Prelude Therapeutics Inc

1. Nature of Operations

Prelude Therapeutics Incorporated (the “Company”) is a clinical-stage fully integrated oncology company built on a foundation of drug discovery excellence to deliver novel precision cancer medicines to underserved patients. Since beginning operations in 2016, the Company has devoted substantially all its efforts to research and development, conducting preclinical and clinical studies, recruiting management and technical staff, administration, and raising capital.

2. Risks and Liquidity

The Company is subject to a number of risks common to early-stage companies in the biotechnology industry. Principal among these risks are the uncertainties in the development process, development of the same or similar technological innovations by competitors, protection of proprietary technology, dependence on key personnel, compliance with government regulations and approval requirements, and the need to obtain additional financing to fund operations. Product candidates currently under development will require significant additional research and development efforts, including extensive pre-clinical and clinical testing and regulatory approval, prior to commercialization. These efforts require significant amounts of additional capital, adequate personnel infrastructure, and extensive compliance-reporting capabilities. There can be no assurance that the Company’s research and development will be successfully completed, that adequate protection for the Company’s technology will be obtained, that any products developed will obtain necessary government regulatory approval, or that any approved products will be commercially viable. The Company operates in an environment of rapid change in technology and substantial competition from pharmaceutical and biotechnology companies. In addition, the Company is dependent upon the services of its employees, consultants and contractors.

Since its inception, the Company has incurred operating losses and had an accumulated deficit of$456.4 million at December 31, 2023. The Company has no revenue to date and devotes its efforts to research and development. The Company anticipates incurring additional losses until such time, if ever, that it can generate significant sales of its product candidates currently in development.

The Company believes that its cash, cash equivalents and marketable securities as of December 31, 2023 will be sufficient to fund its operating expenses and capital expenditure requirements into 2026.

To fund its operating expenses and capital expenditure requirements after that date, the Company plans to seek additional funding through public or private equity offerings, debt financings, collaborations, strategic alliances and licensing arrangements. The Company may not be able to obtain financing on acceptable terms, or at all, and the Company may not be able to enter into strategic alliances or other arrangements on favorable terms, or at all. The terms of any financing may adversely affect the holdings or the rights of the Company’s stockholders. If the Company is unable to obtain funding, the Company could be required to delay, reduce or eliminate research and development programs, product portfolio expansion or future commercialization efforts, which could adversely affect its business prospects.

3. Summary of Significant Accounting Policies

Basis of Presentation

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

Use of Estimates

The preparation of financial statements in conformity 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. Actual results could differ from those estimates.

Estimates and assumptions are periodically reviewed, and the effects of the revisions are reflected in the accompanying financial statements in the period they are determined to be necessary. The most significant estimate relates to accrued clinical trial expenses.

Concentration of Credit Risk

Financial instruments that potentially subject the Company to significant concentrations of credit risk consist of cash, cash equivalents, and marketable securities. The Company maintains deposits in federally insured financial institutions in excess of federally insured limits. The Company has not experienced any losses in such accounts and believes it is not exposed to significant credit risk beyond the normal credit risk associated with commercial banking relationships.

Segment Information

Operating segments are defined as components of an enterprise about which separate discrete information is available for evaluation by the chief operating decision maker, or decision-making group, in deciding how to allocate resources and in assessing performance. The Company views and manages its operations as a single operating segment.

Fair Value of Financial Instruments

Management believes that the carrying amounts of the Company’s financial instruments, including cash, restricted cash, accounts payable, and accrued expenses, approximate fair value due to the short-term nature of these instruments.

Cash, Cash Equivalents and Restricted cash

The Company’s cash equivalents include short-term highly liquid investments with an original maturity of 90 days or less when purchased and are carried at fair value in the accompanying balance sheets.

Restricted cash comprises a letter of credit with Silicon Valley Bank for the benefit of the landlord in connection with the Company’s new lease facility. See Note 8 (Commitments) for further details.

