outstanding under the 2013 plan.

The Company did not grant options in 2023. The Company granted options to purchase an aggregate of 60,000 shares of common stock in the year ended December 31, 2022. The fair values of employee stock options granted in the year ended December 31, 2022 were estimated at the date of grant using the Black-Scholes model with the following assumptions and had the following estimated weighted average grant date fair value per share:


	Year Ended December 31,
	2022
Expected term	5.5 years
Expected volatility		107	%
Risk-free interest rate		3.56	%
Expected dividend yield		0	%
Weighted-average grant date fair value per share	$	1.87

A summary of ARCA’s stock option activities for the years ended December 31, 2023 and 2022, and related information as of December 31, 2023, is as follows:


	Options Outstanding
	Number of Options			Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (in years)		Aggregate Intrinsic Value (in thousands)
Options outstanding - December 31, 2021		904,123		$	5.59
Granted		60,000			2.31
Exercised		—			—
Forfeited and cancelled		(259,163	)		4.74
Options outstanding - December 31, 2022		704,960		$	5.62		8.29	$	18
Granted		—			—
Exercised		—			—
Forfeited and cancelled		(88,253	)		11.68
Options outstanding - December 31, 2023		616,707		$	4.76		7.35	$	—
Options exercisable - December 31, 2023		463,068		$	5.28		7.29	$	—
Options vested and expected to vest - December 31, 2023		616,661		$	4.76		7.35	$	—

The aggregate intrinsic value in the table above represents the total intrinsic value, based on our closing price as of December 31 of the respective year, which would have been received by the option holders had all the option holders with in-the-money options exercised as of that date. As of December 31, 2023, the unrecognized compensation expense related to unvested options, excluding estimated forfeitures, was $367,000 which is expected to be recognized over a weighted average period of 1.1 years. The Company recognizes compensation costs for its share-based awards on a straight-line basis over the requisite service period for the entire award, as adjusted for expected forfeitures.

Restricted Stock Units

The Company granted restricted stock units (RSUs) under the Equity Plan to employees during 2022. The fair value of RSU awards is the closing price of the Company's common stock on the date of the grant and is recognized as compensation expense on a straight-line basis over the respective vesting period. The stock awards granted had a requisite service period of one year.

A summary of RSU activity for the year ended December 31, 2023 is presented below:


	Restricted Stock Units Outstanding
	Number of Shares			Weighted Average Grant Date Fair Value
RSUs outstanding - December 31, 2021		—		$	—
Granted		91,000			2.21
Vested and released		—			—
Forfeited and cancelled		—			—
RSUs outstanding - December 31, 2022		91,000		$	2.21
Granted		—			—
Vested and released		(91,000	)		2.21
Forfeited and cancelled		—			—
RSUs outstanding - December 31, 2023		—		$	—

As of December 31, 2023, there was no unrecognized compensation cost related to unvested stock awards.

Non-cash Stock-based Compensation

For the years ended December 31, 2023 and 2022, the Company recognized the following non-cash, share-based compensation expense (in thousands):


	Years Ended
	December 31,
	2023		2022
General and administrative	$	526	$	423
Research and development		160		133
Total	$	686	$	556

ARCA did not recognize any tax benefit related to employee stock-based compensation cost as a result of the full valuation allowance on its net deferred tax assets.

Net Loss Per Share - Summary of Potentially Dilutive Shares of Common Stock (Details) - shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	616,707	795,960
Outstanding stock options
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	616,707	704,960
Unvested restricted stock units
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount		91,000

Commitments and Contingencies (Details Textual) € in Millions			1 Months Ended		12 Months Ended
	Nov. 30, 2023	Aug. 29, 2020 ft²	Jul. 31, 2021 EUR (€)	Jun. 30, 2021 ft²	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($) Employee
Commitments And Contingencies [Line Items]
Amount of retention bonuses					$ 311,000
Workforce reduction, percentage						67.00%
Workforce reduction, number of employees \| Employee						12
Percentage of retention bonuses	50.00%
Retention bonus paid					86,000
Severance expense					159,000
Restructuring Reserve, Current					$ 0
Area of office facilities taken on lease \| ft²		5,200
Operating lease term		42 months
Additional operating lease term		36 months
Lease renewal option		option to renew for an additional 36 month term at the then prevailing rental rate.
Lessee, Operating Lease, Existence of Option to Extend [true false]		true
Area of additional office facilities taken on sublease \| ft²				3,000
Operating sublease term				29 months
Lessee, operating lease, assumptions and judgments, allocation of lease and nonlease component					The leases include real estate taxes and insurance, which is not a lease component and is not included in the lease obligation. In addition, common area maintenance charges are based on actual costs incurred and are a non-lease component that is not included in the lease obligation.
Operating lease, cash paid for measurement of lease liabilities					$ 127,000	$ 131,000
Lease liability					$ 280,000
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]					Accrued expenses and other liabilities (related party - $0 and $216 at December 31, 2023 and 2022, respectively)
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]					Operating lease liability, net of current portion
Weighted-average remaining lease term					3 years 2 months 12 days
Weighted-average discount rate					7.00%
Clinical development decisions
Commitments And Contingencies [Line Items]
Amount of retention bonuses						265,000
Research and development \| Patent Assignment Agreement \| University Medical Center of Johannes Gutenberg University Mainz
Commitments And Contingencies [Line Items]
Potential upfront and milestone obligations and royalty obligations \| €			€ 1.6
General and Administrative Expense
Commitments And Contingencies [Line Items]
Rent expense					$ 119,000	125,000
One-time Termination Benefits
Commitments And Contingencies [Line Items]
Restructuring charges						755,000
One-time Termination Benefits \| Research and development
Commitments And Contingencies [Line Items]
Restructuring charges						470,000
One-time Termination Benefits \| General and Administrative Expense
Commitments And Contingencies [Line Items]
Restructuring charges						$ 285,000

