ABOS US Equity☆

Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations.

The following discussion and analysis of our financial condition and results of operations should be read in conjunction with our audited financial statements and related notes appearing elsewhere in this Annual Report on Form 10-K. Some of the information contained in this discussion and analysis or set forth elsewhere in this Annual Report on Form 10-K, including information with respect to our future results of operations or financial condition, business strategy and plans and objectives of management for future operations, includes forward-looking statements that involve risks and uncertainties and should be read together with the “Risk Factors” section of this Annual Report on Form 10-K for a discussion of important factors that could cause our actual results to differ materially from those described in or implied by these forward-looking statements contained in the following discussion and analysis.

Overview

We are a clinical-stage biopharmaceutical company developing a novel disease-modifying approach to target what we believe to be a key underlying cause of Alzheimer’s disease, or AD. Alzheimer’s disease is a progressive neurodegenerative disease of the brain that leads to loss of memory and cognitive functions and ultimately results in death. Our scientific founders pioneered research on soluble amyloid-beta oligomers, or AßOs, which are globular assemblies of the amyloid-beta, or Aß, peptide that are distinct from Aß monomers and amyloid plaques. Based on decades of research and supporting evidence, AßOs have gained increasing scientific acceptance as a primary toxin involved in the initiation and propagation of AD pathology. We are currently focused on advancing a targeted immunotherapy drug candidate, sabirnetug, in clinical development following Phase 1 results in “early AD” patients (patients with mild cognitive impairment or mild dementia due to Alzheimer’s pathology) that were reported in July 2023. Sabirnetug is a recombinant humanized IgG2 mAb that was designed to selectively target AßOs, has demonstrated functional and protective effects in in vitro assays, and has demonstrated in vivo safety and pharmacologic activity in multiple animal species, including transgenic mouse models for AD.

In July 2023, we announced topline results from our Phase 1 clinical trial of sabirnetug, called INTERCEPT-AD, which demonstrated that sabirnetug met the primary and secondary objectives of this study in 62 participants with early AD. We expect to initiate a Phase 2 clinical trial of sabirnetug, called ALTITUDE-AD, in the first half of 2024. ALTITUDE-AD is a randomized, double-blind, placebo-controlled, three arm study designed to evaluate the clinical efficacy, safety and tolerability of sabirnetug, with up to 180 participants per arm for a total of up to 540 participants with mild cognitive impairment or mild dementia due to AD. We intend to use the Integrated Alzheimer’s Disease Rating Scale, or iADRS, at 18 months as the primary outcome measure. Our planned doses for ALTITUDE-AD are 35 mg/kg and 50 mg/kg both dosed every four weeks, or Q4W. These dose levels and frequency were selected based on extensive pharmacokinetic, or PK, and pharmacodynamic, or PD, modeling of our Phase 1 data. Based on regulatory feedback from the European Medicines Agency, or EMA, and to enhance the probability that the EMA will consider our Phase 2 study a registration-eligible study for sabirnetug, we anticipate amending the ALTITUDE-AD protocol later this year to change the current Phase 2/3 study to a Phase 2 standalone study. If this happens, any interim analysis may then lead to an initiation of a confirmatory Phase 3 study.

We were incorporated in 1996 and were party to an exclusive license and research collaboration with Merck in 2003. Although we acquired the exclusive rights to sabirnetug from Merck in 2011 following Merck’s strategic decision to focus its AD development efforts on a different product candidate, we did not recommence meaningful operations until we completed our first institutional fundraising in 2018. Since 2018, we have devoted substantially all of our efforts to organizing and staffing our company, business planning, raising capital, conducting discovery, research and development activities, and providing general and administrative support for these operations. We do not have any products approved for sale and have not generated any revenue from product sales. We have funded our operations primarily through the sale of our convertible preferred stock and common stock, the issuance of notes, entry into a term loan facility, grant revenue and during our collaboration with Merck, certain payments received under our collaboration agreement.