The following table provides a reconciliation of cash and cash equivalents and restricted cash reported within the balance sheet that total to the amounts shown in the statement of cash flows:

Marketable Securities

The Company’s marketable securities consist of investments in corporate debt securities, United States, or U.S., government debt securities, and agency securities that are classified as available-for-sale. The securities are carried at fair value with the unrealized gains and losses, net of tax, included in accumulated other comprehensive income (loss), a component of stockholders’ equity. Realized gains and losses as well as credit losses, if any, on marketable securities are included in the Company’s statements of operations. The Company classifies marketable securities that are available for use in current operations as current assets on the balance sheets.

Property and Equipment

Property and equipment are stated at cost less accumulated depreciation and amortization. Depreciation expense is recognized using the straight-line method over the estimated useful life of the asset, ranging from 5-7 years as follows:

Leasehold improvements are amortized over the shorter of the estimated useful life of the assets or the remaining lease term.

Expenditures for repairs and maintenance of assets are charged to expense as incurred, while major betterments are capitalized. Upon retirement or sale, the cost and related accumulated depreciation of assets disposed of are removed from the accounts and any resulting gain or loss is included in the statements of operations.

The Company reviews long-lived assets, such as property and equipment, for impairment when events or changes in circumstances indicate the carrying amount of the assets may not be recoverable. If indicators of impairment are present, the assets are tested for recoverability by comparing the carrying amount of the assets to the related estimated future undiscounted cash flows that the assets are expected to generate. If the expected cash flows are less than the carrying value of the asset, then the asset is considered to be impaired and its carrying value is written down to fair value, based on the related estimated discounted future cash flows.

Leases

The Company accounts for leases in accordance with ASC Topic 842, Leases. The Company's lease for office and laboratory space located in Wilmington, DE is classified as an operating lease. The lease results in an operating right-of-use (ROU) asset, a current operating lease liability, and a non-current operating lease liability in the balance sheet and has a remaining lease term of 162 months. The Company does not have any financing leases. Leases with a term of 12 months or less are considered short-term and a ROU asset and lease obligation are not recognized.

ROU assets represent the right to use an underlying asset for the lease term and the lease liabilities represent an obligation to make lease payments arising from the lease, measured at the present value of the lease payments not yet paid discounted using the discount rate for the lease established at the lease commencement date. The operating lease ROU asset also includes any prepaid lease payments made. Lease expense is recognized over the expected lease term on a straight-line basis.

Comprehensive loss

Comprehensive loss includes net loss and certain changes in stockholders’ equity that are excluded from net loss. The Company’s comprehensive loss for the years ended December 31, 2023 and 2022 comprised net loss and unrealized gain or loss on marketable securities.

Stock-Based Compensation

The Company measures share-based awards at their grant-date fair value and records compensation expense on a straight-line basis over the vesting period of the awards.

Estimating the fair value of share-based awards requires the input of subjective assumptions, including, for stock options, the expected life of the options and stock price volatility. The Company accounts for forfeitures for stock option awards as they occur. The Company uses the Black-Scholes option pricing model to value its stock option awards. The assumptions used in estimating the fair value of share-based awards represent management’s estimate and involve inherent uncertainties and the application of management’s judgment. As a result, if factors change and management uses different assumptions, share-based compensation expense could be materially different for future awards.

The expected life of the stock options is estimated using the “simplified method”, as the Company has limited historical information from which to develop reasonable expectations about future exercise patterns and post-vesting employment termination behavior for its stock option grants. The simplified method is the midpoint between the vesting period and the contractual term of the option. For stock price volatility, the Company uses its own historical volatility along with comparable public companies as a basis for its expected volatility to calculate the fair value of option grants. The risk-free rate is based on the U.S. Treasury yield curve commensurate with the expected life of the option.