Equity Financings (Details Textual) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Jul. 22, 2020
Equity Financing [Line Items]
Common stock, par value	$ 0.001	$ 0.001
JonesTrading
Equity Financing [Line Items]
Percentage of selling commission per additional shares sold			3.00%
Sales Agreement \| JonesTrading
Equity Financing [Line Items]
Common stock, par value			$ 0.001
Aggregate offering price of common stock authorized			$ 54.0
2020 Sales Agreement
Equity Financing [Line Items]
Sale of common stock	0	0

Share-based Compensation - Estimated Weighted Average Grant Date Fair Value Per Share (Details)	12 Months Ended
	Dec. 31, 2022 $ / shares
Estimated weighted average grant date fair value per share
Expected term	5 years 6 months
Expected volatility	107.00%
Risk-free interest rate	3.56%
Expected dividend yield	0.00%
Weighted-average grant date fair value per share	$ 1.87

Net Loss Per Share (Tables)

12 Months Ended

Dec. 31, 2023

Earnings Per Share [Abstract]

Summary of Potentially Dilutive Shares of Common Stock

Because the Company reported a net loss for the years ended December 31, 2023 and 2022, all potentially dilutive shares of common stock have been excluded from the computation of the dilutive net loss per share for all periods presented. Such potentially dilutive shares of common stock consist of the following:


	Years Ended December 31,
	2023		2022
Potentially dilutive securities, excluded:
Outstanding stock options		616,707		704,960
Unvested restricted stock units		—		91,000
		616,707		795,960

STATEMENTS OF OPERATIONS (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Related Party [Member]
Related party expense	$ (91)	$ 432

Related Party Arrangements (Details Textual) - Chief Executive Officer - USD ($)	1 Months Ended	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2023	Dec. 31, 2022
Related Party Transaction [Line Items]
Related party expense		$ (91,000)	$ 432,000
Payment of unrestricted research grants	$ 125,000

Document and Entity Information - USD ($)

12 Months Ended

Dec. 31, 2023

Jan. 31, 2024

Jun. 30, 2023

Cover [Abstract]

Entity Registrant Name

ARCA BIOPHARMA, INC.

Entity Central Index Key

0000907654

Document Type

10-K

Amendment Flag

false

Document Period End Date

Dec. 31, 2023

Document Fiscal Period Focus

Trading Symbol

ABIO

Document Fiscal Year Focus

2023

Current Fiscal Year End Date

--12-31

Entity Well-known Seasoned Issuer

Entity Voluntary Filers

Entity Current Reporting Status

Yes

Entity Filer Category

Non-accelerated Filer

Entity Small Business

true

Entity Emerging Growth Company

false

Entity Shell Company

false

Entity Public Float

$ 20,914,221

Entity Common Stock, Shares Outstanding

14,501,143

Entity Interactive Data Current

Yes

Entity File Number

000-22873

Entity Tax Identification Number

36-3855489

Entity Address, Address Line One

10170 Church Ranch Way

Entity Address, Address Line Two

Suite 100

Entity Address, City or Town

Westminster

Entity Address, State or Province

Entity Address, Postal Zip Code

80021

City Area Code

720

Local Phone Number

940-2200

Document Annual Report

true

Document Transition Report

false

Title of 12(b) Security

Common Stock, par value $0.001 per share

Security Exchange Name

NASDAQ

Entity Incorporation, State or Country Code

Auditor Firm ID

185

Auditor Name

KPMG LLP

Auditor Location

Denver, CO

Documents Incorporated by Reference

DOCUMENTS INCORPORATED BY REFERENCE


Auditor Firm Id:	185	Auditor Name:	KPMG LLP	Auditor Location:	Denver, CO

Document Financial Statement Error Correction [Flag]

false

Share-based Compensation (Details Textual) - USD ($)	12 Months Ended
Share-based Compensation (Details Textual) - USD ($)	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 10, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares outstanding under Equity plan	616,707	704,960	904,123
Weighted Average exercise Price of Options Outstanding	$ 4.76	$ 5.62	$ 5.59
Stock options award, expiration	10 years
Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized compensation expense related to unvested options	$ 367,000
Maturity period of weighted average period of compensation expenses	1 year 1 month 6 days
Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Requisite service period of stock awards granted	1 year
Unrecognized compensation expense related to unvested stock awards	$ 0
Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock options award, vesting period	3 years
Percentage holding for stock options exercise price	10.00%
Minimum \| Incentive Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of exercise price of stock option	100.00%
Minimum \| Incentive Stock Option \| Stockholders
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of exercise price of stock option	110.00%
Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock options award, vesting period	4 years
2020 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares issuable under Equity plan				1,167,425
Number of shares outstanding under Equity plan	601,900
Weighted Average exercise Price of Options Outstanding	$ 3.45
Shares reserved for future	459,718
Options granted	0	60,000
2013 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares outstanding under Equity plan	14,807
Weighted Average exercise Price of Options Outstanding	$ 57.73