On July 21, 2023, we issued 16,774,193 shares of our common stock in an underwritten public offering, or the Offering, at a price to the public of $7.75 per share. The net proceeds from the offering, after underwriting discounts and commissions and other offering expenses, were $121.9 million.

In November 2023, we entered into a loan and security agreement, or the Loan Agreement, with K2 HealthVentures LLC, or, together with its affiliates, K2HV. The Loan Agreement provides us with a term loan facility in the aggregate principal amount of up to $50.0 million, of which we have borrowed $30.0 million in the first tranche and which was funded upon closing. The remaining $20.0 million is available for borrowing upon our request, subject to review by the lenders of certain information from us and discretionary approval by the lenders. The term loan facility matures on November 1, 2027 and can be extended to November 1, 2028, subject to our achievement of certain financing milestones. In accordance with

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the Loan Agreement, we issued to K2HV a warrant to purchase up to 730,769 shares of our common stock at an exercise price of $1.95 per share.

In January 2024, we issued 2,068,246 shares of our common stock under our at-the-market offering program, or the ATM, for net proceeds of $7.9 million, or $3.84 per share.

We have incurred net losses and negative cash flows from operations since our inception. Our net losses were $52.4 million and $42.9 million for the years ended December 31, 2023 and 2022, respectively. Approximately $42.3 million, or 81%, of the net loss for the year ended December 31, 2023 was due to research and development spending. As of December 31, 2023, we had an accumulated deficit of $222.8 million. Our net losses and cash flows from operations may fluctuate significantly from quarter-to-quarter and year-to-year, depending on the timing of nonclinical studies, clinical trials and our expenditures on other research and development activities. Our net losses and cash flows from operations may fluctuate significantly from quarter-to-quarter and year-to-year, depending on the timing of nonclinical studies, clinical trials and our expenditures on other research and development activities. We expect our expenses and operating losses will increase substantially for the foreseeable future as we advance sabirnetug in clinical trials, seek to expand our product candidate portfolio through developing additional product candidates, grow our clinical, regulatory and quality capabilities, and incur additional costs associated with operating as a public company. It is likely that we will seek third-party collaborators for the future commercialization of sabirnetug or any other product candidate that is approved for marketing. Should we seek to commercialize our products at our own expense, we would incur significant additional expenses for marketing, sales, manufacturing and distribution. We will not generate revenue from product sales unless and until we successfully complete clinical development and obtain regulatory approval for our product candidates.

As a result, we will need substantial additional funding to support our continuing operations and pursue our growth strategy. Until we can generate significant revenue from product sales, if ever, we expect to finance our operations through a combination of public or private equity offerings and debt financings or other sources, such as potential collaboration agreements, strategic alliances and licensing arrangements. We may be unable to raise additional funds or enter into such other agreements or arrangements when needed on acceptable terms, or at all. In addition, global economic conditions may impact our ability to raise additional funds, and we may be impacted by disruptions to, and volatility in, the credit and financial markets in the U.S. and worldwide, rising inflation and supply disruptions, the ongoing conflict between Russia and Ukraine and Israel and Hamas and related sanctions, and otherwise. If these conditions persist and deepen, we could experience an inability to access additional capital, or our liquidity could otherwise be impacted. If we are unable to raise capital when needed or on attractive terms, we would be forced to delay, reduce or eliminate our research and development programs and/or future commercialization efforts. Our failure to raise capital or enter into such agreements as, and when needed, could have a material adverse effect on our business, results of operations and financial condition.

As of December 31, 2023, we had cash and cash equivalents and marketable securities of $306.1 million; included in this amount is the first tranche of $30.0 million that we received under our Loan Agreement, which was received on November 10, 2023. Based on our current operating plan, we expect that our existing cash and cash equivalents and marketable securities, will be sufficient to enable us to fund our operating expenses and capital expenditure requirements into the first half of 2027. We have based this estimate on assumptions that may prove to be wrong, and we could exhaust our available capital resources sooner than we expect, including based on our decision to initiate other clinical trials or programs. See “Liquidity and Capital Resources.”