Grant Income and Research and Development Tax Credits

The Company recognizes grants related to income and Delaware research and development tax credits in other income, net in the statements of operations when the necessary qualifying conditions, as stated in the agreements, are met and all contingencies have been resolved. For the years ended December 31, 2023 and 2022, the Company recorded other income of $1.5 million and $6.1 million, respectively. The Company recognizes grants related to assets as deferred income on the balance sheet. The deferred income is then recognized as grant income over the useful life of the related assets.

Research and Development

Research and development costs are expensed as incurred. Research and development expenses consist principally of personnel costs, including salaries, stock-based compensation, and benefits of employees, and other operational costs related to the Company’s research and development activities, including allocated facility-related expenses and external costs of outside vendors, such as clinical research organizations and clinical manufacturing organizations, and other direct and indirect costs.

Management makes estimates of the Company’s accrued research and development expenses as of each balance sheet date in the Company’s financial statements based on facts and circumstances known to the Company at that time. If the actual timing of the performance of services or the level of effort varies from the estimate, the Company will adjust the accrual accordingly. 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 expense in the period that the related goods are consumed or services are performed.

Income Taxes

Income taxes are accounted for under the asset-and-liability method as required by FASB ASC Topic 740, Income Taxes (“ASC 740”). Deferred tax assets and liabilities are recognized for the 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. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period corresponding to the enactment date. Under ASC 740, a valuation allowance is required when it is more likely than not all or some portion of the deferred tax assets will not be realized through generating sufficient future taxable income.

FASB ASC Subtopic 740-10, Accounting for Uncertainty of Income Taxes, (“ASC 740-10”) defines the criterion an individual tax position must meet for any part of the benefit of the tax position to be recognized in financial statements prepared in conformity with GAAP. The Company may recognize the tax benefit from an uncertaintax position only if it is more likely than not such tax position will be sustained on examination by the taxing authorities, based solely on the technical merits of the respective tax position. The tax benefits recognized in the financial statements from such a tax position should be measured based on the largest benefit having a greater than 50% likelihood of being realized upon ultimate settlement with the tax authority. In accordance with the disclosure requirements of ASC 740-10, the Company’s policy on income statement classification of interest and penalties related to income tax obligations is to include such items as a component of income tax expense.

Net Loss Per Share

Basic net loss per share of common stock is computed by dividing net loss by the weighted-average number of shares of common stock outstanding during each period, including pre-funded warrants to purchase shares of common stock that were issued in a financing transaction in 2023 (Note 9). The weighted-average number of shares of common stock outstanding used in the basic net loss per share calculation does not include unvested restricted stock awards as these instruments are considered contingently issuable shares until they vest. Diluted net loss per share of common stock includes the effect, if any, from the potential exercise of securities, such as stock options, and the effect from unvested restricted stock awards and restricted stock units which would result in the issuance of incremental shares of common stock. For diluted net loss per share, the weighted-average number of shares of common stock is the same for basic net loss per share due to the fact that when a net loss exists, dilutive securities are not included in the calculation as the impact is anti-dilutive. The Company’s unvested restricted stock awards entitle the holder to participate in dividends and earnings of the Company, and, if the Company were to recognize net income, it would have to use the two-class method to calculate earnings per share. The two-class method is not applicable during periods with a net loss, as the holders of the unvested restricted stock awards have no obligation to fund losses.

The following potentially dilutive securities have been excluded from the computation of diluted weighted-average shares of common stock outstanding, as they would be anti-dilutive:

Amounts in the above table reflect the common stock equivalents.