STATEMENTS OF CASH FLOWS - USD ($)	12 Months Ended
STATEMENTS OF CASH FLOWS - USD ($)	Dec. 31, 2023	Dec. 31, 2022
Cash flows from operating activities:
Net Income (Loss)	$ (5,339,000)	$ (9,926,000)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation	15,000	20,000
Amortization of right-of-use asset - operating	96,000	94,000
Share-based compensation	686,000	556,000
Loss from disposal of property and equipment		5,000
Change in operating assets and liabilities:
Other current assets	93,000	808,000
Other assets	6,000	0
Accounts payable	28,000	(783,000)
Accrued compensation and employee benefits	(73,000)	(752,000)
Accrued expenses and other liabilities	(526,000)	(934,000)
Net cash used in operating activities	(5,014,000)	(10,912,000)
Cash flows from investing activities:
Purchase of property and equipment	0	(2,000)
Net cash used in investing activities	0	(2,000)
Cash flows from financing activities:
Net cash provided by financing activities	0	0
Net increase in cash and cash equivalents	(5,014,000)	(10,914,000)
Cash and cash equivalents, beginning of year	42,445,000	53,359,000
Cash and cash equivalents, end of year	$ 37,431,000	$ 42,445,000

Property and Equipment (Tables)

12 Months Ended

Dec. 31, 2023

Property, Plant and Equipment [Abstract]

Summary of Property and Equipment

Property and equipment consist of the following (in thousands):


	Estimated Life	December 31, 2023			December 31, 2022
Computer equipment	3 years	$	39		$	39
Lab equipment	5 years		130			130
Furniture and fixtures	5 years		37			44
Computer software	3 years		16			16
			222			229
Accumulated depreciation and amortization			(212	)		(204	)
Property and equipment, net		$	10		$	25

STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Accumulated Deficit
Beginning Balance at Dec. 31, 2021	$ 51,043	$ 14	$ 224,505	$ (173,476)
Beginning Balance, shares at Dec. 31, 2021		14,410,143
Share-based compensation	556		556
Net Income (Loss)	(9,926)			(9,926)
Ending Balance at Dec. 31, 2022	$ 41,673	$ 14	225,061	(183,402)
Ending Balance, shares at Dec. 31, 2022	14,410,143	14,410,143
Issuance of common stock upon vesting of Restricted Stock Units		91,000
Share-based compensation	$ 686		686
Net Income (Loss)	(5,339)			(5,339)
Ending Balance at Dec. 31, 2023	$ 37,020	$ 14	$ 225,747	$ (188,741)
Ending Balance, shares at Dec. 31, 2023	14,501,143	14,501,143

- Definition

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

+ References

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- Definition

Amount of equity (deficit) attributable to parent. Excludes temporary equity and equity attributable to noncontrolling interest.

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+ Details

Share-based Compensation - Summary of RSU Activity (Details) - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Number of Shares, RSUs outstanding, beginning of period	91,000
Number of Shares, RSUs outstanding, Granted		91,000
Number of Shares, RSUs outstanding, Vested and released	(91,000)
Number of Shares, RSUs outstanding, end of period		91,000
RSUs, Weighted Average Grant Date Fair Value
Weighted Average Grant Date Date Fair Value, RSUs outstanding, beginning of period	$ 2.21
Weighted Average Grant Date Date Fair Value, RSUs outstanding, Granted		$ 2.21
Weighted Average Grant Date Date Fair Value, RSUs outstanding, Vested and released	$ 2.21
Weighted Average Grant Date Date Fair Value, RSUs outstanding, end of period		$ 2.21

Commitments and Contingencies

12 Months Ended

Dec. 31, 2023

Commitments and Contingencies Disclosure [Abstract]

Commitments and Contingencies

(6) Commitments and Contingencies

The Company has or is subject to the following commitments and contingencies:

Employment Agreements and Reduction of Workforce

The Company maintains employment agreements with several key executive employees. The agreements may be terminated at any time by the Company with or without cause upon written notice to the employee, and entitle the employee to wages in lieu of notice for periods not exceeding one calendar year from date of termination without cause or by the employee for good reason. Certain of these agreements also provide for payments to be made under certain conditions related to a change in control of the Company.

In December 2022, the Company's Board of Directors approved retention bonuses for certain employees, subject to continued employment with the Company through the earlier of a change in control of the Company or certain clinical development decisions totaling $265,000. In November 2023, the retention bonuses were amended to increase the aggregate amount of the retention bonus by 50% and in order to assist with tax obligations associated with the vesting of certain Company restricted stock unit awards in December 2023, a total of $86,000 was paid in December 2023. As of December 31, 2023, the unpaid retention bonuses totaled $311,000, none of which was accrued as of December 31, 2023, since there had not been a change in control or clinical development decision.