Components of Results of Operations

Operating Expenses

Our operating expenses consist of research and development expenses and general and administrative expenses.

Research and Development Expenses

Research and development costs primarily consist of direct costs associated with consultants and materials, biologic storage, third party, contract research organizations, or CRO, costs and contract manufacturing organization, or CMO, expenses, salaries and other personnel-related expenses. Research and development costs are expensed as incurred. More specifically, these costs include:

•costs of funding research performed by third parties that conduct research and development and nonclinical and clinical activities on our behalf;

•costs of manufacturing drug supply and drug product;

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•costs of conducting nonclinical studies and clinical trials of our product candidates;

•consulting and professional fees related to research and development activities, including stock-based compensation to non-employees;

•costs related to compliance with clinical regulatory requirements; and

•employee-related expenses, including salaries, benefits and stock-based compensation expense for our research and development personnel.

As we currently only have one product candidate, sabirnetug, in development, we do not separately track expenses by program. Further, we have historically relied primarily on consultants for research and development activities; our internal research and development personnel costs currently represent approximately 22% of our total research and development expenses. Our research and development expenses increased substantially since initiating the clinical trial program for sabirnetug in 2021. We expect that our research and development expenses will continue to increase, substantially in connection with our continued clinical development activities for sabirnetug.

General and Administrative Expenses

General and administrative expenses consist primarily of employee-related expenses, including stock-based compensation costs, as well as business insurance, management and business consultants and other related costs. General and administrative expenses also include professional fees for legal, consulting, accounting, auditing, tax and patent services, investor and public relations, board of directors’ expenses, information technology, franchise taxes, rent, travel expenses and subscriptions.

We expect that our general and administrative expenses will increase as our organization and headcount needed in the future grows to support continued research and development activities and potential commercialization of our product candidates. These increases will likely include increased costs related to the hiring of additional personnel and fees to outside consultants, attorneys and accountants, among other expenses. Additionally, we expect to continue to incur significant expenses associated with being a public company, including costs of additional personnel, accounting, audit, legal, regulatory and tax-related services associated with maintaining compliance with exchange listing and Securities and Exchange Commission, or SEC, requirements, director and officer insurance costs, and investor and public relations costs.

Other Income (Expense)

Other income (expense) primarily includes interest income, interest expense, change in fair value of embedded derivatives and other expense, net. The interest income earned, as well as amortization and accretion of premiums and discounts, related to our investments in marketable securities are recorded in interest income. Interest expense includes interest due under the Loan Agreement, as well as the amortization of the related debt discount. The change in fair value of embedded derivatives relates to the embedded derivatives that were bifurcated from the term loan, borrowed under the Loan Agreement, and accounted for as a derivative at fair value and is remeasured at each reporting period for the term of the loan. Other expense, net generally consists of fees incurred on our investments in marketable securities partially offset by sublease income.

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Results of Operations

Comparison of the Years Ended December 31, 2023 and 2022

The following table summarizes our results of operations for the years ended December 31, 2023 and 2022 (in thousands):

Year Ended December 31, Change

Costs and operating expenses

Other income (expense)

Change in fair value of embedded derivatives (1,360) — (1,360) 100 %

Other expense, net (83) (11) (72) *

*Not meaningful

Research and Development Expenses

Research and development expenses were $42.3 million and $32.4 million for the years ended December 31, 2023 and 2022, respectively. The $9.9 million increase was primarily due to increases in expenses of $4.0 million for personnel-related expenses, including an increase of $1.0 million for non-cash stock-based compensation expenses, $3.2 million for services provided by contractors and consultants, $1.0 million for license agreements, $0.8 million for other clinical trial expenses, $0.6 million for storage, shipping and packaging, $0.3 million for materials, $0.3 million for CRO costs and $0.1 million for travel expenses; all of which was primarily related to increases in costs associated with the planning phase of our anticipated Phase 2 clinical trial and decreases associated with the conclusion of our Phase 1 clinical trial, which was initiated in 2021 with topline results announced in July 2023. All of the above increases were partially offset by a $0.4 million decrease in assay development costs.