Recently Issued Accounting Pronouncements

Emerging Growth Company Status

The Company is an emerging growth company, as defined in the Jumpstart Our Business Startups Act of 2012 (the “JOBS Act”). Under the JOBS Act, emerging growth companies can delay adopting new or revised accounting standards issued subsequent to the enactment of the JOBS Act, until such time as those standards apply to private companies. The Company has elected to use this extended transition period for complying with new or revised accounting standards that have different effective dates for public and private companies until the earlier of the date that it (i) is no longer an emerging growth company or (ii) affirmatively and irrevocably opts out of the extended transition period provided in the JOBS Act. The Company will remain an emerging growth company until the earliest of (i) the last day of the Company's first fiscal year (a) in which the Company has total annual gross revenues of at least $1.235 billion, or (b) in which the Company is deemed to be a large accelerated filer, which means the market value of the Company's common stock that is held by non-affiliates exceeds $700.0 million as of the prior June 30, (ii) the date on which the Company has issued more than $1.0 billion in non-convertible debt securities during the prior three-year period and (iii) December 31, 2025. As a result, these financial statements may not be comparable to companies that comply with the new or revised accounting pronouncements as of public company effective dates.

Recently Adopted Accounting Pronouncements

In August 2020, the FASB issued ASU Update No. 2020-06, Debt — Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging — Contracts in Entity’s Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity (ASU 2020-06)(“ASU 2020-06”). ASU 2020-06 eliminated the beneficial conversion and cash conversion accounting models in ASC 470-20 which required separate accountingfor embedded conversion features and simplified the settlement assessment to determine whether an instrument qualifies for equity classification. The Company early adopted the new standard on January 1, 2023. The adoption did not have a material impact on the financial statements.

Accounting guidance not yet adopted

In December 2023, the FASB issued ASU Updated No. 2023-09, Income Taxes - Improvements to Income Tax Disclosures. ASU 2023-09 requires enhanced income tax disclosures related to the rate reconciliation and income taxes paid information. For public business entities, the amendments in this Update are effective for annual periods beginning after December 15, 2024 with early adoption permitted. The Company is currently evaluating the impact of this standard but does not expect that it will have a material impact on the financial statements and related disclosures.

4. Marketable Securities

The following is a summary of the Company’s marketable securities as of December 31, 2023 and 2022.

The Company’s marketable securities generally have contractual maturity dates of 21 months or less. As of December 31, 2023, the Company had 19 securities with a total fair market value of $75.6 million in an unrealized loss position. The Company believes that any unrealized losses associated with the decline in value of its securities is temporary and is primarily related to the change in market interest rates since purchase and believes that it is more likely than not that it will be able to hold its debt securities to maturity.

5. Fair Value of Financial Instruments

Fair value is the price that could be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. Fair value determination in accordance with applicable accounting guidance requires that a number of significant judgments be made. Additionally, fair value is used on a nonrecurring basis to evaluate assets for impairment or as required for disclosure purposes by applicable accounting guidance on disclosures about fair value of financial instruments. Depending on the nature of the assets and liabilities, various valuation techniques and assumptions are used when estimating fair value. The Company follows the provisions of ASC 820, Fair Value Measurement, for financial assets and liabilities measured on a recurring basis. The guidance requires fair value measurements be classified and disclosed in one of the following three categories:

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Level 1: Unadjusted quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities.

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Level 2: Quoted prices in markets that are not active, or inputs which are observable, either directly or indirectly, for substantially the full term of the asset or liabilities.

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Level 3: Prices or valuation techniques that require inputs that are both significant to the fair value measurement and unobservable (i.e., supported by little or no market activity).

The following fair value hierarchy table presents information about the Company’s assets and liabilities measured at fair value on a recurring basis:

6. Property and Equipment

Property and equipment consisted of the following:

7. Accrued Expenses and Other Current Liabilities

Accrued expenses and other current liabilities consisted of the following:

8. Commitments

Leases

The Company leased office and laboratory space in Wilmington, Delaware under a noncancelable lease (the “Lease”) for which the lease term ended on December 31, 2023. The discount rate used to account for the Company’s operating lease under ASC 842, Leases, was the Company’s estimated incremental borrowing rate of 9.5%.