The Company and Christopher D. Ozeroff, the Secretary, Senior Vice President and General Counsel of ARCA mutually agreed to conclude Mr. Ozeroff’s employment effective March 31, 2023. Pursuant to Mr. Ozeroff's existing employment agreement, as previously amended, ARCA will provide Mr. Ozeroff severance benefits pursuant to the terms of his existing employment agreement with the Company, as previously amended. The severance benefits include severance payments and reimbursement to cover out-of-pocket costs to continue group health insurance benefits under COBRA, whether he elects or is eligible to receive COBRA (provided, that even if he does not elect or is not eligible to receive COBRA, he will receive the equivalent of such out-of-pocket expenses paid by him not to exceed the costs that the benefits would equal under COBRA if he were so eligible). During the year ended December 31, 2023, the Company recorded an expense of $159,000 for these severance benefits, none of which remains unpaid.

In 2022, the Company implemented a strategic reduction of the workforce by approximately 67%, or 12 employees. Personnel reductions were primarily focused in research and development and general and administrative functions. The restructuring was a result of the Company’s decision to manage operating costs and expenses. During the year ended December 31, 2022, the Company recorded total restructuring charges of approximately $755,000, of which $470,000 and $285,000 were recognized in research and

development and general and administrative expenses, respectively, in connection with the restructuring, all in the form of one-time termination benefits, none of which remains unpaid.

Operating Lease

On August 29, 2020 the Company entered into a lease agreement for approximately 5,200 square feet of office facilities in Westminster, Colorado which serves as the Company’s primary business office effective October 1, 2020 (October 2020 Lease). The lease term is 42 months beginning October 1, 2020 and includes an option to renew for an additional 36 month term at the then prevailing rental rate. The exercise of the lease renewal option is at the Company’s sole discretion. The amounts recorded assume the Company will exercise its renewal option. In June 2021, the Company entered into a sublease agreement for approximately 3,000 square feet of additional office facilities in the Company’s primary business office (2021 Lease). The sublease term was 29 months and terminated in October 2023. The leases include real estate taxes and insurance, which is not a lease component and is not included in the lease obligation. In addition, common area maintenance charges are based on actual costs incurred and are a non-lease component that is not included in the lease obligation.

Future minimum commitments due under the October 2020 Lease agreement as of December 31, 2023 are as follows (in thousands):


2024	$	93
2025		96
2026		100
2027		25
Total remaining lease payments		314
Less: imputed lease interest		(34	)
Less: Current portion		(76	)
Operating lease liability, net of current portion	$	204

Rent expense, which is included in general and administrative expense, under these leases for the years ended December 31, 2023 and 2022 was $119,000 and $125,000, respectively.

As of December 31, 2023, the lease liability was $280,000 and the current portion is included in accrued expenses and other liabilities and the non-current portion is in operating lease liability, net of current portion in the accompanying balance sheet. Cash paid for amounts included in the measurement of lease liabilities and the operating cash flows from operating leases for the years ended December 31, 2023 and 2022 were $127,000 and $131,000, respectively. The weighted-average remaining lease term for the operating lease as of December 31, 2023 is 3.2 years. The weighted-average discount rate for the operating lease is 7%.

Patent Agreement

In July 2021, the Company entered into a patent assignment agreement (the Agreement) with the University Medical Center of Johannes Gutenberg University Mainz, Germany.

Under the terms of the Agreement, the Company received exclusive world-wide patent rights relating to the use of rNAPc2 as a potential treatment for COVID-19, and other indications, based on the research and discoveries from Univ.-Prof. Dr. Wolfram Ruf, the Scientific Director and Alexander von Humboldt Professor at the Center for Thrombosis and Hemostasis (CTH) of the University Medical Center Mainz, and his collaborators. The Company has upfront and potential milestone obligations to the University Medical Center Mainz that could total approximately €1.6 million and royalty obligations in the low single digit range, if rNAPc2 receives regulatory approval and is commercialized. The term of the Agreement extends to the date of expiration of the last to expire of any of the assigned patents.

Gencaro License

ARCA has licensed worldwide rights to all preclinical and clinical data through the BEST trial for development of bucindolol. The patents that were the subject of this license are expired. If the license agreement is deemed enforceable, the Company would incur milestone and royalty obligations upon the occurrence of certain events, including if the FDA grants marketing approval for Gencaro, upon regulatory marketing approval in Europe and Japan and based on achievement of specified product sales levels.

The Company and Summary of Significant Accounting Policies (Details Textual)	12 Months Ended
	Dec. 31, 2023 USD ($) Segment
Accounting Policies [Abstract]
Revenues	$ 0
Concentrations of credit risk	$ 0
Number of segments \| Segment	1

- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

+ Details

Share-based Compensation - Summary of Stock Option Activities (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Number of Stock Options
Number of Options, Options outstanding, beginning of period	704,960	904,123
Number of Options, Granted		60,000
Number of Options, Forfeited and cancelled	(88,253)	(259,163)
Number of Options, Options outstanding, end of period	616,707	704,960
Number of Options, Options exercisable, end of period	463,068
Number of Options, Options vested and expected to vest	616,661
Stock Options, Weighted Average Exercise Price
Weighted Average Exercise Price, Options outstanding, beginning of period	$ 5.62	$ 5.59
Weighted Average Exercise Price, Granted		2.31
Weighted Average Exercise Price, Forfeited and cancelled	11.68	4.74
Weighted Average Exercise Price, Options outstanding, end of period	4.76	$ 5.62
Weighted Average Exercise Price, Options exercisable, end of period	5.28
Weighted Average Exercise Price, Options vested and expected to vest, end of period	$ 4.76
Stock Options, Weighted Average Remaining Contractual Term
Weighted Average Remaining Contractual Term (in years), Options outstanding	7 years 4 months 6 days	8 years 3 months 14 days
Weighted Average Remaining Contractual Term (in years), Options exercisable	7 years 3 months 14 days
Weighted Average Remaining Contractual Term (in years), Options vested and expected to vest	7 years 4 months 6 days
Share Options, Aggregate Intrinsic Value
Aggregate intrinsic value, Options Outstanding, end of period		$ 18