General and Administrative Expenses

General and administrative expenses were $18.8 million and $12.9 million for the years ended December 31, 2023 and 2022, respectively. The $5.9 million increase was primarily due to increases of $4.7 million for personnel costs, including an increase of $2.1 million for non-cash stock-based compensation expenses, $0.8 million for consulting expenses, $0.6 million for legal/patent expenses, $0.2 million for audit-related expenses, and $0.2 million for software licenses and computer equipment, partially offset by a reduction of $0.7 million in corporate insurance expenses.

Other Income (Expense)

Other income increased $6.4 million to $8.8 million for the year ended December 31, 2023 from $2.4 million for the year ended December 31, 2022. The increase was primarily attributable to an $8.4 million increase in interest income on our portfolio of marketable securities due to both higher interest rates and increased investment in marketable securities following the Offering; partially offset by a $1.4 million increase in change in the fair value of embedded derivatives due to the increase in fair value of the embedded derivatives that are bifurcated from the term loan under the Loan Agreement, from the time of the closing of the Loan Agreement until December 31, 2023 and an increase in interest expense of $0.6 million related to our Loan Agreement funded in November 2023.

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Liquidity and Capital Resources

We have incurred net losses since inception. We have not generated any revenue from product sales or any other sources other than grant revenue and have incurred significant operating losses. We have not yet commercialized any products and we do not expect to generate revenue from sales of any drug candidates for at least several years, if ever.

Our operations have been financed primarily by net proceeds from the sale and issuance of our common stock and convertible preferred stock, net proceeds from our IPO and Offering, the issuance of notes, grant revenue and, during our collaboration with Merck & Co. Inc. which was in place from 2003 to 2011, certain payments received under our collaboration agreement.

On July 21, 2023, we issued 16,774,193 shares of our common stock, $0.0001 par value per share, or Common Stock, in the Offering at a price of $7.75 per share. The aggregate net proceeds from the Offering, after underwriting discounts and commissions and other offering expenses, were $121.9 million.

On July 1, 2022, we filed a shelf registration statement on Form S-3, or the Registration Statement. Pursuant to the Registration Statement, we may offer and sell securities having an aggregate public offering price of up to $200.0 million. In connection with the filing of the Registration Statement, we also entered into a sales agreement, or the Sales Agreement, with BofA Securities, Inc. and Stifel, Nicolaus & Company, Incorporated, as sales agents, pursuant to which we may issue and sell shares of our Common Stock for an aggregate offering price of up to $50.0 million under an at-the-market offering program, or ATM, which is included in the $200.0 million of securities that may be offered pursuant to the Registration Statement. On April 23, 2023, we entered into an amendment to the Sales Agreement, or, as amended, the Amended Sales Agreement, to add BTIG, LLC as a sales agent under the Amended Sales Agreement. Pursuant to the Amended Sales Agreement, we will pay the sales agents a commission rate of up to 3.0% of the gross proceeds from the sale of any shares of our Common Stock. We are not obligated to make any sales of shares of our Common Stock under the ATM. We did not sell any shares of our Common Stock under the ATM during the year ended December 31, 2023.

In January 2024, we issued 2,068,246 shares of Common Stock under the ATM for net proceeds of $7.9 million, or $3.84 per share.

On November 10, 2023, we received the first tranche of $30.0 million under the Loan Agreement. As of December 31, 2023, we had cash and cash equivalents and marketable securities totaling $306.1 million. Our available-for-sale marketable securities mature over the next two years. Based on our current operating plan, we expect that our existing cash and cash equivalents and marketable securities will be sufficient to enable us to fund our operating expenses and capital expenditure requirements into the first half of 2027. We have based this estimate on assumptions that may prove to be wrong, and we could exhaust our available capital resources sooner than we expect, including based on our decision to initiate other clinical trials or programs.