In 2021, the Company entered into a lease agreement for office and lab space at Chestnut Run Plaza in Wilmington, Delaware (the “Chestnut Run Lease”). The premises includes approximately 81,000 rentable square feet and has an initial term of 162 months with 3 five-year extension options and certain expansion rights. Neither the option to extend nor the expansion rights were recognized as part of the Company's measurement of the ROU asset and operating lease liability as of December 31, 2023. Under the terms of the Chestnut Run Lease, the landlord provided an allowance towards the cost of completing tenant improvements for the premises. The Company concluded that the improvements resulting from both the landlord's build-out and the tenant improvements are the landlord's assets for accounting purposes. Costs incurred by the Company related to tenant improvements in excess of the landlord's allowance have been treated as prepaid rent and increased the right-of-use asset on the commencement date. The Chestnut Run Lease commenced for accounting purposes in December 2023 when the Company took control of the leased space. On the commencement date, the Company recorded approximately $30.6 million and $16.7 million of right-of-use asset and lease liability, respectively. The right-of-use asset includes approximately $13.9 million related to prepaid rent which was reclassified from long-term prepaid assets. The discount rate used to account for the Company’s operating lease under ASC 842, Leases, is the Company’s estimated incremental borrowing rate of 15.0%. The Company's incremental borrowing rate reflects a collateralized borrowing with a similar term and amount as the Chestnut Run Lease.

Lease cost for the year ended December 31, 2023 was $2.5 million, including $0.2 million of short-term lease cost. Lease cost for the year ended December 31, 2022 was $2.1 million, including $0.3 million of short-term lease cost. Cash paid for amounts included in the measurement of operating lease liabilities for the years ended December 31, 2023 and 2022 was $1.9 million and $1.8 million, respectively.

As of December 31, 2023 the estimated rent payments related to the Chestnut Run Lease are as follows:

The Company paid a security deposit in the form of a letter of credit with Silicon Valley Bank of $4.0 million which is included in the balance sheet as restricted cash as of December 31, 2023 and 2022. The security deposit may be reduced to $0.5 million over time in accordance with the terms of the Chestnut Run Lease.

In connection with the Company’s expansion of operations in the State of Delaware, the Company was approved for a grant from the State of Delaware in 2021 that will provide up to $5.5 million in reimbursements over three years for the development of lab space in addition to increasing jobs in Delaware to meet specific targeted levels through 2023. During the third quarter of 2022, the Company was approved for an additional grant from the State of Delaware for the development of lab space in the amount of $1.0 million. In 2022, the Company received cash of $3.4 million from the grants for the development of lab space. The Company has met the minimum requirements stated in the grant agreement in order to not be required to pay back any portion of the $3.4 million disbursed. The Company has deferred the recognition of these grant funds as they relate to capitalized costs and has classified them as long-term liabilities on the balance sheet. In December 2023, the Company began to recognize the grant funds in other income and will continue to do so over the useful life of the related assets. If the Company leaves the State of Delaware within five years of the disbursement, the Company is required to return an amount equal to the amount of grant funds disbursed on a pro-rated basis.

Employment Agreements

The Company entered into employment agreements with key personnel providing for compensation and severance in certain circumstances, as defined in the respective employment agreements.

401(k) Defined Contribution Plan

The Company sponsors a 401(k) defined‑contribution plan covering all employees. Participants are permitted to contribute up to 100% of their eligible annual pretax compensation up to an established federal limit on aggregate participant contributions. The Company provides a match with a maximum amount of 3% of the participant’s compensation. During the years ended December 31, 2023 and 2022 the Company made matching contributions of $0.7 million and $0.6 million, respectively.