Share-based Compensation (Tables)

12 Months Ended

Dec. 31, 2023

Share-Based Payment Arrangement [Abstract]

Estimated Weighted Average Grant Date Fair Value per Share

The Company granted options to purchase an aggregate of 60,000 shares of common stock in the year ended December 31, 2022. The fair values of employee stock options granted in the year ended December 31, 2022 were estimated at the date of grant using the Black-Scholes model with the following assumptions and had the following estimated weighted average grant date fair value per share:


	Year Ended December 31,
	2022
Expected term	5.5 years
Expected volatility		107	%
Risk-free interest rate		3.56	%
Expected dividend yield		0	%
Weighted-average grant date fair value per share	$	1.87

Summary of Stock Option Activities

A summary of ARCA’s stock option activities for the years ended December 31, 2023 and 2022, and related information as of December 31, 2023, is as follows:


	Options Outstanding
	Number of Options			Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (in years)		Aggregate Intrinsic Value (in thousands)
Options outstanding - December 31, 2021		904,123		$	5.59
Granted		60,000			2.31
Exercised		—			—
Forfeited and cancelled		(259,163	)		4.74
Options outstanding - December 31, 2022		704,960		$	5.62		8.29	$	18
Granted		—			—
Exercised		—			—
Forfeited and cancelled		(88,253	)		11.68
Options outstanding - December 31, 2023		616,707		$	4.76		7.35	$	—
Options exercisable - December 31, 2023		463,068		$	5.28		7.29	$	—
Options vested and expected to vest - December 31, 2023		616,661		$	4.76		7.35	$	—

Summary of RSU Activity

A summary of RSU activity for the year ended December 31, 2023 is presented below:


	Restricted Stock Units Outstanding
	Number of Shares			Weighted Average Grant Date Fair Value
RSUs outstanding - December 31, 2021		—		$	—
Granted		91,000			2.21
Vested and released		—			—
Forfeited and cancelled		—			—
RSUs outstanding - December 31, 2022		91,000		$	2.21
Granted		—			—
Vested and released		(91,000	)		2.21
Forfeited and cancelled		—			—
RSUs outstanding - December 31, 2023		—		$	—

Summary of Non-cash, Share-based Compensation Expense

For the years ended December 31, 2023 and 2022, the Company recognized the following non-cash, share-based compensation expense (in thousands):


	Years Ended
	December 31,
	2023		2022
General and administrative	$	526	$	423
Research and development		160		133
Total	$	686	$	556

Income Taxes

12 Months Ended

Dec. 31, 2023

Income Tax Disclosure [Abstract]

Income Taxes

(10) Income Taxes

Effective June 1, 2005, the Company changed from an S-Corporation to a C-Corporation. As an S-Corporation, the net operating loss carryforwards were distributed to the Company’s stockholders; such amounts were not significant. As of December 31, 2023, the Company has net operating loss carryforwards of approximately $208.1 million, and approximately $2.4 million of research and development credits that may be used to offset future taxable income. The Company’s net operating loss carryforwards through December 31, 2017 will expire beginning 2025 through 2037. The net operating loss carryforwards beginning in 2018, have no expiration. Utilization of net operating losses and tax credits, including those acquired as a result of the Merger, will be subject to an annual limitation due to ownership change limitations provided by Internal Revenue Code Section 382. The Company believes that an ownership change limitation as defined under Section 382 of the U.S. Internal Revenue Code occurred as a result of its various historical financing transactions. Future utilization of the federal net operating losses and tax credit carryforwards accumulated from June 2005 to the change in ownership date will be subject to annual limitations to offset future taxable income. The annual limitation

may result in the expiration of the net operating losses and credits before utilization. As such, a portion of the Company’s net operating loss carryforwards may be limited.

In assessing the realizability of deferred tax assets, management considers whether it is more likely than not that some portion or all of the deferred tax assets will not be realized. The ultimate realization of deferred tax assets is dependent upon the generation of future taxable income during the period in which those temporary differences become deductible. Management considers the scheduled reversal of deferred tax liabilities, projected future taxable income and tax planning strategies in making this assessment. Due primarily to the Company’s history of operating losses, management is unable to conclude that it is more likely than not that the Company will realize the benefits of these deductible differences, and accordingly has provided a valuation allowance against the entire net deferred tax assets and liabilities of approximately $55.5 million at December 31, 2023, reflecting an increase of approximately $1.2 million from December 31, 2022. The deferred tax assets are primarily comprised of net operating loss carryforwards and research and experimentation credit carryforwards. As of December 31, 2023, the Company has not performed an Internal Revenue Code Section 382 limitation study. Depending on the outcome of such a study, the gross amount of net operating losses recognizable in future tax periods could be limited. A limitation in the carryforwards would decrease the carrying amount of the gross amount of the net operating loss carryforwards, with a corresponding decrease in the valuation allowance recorded against these gross deferred tax assets.