We enter into contracts in the normal course of business with CROs and CMOs for clinical trials, nonclinical research studies and testing, manufacturing and other services and products for operating purposes. These contracts do not contain any minimum purchase commitments and are generally cancellable by us after giving a certain amount notice. Payments due upon cancellation consist only of payments for services provided and expenses incurred up to the date of cancellation.

Cash Flows

The following table summarizes our sources and uses of cash (in thousands):

Year Ended December 31,

Net cash used in operating activities $ (43,064) $ (35,153)

Net cash provided by (used in) investing activities (171,671) 39,185

Net cash provided by financing activities 151,753 3,907

Net change in cash and cash equivalents $ (62,982) $ 7,939

Operating Activities

Net cash used in operating activities increased by $7.9 million to.$43.1 million for the year ended December 31, 2023 from $35.2 million for the year ended December 31, 2022. The $9.5 million increased net loss for the year ended December 31,

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2023, as adjusted for non-cash net expenses totaling $1.7 million, some of which included an increase in stock-based compensation of $3.1 million, a decrease in amortization and accretion on marketable securities of $3.6 million, an increase in change in fair value of embedded derivatives of $1.4 million and an increase in non-cash equipment lease costs of $0.7 million, was responsible for $7.8 million of the increase in cash used in operating activities as compared to the prior year. Working capital changes, including increases in cash used for prepaid expenses and other current assets of $2.1 million, related primarily to advances for research and development, accrued clinical trial expenses of $0.9 million and accounts payable of $0.8 million, were partially offset by increases in cash provided by accrued expenses and other current liabilities of $3.6 million.

Investing Activities

Net cash used in investing activities increased by $210.9 million to $171.7 million for the year ended December 31, 2023 from cash provided by investing activities of $39.2 million for the year ended December 31, 2022, and was primarily due to an increase in purchases of marketable securities of $209.1 million and a decrease in maturities of marketable securities of $1.9 million.

Financing Activities

Net cash provided by financing activities increased by $147.9 million to $151.8 million for the year ended December 31, 2023 from $3.9 million for the year ended December 31, 2022. The increase was primarily due to $121.9 million of net proceeds from the Offering, and $29.5 million of net proceeds under the Loan Agreement for the year ended December 31, 2023, as compared to $3.8 million of net proceeds from the issuance of Common Stock under our ATM for the year ended December 31, 2022.

Funding Requirements

We expect our expenses to increase in connection with our ongoing activities, particularly as we continue our research and development, conduct clinical trials, and seek marketing approval for our current and any of our future product candidates. Furthermore, we expect to incur additional costs associated with operating as a public company. It is likely that we will seek third-party collaborators for the future commercialization of sabirnetug or any other product candidate that is approved for marketing. Should we seek to commercialize our products at our own expense, we would incur significant additional expenses for marketing, sales, manufacturing and distribution, which costs we may seek to offset through entry into collaboration agreements with third parties. As a result, we expect that we will need to obtain substantial additional funding in connection with our future operations. If we are unable to raise capital when needed or on acceptable terms, we could be forced to delay, reduce or eliminate our research and development programs or future commercialization efforts.

Based on our current operating plan, we believe that our existing cash and cash equivalents and marketable securities will be sufficient to enable us to fund our operating expenses and capital expenditure requirements into the first half of 2027. We have based this estimate on assumptions that may prove to be wrong, and we could exhaust our available capital resources sooner than we expect, including based on our decision to initiate other clinical trials or programs. In addition, changing circumstances may cause us to increase our spending significantly faster than we currently anticipate, and we may need to spend more money than currently expected because of circumstances beyond our control. We may need to raise additional funds sooner than anticipated if we choose to expand more rapidly than we presently anticipate.

