Summary of Significant Accounting Policies (Policies)	3 Months Ended
Mar. 31, 2025
Accounting Policies [Abstract]
Basis of Presentation and Consolidation	Basis of Presentation and Consolidation The unaudited Condensed Consolidated Financial Statements of the Company have been prepared in accordance with GAAP for interim financial information and with the rules and regulations of the U.S. Securities and Exchange Commission. Accordingly, since they are interim statements, they do not include all of the information and notes required by GAAP for complete consolidated financial statements. The Company’s consolidated financial statements reflect the operation of the Company and its wholly owned subsidiary OnKure, Inc. All intercompany balances and transactions among the consolidated entities have been eliminated in consolidation. See Notes 1 and 3 for further discussion. In the opinion of management, all adjustments (consisting of normal recurring accruals) considered necessary for a fair presentation have been included. Results of operations and cash flows for the interim periods presented herein are not necessarily indicative of the results that would be achieved during a full year of operations or in future periods. These unaudited Condensed Consolidated Financial Statements and notes thereto should be read in conjunction with the Consolidated Financial Statements and notes thereto included in the Company’s Form 10-K.
Segment Information	Segment Information The Company operates in one operating segment: clinical research. All equipment and other property and equipment are physically located within the United States. As a result of the adoption of ASU 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures, the Company has presented the three months ended March 31, 2024 amounts consistent with the corresponding 2025 period presentation.
Use of Estimates	Use of Estimates The preparation of the Company’s consolidated financial statements in accordance with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and contingent liabilities at the date of the financial statements, and the reported amounts of expenses during the reporting period. Although these estimates are based on the Company’s knowledge of current events and actions it may take in the future, actual results may ultimately differ from these estimates. The most significant estimates relate to external research and development expenses, and the fair value of stock options and restricted stock units.
Comprehensive Loss	Comprehensive Loss Comprehensive loss is defined as a change in equity during a period from transactions and other events and circumstances from non-owner sources. The Company’s comprehensive loss was the same as its reported net loss for all periods presented.
Research and Development Expenses	Research and Development Expenses Research and development (“R&D”) costs are expensed as incurred in performing research and development activities. The costs include employee-related expense, including salaries, severance, benefits, share-based compensation, costs of research and development activities conducted by third parties on the Company’s behalf, costs to have clinical trial materials manufactured, fees for acquiring and maintaining licenses under third-party license agreements, consulting fees, depreciation, and facilities and overhead costs.
Accrued Research and Development Expenses	Accrued Research and Development Expenses The Company records research and development expenses in the period in which it receives or takes ownership of the applicable goods or when the applicable services are performed. The Company is required to estimate its expenses resulting from its obligations under contracts with vendors, consultants, and contract research organizations, in connection with conducting research and development activities. The financial terms of these contracts are subject to negotiations, vary from contract to contract and may result in payment flows that do not match the periods over which materials or services are provided under such contracts. The Company reflects research and development expenses in its financial statements by matching those expenses with the period in which services and efforts are expended. The Company accounts for these expenses according to the progress of its preclinical studies or clinical trials, as measured by the timing of various aspects of the study or related activities. The Company determines accrual estimates through a review of the underlying contracts along with the preparation of financial models considering discussions with research and other key personnel as to the progress of studies, trials, or other services being conducted. During a study or trial, the Company adjusts its rate of expense recognition if actual results differ from its estimates. Nonrefundable advance payments for goods and services, including fees for process development or manufacturing and distribution of clinical supplies that will be used in future research and development activities, are deferred and recognized as an expense in the period that the related goods are consumed, or services are performed.
Share-Based Compensation	Share-Based Compensation The Company maintains an equity incentive compensation plan under which incentive stock options and nonqualified stock options to purchase common stock, and restricted stock units for common stock, are granted to employees, board of directors, and non-employee consultants. Stock-based compensation cost is measured at the grant date, based on the fair value of the award, and is recognized as expense over the requisite service or performance period. The fair value of stock options granted to employees is estimated using the Black-Scholes option pricing model. The Black-Scholes valuation method requires certain assumptions be used as inputs, such as the fair value of the underlying common stock, expected term of the option before exercise, expected volatility of the Company’s common stock, risk-free interest rate and expected dividend. Options granted have a maximum contractual term of 10 years. The Company has limited historical stock option activity and therefore estimates the expected term of stock options granted using the simplified method, which represents the arithmetic average of the original contractual term of the stock option and its weighted-average vesting term. The expected volatility of stock options is based on the historical volatility of several publicly traded companies in similar stages of clinical development. The Company will continue to apply this process until enough historical information regarding the volatility of its stock price becomes available. The risk-free interest rates used are based on the U.S. Treasury yield in effect at the time of grant for zero-coupon U.S. treasury