Income tax benefit attributable to the Company’s loss from operations before income taxes differs from the amounts computed by applying the U.S. federal statutory income tax rate of 21% for 2023 and 2022, as a result of the following (in thousands):


	Years ended December 31,
	2023			2022
U.S. federal income tax benefit at statutory rates	$	(1,121	)	$	(2,085	)
State income tax benefit, net of federal benefit		(192	)		(357	)
Research and experimentation credits		—			—
Deferred tax asset adjustment		47			2
Other		107			186
Change in valuation allowance		1,159			2,254
Income tax benefit	$	—		$	—

Deferred income taxes reflect the net tax effects of temporary differences between the carrying amounts of assets and liabilities for financial reporting and the amounts used for income tax purposes, as well as operating loss and tax credit carryforwards. The income tax effects of temporary differences and carryforwards that give rise to significant portions of the Company’s net deferred tax assets and liabilities consisted of the following (in thousands):


	As of December 31,
	2023			2022
Deferred tax assets:
Net operating loss carryforwards	$	51,190		$	50,008
Charitable contribution carryforwards		371			393
Research and experimentation credits		2,420			2,420
Capitalized research and development costs		951			979
Capitalized intangibles		354			356
Stock-based compensation		232			205
Accrued compensation		7			6
Lease liabilities		69			94
Total deferred tax assets		55,594			54,461
Valuation allowance		(55,531	)		(54,372	)
Deferred tax assets, net of valuation allowance		63			89
Deferred tax liabilities:
Right-of-use asset		(61	)		(84	)
Depreciation and amortization		(2	)		(5	)
Net deferred tax liability	$	—		$	—

Since the Company is in a loss carryforward position, the Company is generally subject to U.S. federal and state income tax examinations by tax authorities for all years for which a loss carryforward is available. Thus, the Company’s open tax years extend back to 2009. The Company believes that its tax filing positions and deductions related to tax periods subject to examination will be

sustained upon audit and does not anticipate any adjustment will result in a material adverse effect on the Company’s financial condition, result of operations, or cash flow. For the years ended December 31, 2023 and 2022, the Company has no reserve for uncertain tax positions. The Company does not expect that the total amounts of unrecognized tax benefits will significantly increase or decrease within the subsequent twelve months. In the event the Company concludes it is subject to interest or penalties arising from uncertain tax positions, the Company will record interest and penalties as a component of other income and expense. No interest or penalties were recognized in the financial statements for the years ended December 31, 2023 and 2022.

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480990/946-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(h)(2))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//740/tableOfContent

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
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-Paragraph 14
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-14

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 21
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-21

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
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-Name Accounting Standards Codification
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-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482526/740-270-50-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 17
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-17

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
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-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 6.I.5.Q1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479360/740-10-S99-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 11.C)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479360/740-10-S99-2

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482603/740-30-50-2

+ Details

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2023

Income Tax Disclosure [Abstract]

Income Tax Benefit Attributable to Our Loss from Operations


	Years ended December 31,
	2023			2022
U.S. federal income tax benefit at statutory rates	$	(1,121	)	$	(2,085	)
State income tax benefit, net of federal benefit		(192	)		(357	)
Research and experimentation credits		—			—
Deferred tax asset adjustment		47			2
Other		107			186
Change in valuation allowance		1,159			2,254
Income tax benefit	$	—		$	—

Net Deferred Tax Assets and Liabilities


	As of December 31,
	2023			2022
Deferred tax assets:
Net operating loss carryforwards	$	51,190		$	50,008
Charitable contribution carryforwards		371			393
Research and experimentation credits		2,420			2,420
Capitalized research and development costs		951			979
Capitalized intangibles		354			356
Stock-based compensation		232			205
Accrued compensation		7			6
Lease liabilities		69			94
Total deferred tax assets		55,594			54,461
Valuation allowance		(55,531	)		(54,372	)
Deferred tax assets, net of valuation allowance		63			89
Deferred tax liabilities:
Right-of-use asset		(61	)		(84	)
Depreciation and amortization		(2	)		(5	)
Net deferred tax liability	$	—		$	—

The Company and Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2023

Accounting Policies [Abstract]

The Company and Summary of Significant Accounting Policies

(1) The Company and Summary of Significant Accounting Policies

Description of Business

ARCA biopharma, Inc. (the Company or ARCA), a Delaware corporation, is headquartered in Westminster, Colorado. The Company is a clinical-stage biopharmaceutical company applying a precision medicine approach to the development and commercialization of genetically targeted therapies for cardiovascular diseases. The Company’s lead product candidate is Gencaro™ (bucindolol hydrochloride) for the treatment of atrial fibrillation (AF) in patients with chronic heart failure (HF).

In April 2022, the Board of Directors established a Special Committee and, in May 2022, retained Ladenburg Thalmann & Co. Inc. to evaluate strategic options, including transactions involving a merger, sale of all or part of the Company’s assets, or other alternatives with the goal of maximizing stockholder value. The Company does not have a defined timeline for the strategic review process and the review may not result in any specific action or transaction.