The amount and timing of our future funding requirements will depend on many factors, some of which are outside of our control, including but not limited to:

•the progress, costs, timing and results of ALTITUDE-AD and other potential clinical trials of sabirnetug, including for potential additional indications that we may pursue beyond AD;

•the requirements of the U.S. Food and Drug Administration, or the FDA, and European Medicines Agency, or EMA, and comparable foreign regulatory authorities, for clinical trials and nonclinical studies and other work, for review and approval of sabirnetug for AD;

•the outcome, costs and timing of seeking and obtaining FDA, EMA and any other regulatory approvals;

•the number and characteristics of product candidates that we pursue;

•our ability to obtain sufficient quantities of our product candidates from our third-party manufacturers;

•our need to expand our research and development activities;

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•the costs associated with securing and establishing commercialization capabilities if we were to elect to commercialize one or more products on our own;

•the economics and other terms, timing of and success of any collaboration, licensing or other arrangements into which we may enter for the commercialization of our products;

•the costs and other terms, timing and success, of acquiring, in-licensing or investing in businesses, product candidates and technologies;

•our ability to maintain, expand and defend the scope of our intellectual property portfolio, including the amount and timing of any payments we may be required to make, or that we may receive, in connection with the licensing, filing, prosecution, defense and enforcement of any patents or other intellectual property rights;

•our need and ability to retain management and hire scientific and clinical personnel;

•the effect of competing drugs and product candidates and other market developments; and

•our need to implement additional internal systems and infrastructure, including financial and reporting systems.

Additional funding may not be available to us on acceptable terms or at all. Any such funding may result in dilution to stockholders, imposition of debt covenants and repayment obligations or other restrictions that may affect our business. We also could be required to seek funds through arrangements with collaborative partners or otherwise that may require us to relinquish rights to some of our technologies or product candidates or otherwise agree to terms unfavorable to us. Any funds we raise may not be sufficient to enable us to continue to implement our long-term business strategy. Further, our ability to raise additional capital may be adversely impacted by potential worsening global economic conditions and the recent disruptions to and volatility in the credit and financial markets in the United States and worldwide. Additionally, escalation in interest rates, in conjunction with banking failures, may lead to financial institutions being more prudent with capital deployment and tightening lending. If we are unable to raise sufficient additional capital on a timely basis, we could be forced to curtail our planned operations and the pursuit of our business strategy, which would have a material adverse effect on the value of our common stock.

Critical Accounting Policies, Significant Judgments and Use of Estimates

The preparation of financial statements in conformity with U.S. generally accepted accounting principles, or U.S. GAAP, requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of expenses incurred during the reporting periods. Our estimates and assumptions are based on our historical experience and on various other factors that we believe are reasonable under the circumstances, the results of which form the basis for making judgments about the carrying value of assets and liabilities that are not readily apparent from other sources.

Actual results may differ from these estimates under different assumptions or conditions. We believe that the accounting policies discussed below are critical to understanding our historical and future performance, as these policies relate to the more significant areas involving management’s judgments and estimates.

While our significant accounting policies are described in the notes to our financial statements included elsewhere in this Annual Report for Form 10-K, we believe that the following critical accounting policies are most important to understanding and evaluating our reported financial results.

Stock-Based Compensation Expense

We recognize stock-based compensation expense for all stock-based awards. Stock-based compensation costs are estimated at the grant date based on the fair value of the equity and recognized as expense, net of actual forfeitures when they occur, on a straight-line basis over the requisite service period.

We calculate the fair value of options using the Black-Scholes option-pricing model, which requires the use of various highly subjective assumptions as follows:

•Fair Value of Common Stock—We use the closing price of our publicly traded Common Stock.

•Expected Term—We have opted to use the “simplified method” for estimating the expected term of options, whereby the expected term equals the arithmetic average of the mid-point between the vesting date and the end of contractual term of the option (generally ten years).

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•Expected Volatility—Due to our limited operating history and a lack of sufficient company-specific historical and implied volatility data, we have based our estimate of expected volatility on a blended volatility of the volatility of our stock price following our IPO and the historical volatility of a group of industry peers that are publicly traded. We will continue to utilize this blended approach to estimate volatility until a sufficient amount of historical information regarding the volatility of our own stock is available.