Research Collaboration Agreement

In November 2023, the Company entered into a multi-year, multi-program agreement with AbCellera to jointly discover, develop, and commercialize novel oncology medicines for up to five programs. Under the terms of the agreement, AbCellera will lead manufacturing activities and the Company will lead clinical development and global commercialization, subject to AbCellera’s option to co-promote any resulting commercial products in the United States. If, at any point one party in the collaboration opts-out of future co-development cost sharing, that party will be entitled to a royalty from commercialization of the collaboration target, dependent on the proportion of their co-development contributions compared to the total development costs of a target as defined within the agreement. The Company concluded that the agreement with AbCellera will be accounted for under the scope of ASC 808 as both parties will actively participate in joint operating activities and are exposed to significant risks and rewards. Under ASC 808, certain transactions between collaborative arrangement participants should follow the accounting for revenue under ASC 606 when the collaborative arrangement participant is a customer for a distinct good or service. The Company determined that co-development arrangement as defined in our agreement with AbCellera does not meet the definition of a customer as defined by ASC 606. As a result, these activities will be accounted for as research and development costs. Costs related to the AbCellera collaboration were not material for the year ended December 31, 2023.

Other Research and Development Arrangements

The Company enters into agreements with CROs to assist in the performance of research and development activities. Expenditures to CROs will represent a significant cost in clinical development for the Company.

9. Common Stock

The Company has two classes of common stock; “voting common stock” and “non-voting common stock.”The holders of the voting common stock are entitled to one vote for each share of voting common stock held at all meetings of stockholders. Except as otherwise required by law, the holders of non-voting common stock shall not be entitled to vote at any meetings of stockholders (or written actions in lieu of meetings) and the shares of non-voting common stock shall not be included in determining the number of shares voting or entitled to vote on any matter. Unless required by law, there shall be no cumulative voting. Any holder of non-voting common stock may elect to convert each share of non-voting common stock into one fully paid and non-assessable share of voting common stock at any time by providing written notice to the Company; provided that as a result of such conversion, such holder, together with its affiliates and any members of a Schedule 13(d) group with such holder, would not beneficially own in excess of 9.99% of the Company’s common stock immediately prior to and following such conversion, unless otherwise as expressly provided for in the Company’s restated certificate of incorporation. However, this ownership limitation may be increased (not to exceed 19.99%) or decreased to any other percentage designated by such holder of non-voting common stock upon 61 days’ notice to the Company.

2023 financings

During the second quarter of 2023, the Company sold 6,761,200 shares of its common stock which comprised of (i)5,312,978 shares of its voting common stock and (ii)1,448,222 shares of its non-voting common stock at a price of $5.75 per share and to certain investors in lieu of common stock, the Company sold pre-funded warrants to purchase 12,895,256 shares of voting common stock at a price of $5.7499 per pre-funded warrant, resulting in gross proceeds to the Company of $113.0 million. Of the voting common stock issued,2,264,456 shares were purchased by the Company’s underwriters in connection with a 30-day option at a price of $5.75 per share. Offering costs of $2.6 million, of which $0.3 million were previously paid and deferred, were recorded to additional paid-in capital in the accompanying balance sheets, resulting in net proceeds of $110.4 million.

During the fourth quarter of 2023, the Company sold in a private placement pre-funded warrants to purchase 7,936,759 shares of voting common stock at a price of $3.1499 per pre-funded warrant, resulting in net proceeds of $24.8 million after deducting offering costs of $0.2 million.

The purchase price per share of each pre-funded warrant represents the per share offering price for the common stock, minus the $0.0001 per share exercise price of such pre-funded warrant. As of December 31, 2023, no pre-funded warrants had been exercised.

The pre-funded warrants were classified as a component of permanent stockholders’ equity within additional paid-in capital and were recorded at the issuance date using a relative fair value allocation method. The pre-funded warrants are equity classified because they (i) are freestanding financial instruments that are legally detachable and separately exercisable from the equity instruments, (ii) are immediately exercisable, (iii) do not embody an obligation for the Company to repurchase its shares, (iv) permit the holders to receive a fixed number of shares of common stock upon exercise, (v) are indexed to the Company’s common stock and (vi) meet the equity classification criteria. In addition, such pre-funded warrants do not provide any guarantee of value or return.