notes with maturities approximately equal to the expected term of the stock options. The Company has historically not declared or paid any dividends and does not currently expect to do so in the foreseeable future, and therefore has estimated the dividend yield to be zero. (See Note 10). The Company recognizes stock-based compensation expense for grants under its various equity incentive plans and employee stock purchase plan. The Company accounts for all stock-based awards granted to employees and directors at their fair value and recognizes compensation expense over the award’s vesting period. Determining the amount of stock-based compensation to be recorded requires the Company to develop estimates of fair values of stock options as of the grant date. The Company calculates the grant date fair values of stock options using the Black-Scholes valuation model, which requires the input of subjective assumptions, including but not limited to expected stock price volatility over the term of the awards and the expected term of stock options. The fair value of restricted stock awards granted to employees is based on the quoted closing market price per share on grant date.
Fair Value of Financial Instruments	Fair Value of Financial Instruments The Company is required to disclose information on all assets and liabilities reported at fair value that enables an assessment of the inputs used in determining the reported fair values. The carrying amounts of the Company’s financial assets and liabilities, such as cash, receivables, prepaid and other current assets, accounts payable, and accrued expenses approximate their fair values because of the short maturity of these instruments.
Cash and Cash Equivalents	Cash and Cash Equivalents All highly liquid investments with maturities of 90 days or less, at the time of purchase, are classified as cash equivalents. Cash equivalents are reported at cost, which approximates fair value. The Company’s cash and cash equivalents consist of money held in demand depository accounts and money market funds. The carrying amount of cash and cash equivalents was $96.7 million and $110.8 million as of March 31, 2025 and December 31, 2024, respectively, which approximates fair value and was determined based upon Level 1 inputs. The money market account is valued using quoted market prices with no valuation adjustments applied and is categorized as Level 1.
Concentration of Credit Risk	Concentration of Credit Risk Financial instruments that potentially subject the Company to concentrations of credit risk consist primarily of cash and cash equivalents. The Company maintains accounts in federally insured financial institutions. At times, amounts held in federally insured accounts are above the federally insured limit of $250,000. Management believes the Company is not exposed to significant credit risk due to the financial position of the depository institutions in which these deposits are held and of the money market funds in which these investments are made.
Leasing - Lessee Accounting	Leasing – Lessee Accounting The Company determines if an arrangement is a lease at inception. The Company’s operating lease agreements are primarily for office space and research labs. For operating leases with a term greater than one year, the Company recognizes the right-of-use (“ROU”) assets and lease liabilities related to the lease payments on its balance sheet. The lease liabilities are initially and subsequently measured at the present value of the unpaid lease payments at the lease commencement date. The ROU assets represent the Company’s right to use the underlying assets for the term of the lease and the lease liabilities represent the Company’s obligation to make lease payments arising for the agreements. ROU assets are initially measured at cost, which comprises the initial amount of the lease liability adjusted for lease payments made at or before the lease commencement date, plus any initial direct costs incurred less any lease incentives received. The ROU asset is periodically reviewed for impairment unless a triggering event occurs. Lease expense for lease payments is recognized on a straight-line basis over the lease term. Variable lease payments, except for the ones that depend on index or rate, are excluded from the calculation of the ROU assets and lease liabilities and are recognized as variable lease expense in the statements of operations and comprehensive loss in the period in which they are incurred. Sublease inflows are netted against the respective lease outflows. As the interest rate implicit in the Company’s leases is not readily determinable, the Company uses its estimated incremental borrowing rate in its present value calculations. One of the Company’s lessee agreements include an option to extend the lease, which the Company does not include in its minimum lease term unless it is reasonably certain to exercise such option. Operating leases with a term of less than one year are recognized as a lease expense over the term of the lease, with no asset or liability recognized on the balance sheet.
Recently Issued Accounting Pronouncements	Recently Issued Accounting Pronouncements In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures (“ASU 2023-09”), which requires enhanced income tax disclosures, including specific categories and disaggregation of information in the effective tax rate reconciliation, disaggregated information related to income taxes paid, income or loss from continuing operations before income tax expense or benefit, and income tax expense or benefit from continuing operations. The requirements of the ASU are effective for annual periods beginning after December 15, 2024, with early adoption permitted. This ASU may be applied either prospectively or retrospectively. The Company is currently evaluating the impact of this pronouncement. In November 2024, the FASB issued ASU 2024-03, Income Statement—Reporting Comprehensive Income—Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses. This ASU requires more detailed disclosures, on an annual and interim basis, about specified categories of expenses (including employee compensation, depreciation, and amortization) included in certain expense captions presented on the face of the income statement. This ASU is effective for fiscal years beginning after December 15, 2026, and interim periods within fiscal years beginning after December 15, 2027. Early adoption is permitted. This ASU may be applied either prospectively or retrospectively. The Company is currently evaluating the impact of this pronouncement. The Company continues to monitor new accounting pronouncements issued by the FASB and does not believe any accounting pronouncements issued through the date of this report will have a material impact on its financial statements.