•Risk-Free Interest Rate—The risk-free rate assumption is based on the U.S. Treasury yield in effect at the time of the grant with maturities consistent with the expected term of our options.

•Expected Dividend Yield—We have not issued any dividends in our history and do not expect to pay dividends on our common stock over the life of the options and therefore have estimated the dividend yield to be zero.

We will continue to use judgment in evaluating the expected volatility, expected terms and interest rates utilized for our stock-based compensation expense calculations on a prospective basis.

Accrued Research and Development Expenses

As part of the process of preparing our financial statements, we are required to estimate our accrued expenses as of each balance sheet date. This process involves reviewing open contracts and purchase orders, identifying services that have been performed on our behalf and estimating the level of service performed and the associated cost incurred for the service when we have not yet been invoiced or otherwise notified of the actual cost. We make estimates of our accrued expenses as of each balance sheet date based on facts and circumstances known to us at that time. We periodically confirm the accuracy of our estimates with the service providers and make adjustments if necessary. The significant estimates in our accrued research and development expenses include the costs incurred for services performed by our vendors in connection with research and development activities for which we have not yet been invoiced. Since our inception, we have not experienced any material differences between accrued or prepaid costs and actual costs.

We base our expenses related to research and development activities on our estimates of the services received and efforts expended pursuant to quotes and contracts with vendors that conduct research and development on our behalf. The financial terms of these agreements are subject to negotiation, vary from contract to contract and may result in uneven payment flows. There may be instances in which payments made to our vendors will exceed the level of services provided and result in a prepayment of the research and development expense. In accruing service fees, we estimate the time period over which services will be performed and the level of effort to be expended in each period. If the actual timing of the performance of services or the level of effort varies from our estimate, we adjust the accrual or prepaid expense accordingly. Advance payments for goods and services that will be used in future research and development activities are expensed when the activity has been performed or when the goods have been received rather than when the payment is made.

Clinical trial costs are a significant component of accrued research and development expenses and include costs associated with third-party contractors. We accrue and expense costs for clinical trial activities performed by third parties based upon the work completed to date for each clinical trial in accordance with established agreements. Management determines costs through discussions with internal clinical stakeholders and outside service providers as to the progress or stage of completion of clinical trials or services and the contracted fee to be paid for such services. In the event advance payments are made to an outside service provider, the payments are recorded within prepaid expenses and other current assets in the balance sheetand subsequently recognized as research and development expense in the statement of operationsand comprehensive losswhen the associated services have been performed. As actual costs become known, we adjust our estimates, liabilities and assets. Inputs used in the determination of estimates discussed above may vary from actual, which will result in adjustments to research and development expense in future periods.

Embedded Derivatives

We evaluate embedded derivatives within convertible debt to determine whether the embedded derivatives should be bifurcated from the host instrument and accounted for as a derivative at fair value that will be remeasured at each reporting period for the term of the loan with changes in fair value recorded in the statements of operations and comprehensive loss. We initially assess the probability of the occurrence of trigger events for bifurcated embedded derivatives in determining fair value. The probability is reassessed at each reporting period during the term of a loan.

We calculate the fair value of embedded derivatives using the Monte Carlo option-pricing model, which requires the use of various highly subjective assumptions, including the expected term, expected volatility, risk-free interest rate and expected

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dividend yield. Our selection of the expected volatility, risk-free interest rate and expected dividend yield are discussed above under Stock-Based Compensation Expense.

Emerging Growth Company and Smaller Reporting Company Status

In April 2012, the Jumpstart Our Business Startups Act of 2012, or JOBS Act, was enacted. Section 107 of the JOBS Act provides that an “emerging growth company” can take advantage of the extended transition period provided in Section 7(a)(2)(B) of the Securities Act of 1933, as amended, for complying with new or revised accounting standards. Thus, an emerging growth company can delay the adoption of certain accounting standards until those standards would otherwise apply to private companies. We elected to use the extended transition period for complying with new or revised accounting standards, which delays the adoption of these accounting standards until they would apply to private companies.