10. Stock-Based Compensation

The Company hastwo equity incentive plans: the 2016 Equity Incentive Plan, as amended, and the 2020 Equity Incentive Plan. New awards can only be granted under the 2020 Equity Incentive Plan (the “Plan”). The total number of shares initially authorized under the Plan was 4,680,000, which was increased on January 1, 2021 and will automatically increase on January 1st of each year, continuing forten years, in an amount equal tofive percent of the total number of shares of the Company’s common stock outstanding on December 31st of the preceding calendar year, subject to the discretion of the board of directors or compensation committee to determine a lesser number of shares shall be added for such year. At December 31, 2023,4,999,564 shares were available for future grants and on January 1, 2024,2,745,712 shares were added to the Plan. The Plan provides for the granting of common stock, incentive stock options, nonqualified stock options, restricted stock awards, restricted stock units and/or stock appreciation rights to employees, directors, and other persons, as determined by the Company’s board of directors. The Company’s stock options vest based on the terms in each award agreement, generally over four-year periods with 25% of options vesting after 1 year and then monthly thereafter, and have a term often years.

The Company measures stock-based awards at their grant-date fair value and records compensation expense on a straight-line basis over the vesting period of the awards. The Company recorded stock-based compensation expense in the following expense categories in its accompanying statements of operations:

Stock Options

The following table summarizes stock option activity for the Plan in the years indicated:

The aggregate intrinsic value of options exercised was $0.1 million and $1.1 million during the year ended December 31, 2023 and 2022, respectively. At December 31, 2023, the aggregate intrinsic value of outstanding options and exercisable options was $4.9 million and $4.7 million, respectively.

The following table summarizes information about stock options outstanding and exercisable at December 31, 2023 under the Plan:

The weighted-average grant date fair value of options granted was $4.87 and $5.49 per share for the years ended December 31, 2023 and 2022, respectively. The Company recorded stock-based compensation expense of $24.6 million and $23.9 million for the years ended December 31, 2023 and 2022, respectively, related to stock options. As of December 31, 2023, the total unrecognized compensation expense related to unvested stock option awards was $36.4 million, which the Company expects to recognize over a weighted-average period of 2.03 years.

The fair value of each option was estimated on the date of grant using the weighted average assumptions in the table below:

Restricted Stock Awards and Units

The Company issues restricted stock awards (“RSA”) to employees that generally vest over afour-year period with 25% of awards vesting after 1 year and then monthly thereafter. Any unvested shares will be forfeited upon termination of services. The fair value of an RSA is equal to the fair market value price of the Company’s common stock on the date of grant. RSA expense is recorded on a straight-line basis over the vesting period.

The following table summarizes activity related to RSA stock-based payment awards:

The Company recorded stock-based compensation expense of $0.5 million and $0.8 million for the years ended December 31, 2023 and 2022, respectively, related to RSAs. As of December 31, 2023, the total unrecognized expense related to all RSAs was $0.1 million, which the Company expects to recognize over a weighted-average period of 0.24 years.

The Company issues restricted stock units (“RSU”) to employees that generally vest over afour-year period with 25% of awards vesting after 1 year and then quarterly thereafter. Any unvested shares will be forfeited upon termination of services.

The following table summarizes activity related to RSU stock-based payment awards:

The Company recorded stock-based compensation expense of $0.3 million and $0.2 million for the years ended December 31, 2023 and 2022, respectively, related to RSUs. At December 31, 2023 the total unrecognized expense related to the RSUs was $0.6 million, which the Company expects to recognize over 2.12 years.

Employee Stock Purchase Plan

The Company has an Employee Stock Purchase Plan (the “ESPP”), which as of December 31, 2023 had 1,619,292 shares of common stock reserved for future issuance. The Company issued 169,857 shares under the ESPP in 2023. The number of shares of the Company’s common stock that may be issued pursuant to rights granted under the ESPP shall automatically increase on January 1st of each year and continuing forten years beginning in 2021, in an amount equal toone percent of the total number of shares of all classes of the Company’s common stock outstanding on December 31st of the preceding calendar year, subject to the discretion of the board of directors or compensation committee to determine a lesser number of shares shall be added for such year. As such, on January 1, 2024,549,142 shares were added to the ESPP.