Summary of Significant Accounting Policies (Policies)

3 Months Ended

Mar. 31, 2025

The unaudited Condensed Consolidated Financial Statements of the Company have been prepared in accordance with GAAP for interim financial information and with the rules and regulations of the U.S. Securities and Exchange Commission. Accordingly, since they are interim statements, they do not include all of the information and notes required by GAAP for complete consolidated financial statements. The Company’s consolidated financial statements reflect the operation of the Company and its wholly owned subsidiary OnKure, Inc. All intercompany balances and transactions among the consolidated entities have been eliminated in consolidation. See Notes 1 and 3 for further discussion.

In the opinion of management, all adjustments (consisting of normal recurring accruals) considered necessary for a fair presentation have been included. Results of operations and cash flows for the interim periods presented herein are not necessarily indicative of the results that would be achieved during a full year of operations or in future periods. These unaudited Condensed Consolidated Financial Statements and notes thereto should be read in conjunction with the Consolidated Financial Statements and notes thereto included in the Company’s Form 10-K.

Segment Information

The Company operates in one operating segment: clinical research. All equipment and other property and equipment are physically located within the United States. As a result of the adoption of ASU 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures, the Company has presented the three months ended March 31, 2024 amounts consistent with the corresponding 2025 period presentation.

Use of Estimates

The preparation of the Company’s consolidated financial statements in accordance with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and contingent liabilities at the date of the financial statements, and the reported amounts of expenses during the reporting period. Although these estimates are based on the Company’s knowledge of current events and actions it may take in the future, actual results may ultimately differ from these estimates. The most significant estimates relate to external research and development expenses, and the fair value of stock options and restricted stock units.

Comprehensive Loss

Comprehensive loss is defined as a change in equity during a period from transactions and other events and circumstances from non-owner sources. The Company’s comprehensive loss was the same as its reported net loss for all periods presented.

Research and Development Expenses

Research and development (“R&D”) costs are expensed as incurred in performing research and development activities. The costs include employee-related expense, including salaries, severance, benefits, share-based compensation, costs of research and development activities conducted by third parties on the Company’s behalf, costs to have clinical trial materials manufactured, fees for acquiring and maintaining licenses under third-party license agreements, consulting fees, depreciation, and facilities and overhead costs.

Accrued Research and Development Expenses

The Company records research and development expenses in the period in which it receives or takes ownership of the applicable goods or when the applicable services are performed. The Company is required to estimate its expenses resulting from its obligations under contracts with vendors, consultants, and contract research organizations, in connection with conducting research and development activities. The financial terms of these contracts are subject to negotiations, vary from contract to contract and may result in payment flows that do not match the periods over which materials or services are provided under such contracts. The Company reflects research and development expenses in its financial statements by matching those expenses with the period in which services and efforts are expended. The Company accounts for these expenses according to the progress of its preclinical studies or clinical trials, as measured by the timing of various aspects of the study or related activities. The Company determines accrual estimates through a review of the underlying contracts along with the preparation of financial models considering discussions with research and other key personnel as to the progress of studies, trials, or other services being conducted. During a study or trial, the Company adjusts its rate of expense recognition if actual results differ from its estimates. Nonrefundable advance payments for goods and services, including fees for process development or manufacturing and distribution of clinical supplies that will be used in future research and development activities, are deferred and recognized as an expense in the period that the related goods are consumed, or services are performed.

Share-Based Compensation

The Company maintains an equity incentive compensation plan under which incentive stock options and nonqualified stock options to purchase common stock, and restricted stock units for common stock, are granted to employees, board of directors, and non-employee consultants. Stock-based compensation cost is measured at the grant date, based on the fair value of the award, and is recognized as expense over the requisite service or performance period. The fair value of stock options granted to employees is estimated using the Black-Scholes option pricing model.

The Black-Scholes valuation method requires certain assumptions be used as inputs, such as the fair value of the underlying common stock, expected term of the option before exercise, expected volatility of the Company’s common stock, risk-free interest rate and expected dividend. Options granted have a maximum contractual term of 10 years. The Company has limited historical stock option activity and therefore estimates the expected term of stock options granted using the simplified method, which represents the arithmetic average of the original contractual term of the stock option and its weighted-average vesting term. The expected volatility of stock options is based on the historical volatility of several publicly traded companies in similar stages of clinical development. The Company will continue to apply this process until enough historical information regarding the volatility of its stock price becomes available. The risk-free interest rates used are based on the U.S. Treasury yield in effect at the time of grant for zero-coupon U.S. treasury notes with maturities approximately equal to the expected term of the stock options. The Company has historically not declared or paid any dividends and does not currently expect to do so in the foreseeable future, and therefore has estimated the dividend yield to be zero. (See Note 10).