Liquidity and Going Concern

The Company devotes substantially all of its efforts towards obtaining regulatory approval and raising capital necessary to fund its operations and it is subject to a number of risks associated with clinical research and development, including dependence on key individuals, the development of and regulatory approval of commercially viable products, the need to raise adequate additional financing necessary to fund the development and commercialization of its products, and competition from larger companies. The Company has not generated revenue to date and has incurred substantial losses and negative cash flows from operations since its inception. The Company has historically funded its operations through issuances of common and preferred stock.

The Company believes that its current cash and cash equivalents as of December 31, 2023 will be sufficient to fund its operations through the middle of fiscal year 2025. The Company's review of its strategic options may impact this projection. Changing circumstances may cause us to consume capital significantly faster or slower than currently anticipated. The Company has based these estimates on assumptions that may prove to be wrong, and the Company could exhaust its available financial resources sooner than the Company currently anticipates. Therefore, the Company will have to raise additional capital for clinical trials of Gencaro. The Company may not be able to raise sufficient capital on acceptable terms, or at all, to continue development of Gencaro or rNAPc2 or to otherwise continue operations and may not be able to execute any strategic transaction.

The Company’s liquidity, and its ability to raise additional capital or complete any strategic transaction, depends on a number of factors, including, but not limited to, the following:

•

the costs and timing for the potential additional clinical trials in order to gain possible regulatory approval for Gencaro, rNAPc2, or any other product candidate;

•

the market price of the Company’s stock and the availability and cost of additional equity capital from existing and potential new investors;

•

the Company’s ability to retain the listing of its common stock on the Nasdaq Capital Market;

•

general economic and industry conditions affecting the availability and cost of capital, including as a result of deteriorating market conditions due to investor concerns regarding inflation, adverse developments affecting the financial services industry, continued hostilities between Russia and Ukraine and Hamas’ attack against Israel and the ensuing conflict;

•

the Company’s ability to control costs associated with its operations;

•

the costs of filing, prosecuting, defending and enforcing any patent claims and other intellectual property rights; and

•

the terms and conditions of the Company’s existing collaborative and licensing agreements.

The sale of additional equity or convertible debt securities would likely result in substantial additional dilution to the Company’s stockholders. If the Company raises additional funds through the incurrence of indebtedness, the obligations related to such indebtedness would be senior to rights of holders of the Company’s capital stock and could contain covenants that would restrict the Company’s operations. The Company also cannot predict what consideration might be available, if any, to the Company or its stockholders, in connection with any strategic transaction. Should strategic alternatives or additional capital not be available to the Company, or not be available on acceptable terms, the Company may be unable to realize value from its assets and discharge its liabilities in the normal course of business which may, among other alternatives, cause the Company to further delay, substantially reduce or discontinue operational activities to conserve its cash resources.

Basis of Presentation

The accompanying financial statements have been prepared in accordance with U.S. generally accepted accounting principles (U.S. GAAP) and include all adjustments necessary for the fair presentation of our financial position, results of operations and cash flows for the periods presented. Management has performed an evaluation of the Company’s activities through the date of filing of this Annual Report on Form 10-K.

Recent Accounting Pronouncements

The Company reviewed all other recently issued accounting pronouncements and concluded that they were either not applicable or not expected to have a significant impact to the financial statements.

Accounting Estimates in the Preparation of Financial Statements

The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reporting period. The Company bases estimates on various assumptions that are believed to be reasonable under the circumstances. The Company believes significant judgment was involved in estimating the outsourcing expenses, and in estimating other accrued liabilities and income taxes. Management is continually evaluating and updating these estimates, and it is possible that these estimates will change in the future or that actual results may differ from these estimates.

Cash Equivalents

Cash equivalents generally consist of money market funds and debt securities with maturities of 90 days or less at the time of purchase. The Company invests its excess cash in securities with strong ratings and has established guidelines relative to diversification and maturity with the objective of maintaining safety of principal and liquidity.

Concentrations of Credit Risk

Financial instruments that potentially subject the Company to significant concentrations of credit risk consist primarily of cash and cash equivalents. The Company has no off-balance-sheet concentrations of credit risk, such as foreign exchange contracts, option contracts, or foreign currency hedging arrangements. The Company maintains cash and cash equivalent balances in the form of bank demand deposits and money market fund accounts with financial institutions that management believes are creditworthy. Such balances may at times exceed the insured amount.

Property and Equipment

Property and equipment are stated at cost less accumulated depreciation and amortization. Cost includes expenditures for equipment, leasehold improvements, replacements, and renewals. Maintenance and repairs are charged to expense as incurred. When assets are sold, retired, or otherwise disposed of, the cost and accumulated depreciation are removed from the accounts and any resulting gain or loss is reflected in operations. The cost of property and equipment is depreciated using the straight-line method over the estimated useful lives of the related assets. Leasehold improvements are amortized over the shorter of the life of the lease or the estimated useful life of the assets.

Comprehensive Loss

Comprehensive loss is defined as the change in equity during a period from transactions and other events and/or circumstances from non-owner sources. If the Company had comprehensive gains (losses), they would be reflected in the statement of operations and comprehensive loss and as a separate component in the statement of stockholders’ equity. There were no elements of comprehensive loss during the years ended December 31, 2023 and 2022.