Under the ESPP, eligible employees can purchase the Company’s common stock through accumulated payroll deductions at such times as are established by the compensation committee. Eligible employees may purchase the Company’s common stock at 85%of the lower of the fair market value of the Company’s common stock on the first day of the offering periodor on the last day of the offering period. Eligible employees may contribute up to 15% of their eligible compensation. Under the ESPP, a participant may not accrue rights to purchase more than $25,000 worth of the Company’s common stock for each calendar year in which such right is outstanding.

The ESPP is considered compensatory under the FASB stock compensation rules. Accordingly, share-based compensation expense is determined based on the option’s grant-date fair value as estimated by applying the Black Scholes option-pricing model and is recognized over the withholding period. The Company recognized share-based compensation expense of $0.3 million for both years ended December 31, 2023 and 2022 related to the ESPP.

11. Income Taxes

The tax effects of temporary differences that gave rise to significant portions of the deferred tax assets and liabilities were as follows:

The deferred tax assets as of December 31, 2023 and 2022, includes capitalized research and development expenses of $39.9 million and $19.9 million, respectively. The Tax Cuts and Jobs Act passed in 2017 included a provision which requires taxpayers to capitalize and amortize U.S. based research development expenses over a period offive years and non-U.S. based research and development expenses over a period of 15 years effective for tax years beginning after December 31, 2021. In assessing the need for a valuation allowance, management must determine that there will be sufficient taxable income to allow for the realization of deferred tax assets. Based upon the historical and anticipated future losses, management has determined that the deferred tax assets do not meet the more likely than not threshold for realizability. Accordingly, a full valuation allowance has been recorded against the Company’s net deferred tax assets as of December 31, 2023 and December 31, 2022. The valuation allowance increased by $36.6 million and $35.7 million during the years ended December 31, 2023 and 2022, respectively.

A reconciliation of the federal income tax rate to the Company’s effective tax rate is as follows:

The following table summarizes carryforwards of federal and state net operating losses (“NOL”) and research tax credits:

The NOL carryforwards begin expiring in 2036 for federal and Delaware state income tax purposes, however; all federal, Delaware state, and Kansas state NOL carryforwards generated subsequent to January 1, 2018, are able to be carried forward indefinitely. The NOL carryforwards begin expiring in 2037 and 2042 for Tennessee and Massachusetts, respectively. As of December 31, 2023, the Company also had federal and Delaware research and development tax credit carryforwards of $20.5 million and $43 thousand, respectively, that will begin to expire in 2039 and 2031, respectively, unless previously utilized.

The NOL and tax credit carryforwards are subject to review and possible adjustment by the Internal Revenue Service and state tax authorities. NOL and tax credit carryforwards may become subject to an annual limitation in the event of certain cumulative changes in the ownership interest of significant stockholders over a three year period in excess of 50%, as defined under Sections 382 and 383 of the Internal Revenue Code, respectively, as well as similar state provisions. This could limit the amount of tax attributes that can be utilized annually to offset future taxable income or tax liabilities. The amount of the annual limitation is determined based on the value of the Company immediately prior to the ownership change. Subsequent ownership changes may further affect the limitation in future years. To date, the Company has not performed an analysis to determine whether or not ownership changes have occurred since inception. Delaware state NOLs may also be limited.

As of December 31, 2023, the Company hadno accrued interest or penalties related to uncertain tax positions andno amounts have been recognized in the Company’s statement of operations. Due to NOL and tax credit carry-forwards that remain unutilized, income tax returns for all tax years remain subject to examination by the taxing jurisdictions. The NOL carryforwards remain subject to review until utilized.