The Company recognizes stock-based compensation expense for grants under its various equity incentive plans and employee stock purchase plan. The Company accounts for all stock-based awards granted to employees and directors at their fair value and recognizes compensation expense over the award’s vesting period. Determining the amount of stock-based compensation to be recorded requires the Company to develop estimates of fair values of

stock options as of the grant date. The Company calculates the grant date fair values of stock options using the Black-Scholes valuation model, which requires the input of subjective assumptions, including but not limited to expected stock price volatility over the term of the awards and the expected term of stock options. The fair value of restricted stock awards granted to employees is based on the quoted closing market price per share on grant date.

Fair Value of Financial Instruments

The Company is required to disclose information on all assets and liabilities reported at fair value that enables an assessment of the inputs used in determining the reported fair values.

The carrying amounts of the Company’s financial assets and liabilities, such as cash, receivables, prepaid and other current assets, accounts payable, and accrued expenses approximate their fair values because of the short maturity of these instruments.

Cash and Cash Equivalents

All highly liquid investments with maturities of 90 days or less, at the time of purchase, are classified as cash equivalents. Cash equivalents are reported at cost, which approximates fair value. The Company’s cash and cash equivalents consist of money held in demand depository accounts and money market funds. The carrying amount of cash and cash equivalents was $96.7 million and $110.8 million as of March 31, 2025 and December 31, 2024, respectively, which approximates fair value and was determined based upon Level 1 inputs. The money market account is valued using quoted market prices with no valuation adjustments applied and is categorized as Level 1.

Concentration of Credit Risk

Financial instruments that potentially subject the Company to concentrations of credit risk consist primarily of cash and cash equivalents. The Company maintains accounts in federally insured financial institutions. At times, amounts held in federally insured accounts are above the federally insured limit of $250,000. Management believes the Company is not exposed to significant credit risk due to the financial position of the depository institutions in which these deposits are held and of the money market funds in which these investments are made.

Leasing - Lessee Accounting

Leasing – Lessee Accounting

The Company determines if an arrangement is a lease at inception. The Company’s operating lease agreements are primarily for office space and research labs.

For operating leases with a term greater than one year, the Company recognizes the right-of-use (“ROU”) assets and lease liabilities related to the lease payments on its balance sheet. The lease liabilities are initially and subsequently measured at the present value of the unpaid lease payments at the lease commencement date. The ROU assets represent the Company’s right to use the underlying assets for the term of the lease and the lease liabilities represent the Company’s obligation to make lease payments arising for the agreements. ROU assets are initially measured at cost, which comprises the initial amount of the lease liability adjusted for lease payments made at or before the lease commencement date, plus any initial direct costs incurred less any lease incentives received. The ROU asset is periodically reviewed for impairment unless a triggering event occurs. Lease expense for lease payments is recognized on a straight-line basis over the lease term. Variable lease payments, except for the ones that depend on index or rate, are excluded from the calculation of the ROU assets and lease liabilities and are recognized as variable lease expense in the statements of operations and comprehensive loss in the period in which they are incurred. Sublease inflows are netted against the respective lease outflows.

As the interest rate implicit in the Company’s leases is not readily determinable, the Company uses its estimated incremental borrowing rate in its present value calculations. One of the Company’s lessee agreements include an option to extend the lease, which the Company does not include in its minimum lease term unless it is reasonably certain to exercise such option. Operating leases with a term of less than one year are recognized as a lease expense over the term of the lease, with no asset or liability recognized on the balance sheet.

Recently Issued Accounting Pronouncements

In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures (“ASU 2023-09”), which requires enhanced income tax disclosures, including specific categories and disaggregation of information in the effective tax rate reconciliation, disaggregated information related to income taxes paid, income or loss from continuing operations before income tax expense or benefit, and income tax expense or benefit from continuing operations. The requirements of the ASU are effective for annual periods

beginning after December 15, 2024, with early adoption permitted. This ASU may be applied either prospectively or retrospectively. The Company is currently evaluating the impact of this pronouncement.

In November 2024, the FASB issued ASU 2024-03, Income Statement—Reporting Comprehensive Income—Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses. This ASU requires more detailed disclosures, on an annual and interim basis, about specified categories of expenses (including employee compensation, depreciation, and amortization) included in certain expense captions presented on the face of the income statement. This ASU is effective for fiscal years beginning after December 15, 2026, and interim periods within fiscal years beginning after December 15, 2027. Early adoption is permitted. This ASU may be applied either prospectively or retrospectively. The Company is currently evaluating the impact of this pronouncement.

The Company continues to monitor new accounting pronouncements issued by the FASB and does not believe any accounting pronouncements issued through the date of this report will have a material impact on its financial statements.