Leases

The Company determines if an arrangement is a lease at inception. Operating leases are included in right-of-use (ROU) asset – operating and lease obligations are included in accrued expenses and other liabilities and operating lease liability on the Company’s December 31, 2023 and 2022 balance sheets.

ROU lease assets represent the Company’s right to use an underlying asset for the lease term and lease obligations represent the Company’s obligation to make lease payments arising from the lease. Operating ROU lease assets are recognized at the commencement date based on the present value of lease payments over the lease term. As the Company’s lease does not provide an implicit rate, the Company uses its incremental borrowing rate based on the information available at the commencement date in determining the present value of lease payments. The Company’s lease terms may include options to extend or terminate the lease when it is reasonably certain that the Company will exercise that option. Lease expense for lease payments is recognized on a straight-line basis over the lease term.

Accrued Outsourcing Expenses

As part of the process of preparing its financial statements, the Company is required to estimate accrued outsourcing expenses. This process involves identifying services that third parties have performed on the Company’s behalf and estimating the level of service performed and the associated cost incurred for these services as of the balance sheet date. Examples of estimated accrued outsourcing expenses include contract service fees, such as fees payable to contract manufacturers in connection with the production of materials related to the Company’s drug product, and service fees and pass through costs from clinical research organizations. The Company develops estimates of liabilities using its judgment based upon the facts and circumstances known at the time.

Segments

The Company operates in one segment. Management uses one measure of profitability and does not segment its business for internal reporting.

Research and Development

Research and development costs are expensed as incurred. These consist primarily of salaries, contract services, and supplies.

Costs, if any, related to clinical trial and drug manufacturing activities are based upon estimates of the services received and related expenses incurred by contract research organizations (CROs), clinical study sites, drug manufacturers, collaboration partners, laboratories, consultants, or otherwise. Related contracts vary significantly in length, and could be for a fixed amount, a variable amount based on actual costs incurred, capped at a certain limit, or for a combination of these elements. Activity levels are monitored through communications with the vendors, including detailed invoices and task completion review, analysis of expenses against budgeted amounts, and pre-approval of any changes in scope of the services to be performed. Certain significant vendors may also provide an estimate of costs incurred but not invoiced on a periodic basis. Expenses related to the CROs and clinical studies, as well as contract drug manufacturers, are primarily based on progress made against specified milestones or targets in each period.

In accordance with certain research and development agreements, the Company is obligated to make certain upfront payments upon execution of the agreement. The Company records these upfront payments as prepaid research and development expenses, which are included in Other current assets or Other assets in the accompanying Balance Sheets. Such payments are recorded to research and development expense as services are performed. The Company evaluates on a quarterly basis whether events and circumstances have occurred that may indicate impairment of remaining prepaid research and development expenses.

Stock-Based Compensation

The Company’s stock-based compensation cost recognized is based on the estimated grant date fair value. The Company recognizes compensation costs for its stock-based awards on a straight-line basis over the requisite service period for the entire award, as adjusted for expected forfeitures.

Income Taxes

The current benefit for income taxes represents actual or estimated amounts payable or refundable on tax returns filed or to be filed each year. Deferred tax assets and liabilities are recognized for the estimated future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases and operating loss and tax credit carryforwards. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in the period that includes the enactment date. The overall change in deferred tax assets and liabilities for the period measures the deferred tax expense or benefit for the period. The measurement of deferred tax assets may be reduced by a valuation allowance based on judgmental assessment of available evidence if deemed more likely than not that some or all of the deferred tax assets will not be realized.

Related Party Arrangements

12 Months Ended

Dec. 31, 2023

Related Party Arrangements

(5) Related Party Arrangements

Transactions with the Company’s President and Chief Executive Officer

The Company has entered into unrestricted research grants with its President and Chief Executive Officer’s academic research laboratory at the University of Colorado. Funding of any unrestricted research grants is contingent upon the Company’s financial condition, and can be deferred or terminated at the Company’s discretion. Total expense under these arrangements for the years ended December 31, 2023 and 2022 was $(91,000) and $432,000, respectively. In December 2023, the Company made a payment of $125,000 for the grant period July 2022 through December 2023 under these arrangements.

- Definition

The entire disclosure for related party transactions. Examples of related party transactions include transactions between (a) a parent company and its subsidiary; (b) subsidiaries of a common parent; (c) and entity and its principal owners; and (d) affiliates.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480990/946-20-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-URI https://asc.fasb.org//1943274/2147480990/946-20-50-5

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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-Publisher FASB
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-Section 50
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org//850/tableOfContent

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
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Reference 13: http://www.xbrl.org/2003/role/disclosureRef
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-Section 50
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483326/850-10-50-1

+ Details

Net Loss Per Share

12 Months Ended

Dec. 31, 2023

Earnings Per Share [Abstract]

Net Loss Per Share

(2) Net Loss Per Share

The Company calculates basic loss per share by dividing net loss by the weighted average common shares outstanding during the period. Diluted loss per share is computed by dividing net loss by the weighted average number of common shares outstanding during the period increased to include, if dilutive, the number of additional common shares that would have been outstanding if the potential common shares had been issued. The Company’s potentially dilutive shares include stock options and restricted stock units.


	Years Ended December 31,
	2023		2022
Potentially dilutive securities, excluded:
Outstanding stock options		616,707		704,960
Unvested restricted stock units		—		91,000
		616,707		795,960