In addition, as an emerging growth company, we may take advantage of specified reduced disclosure and other requirements that are otherwise applicable generally to public companies. These provisions include:

•an exception from compliance with the auditor attestation requirements of Section 404 of the Sarbanes-Oxley Act of 2002, as amended;

•reduced disclosure about our executive compensation arrangements in our periodic reports, proxy statements and registration statements;

•exemptions from the requirements of holding non-binding advisory votes on executive compensation or golden parachute arrangements; and

•an exemption from compliance with the requirements of the Public Company Accounting Oversight Board regarding the communication of critical audit matters in the auditor’s report on financial statements.

We may take advantage of these provisions until we no longer qualify as an emerging growth company. We will cease to qualify as an emerging growth company on the date that is the earliest of: (i) December 31, 2026, (ii) the last day of the fiscal year in which we have more than $1.235 billion in total annual gross revenues, (iii) the date on which we are deemed to be a “large accelerated filer” under the rules of the SEC, which means the market value of our common stock that is held by non-affiliates exceeds $700 million as of the prior June 30th, or (iv) the date on which we have issued more than $1.0 billion of non-convertible debt over the prior three-year period. We may choose to take advantage of some but not all of these reduced reporting burdens. We have taken advantage of certain reduced reporting requirements in this Annual Report on Form 10-K and our other filings with the SEC. Accordingly, the information contained herein may be different than you might obtain from other public companies in which you hold equity interests.

We are also a “smaller reporting company,” meaning that the market value of our shares held by non-affiliates is less than $700 million and our annual revenue was less than $100 million during the most recently completed fiscal year. We may continue to be a smaller reporting company if either (i) the market value of our shares held by non-affiliates is less than $250 million or (ii) our annual revenue was less than $100 million during the most recently completed fiscal year and the market value of our shares held by non-affiliates is less than $700 million. If we are a smaller reporting company at the time we cease to be an emerging growth company, we may continue to rely on exemptions from certain disclosure requirements that are available to smaller reporting companies. Specifically, as a smaller reporting company, we may choose to present only the two most recent fiscal years of audited financial statements in our Annual Report on Form 10-K and, similar to emerging growth companies, smaller reporting companies have reduced disclosure obligations regarding executive compensation.

Item 7A. Quantitative and Qualitative Disclosures About Market Risk.

Not applicable to a smaller reporting company.

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Item 8. Financial Statements and Supplementary Data.

ACUMEN PHARMACEUTICALS, INC.

INDEX TO FINANCIAL STATEMENTS

Page

Report of Independent Registered Public Accounting Firm (PCAOB ID: 42) 90

Statements of Cash Flows for the years ended December 31, 2023 and 2022 94

Notes to Financial Statements 95

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Report of Independent Registered Public Accounting Firm

To the Shareholders and the Board of Directors of Acumen Pharmaceuticals, Inc.

Opinion on the Financial Statements

We have audited the accompanying balance sheets of Acumen Pharmaceuticals, Inc. (the Company) as of December 31, 2023 and 2022, the related statements of operations and comprehensive loss, changes in stockholders’ equity and cash flows for each of the two years in the period ended December 31, 2023, and the related notes(collectively referred to as the “financial statements”). In our opinion, the financial statements present fairly, in all material respects, the financial position of the Company at December 31, 2023 and 2022, and the results of its operations and its cash flows for each of the two years in the period ended December 31, 2023, in conformity with U.S. generally accepted accounting principles.

Basis for Opinion

These financial statements are the responsibility of the Company's management. Our responsibility is to express an opinion on the Company’s financial statements based on our audits. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) (PCAOB) and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud. The Company is not required to have, nor were we engaged to perform, an audit of its internal control over financial reporting. As part of our audits we are required to obtain an understanding of internal control over financial reporting but not for the purpose of expressing an opinion on the effectiveness of the Company's internal control over financial reporting. Accordingly, we express no such opinion.

Our audits included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements. We believe that our audits provide a reasonable basis for our opinion.

/s/ Ernst & Young LLP

We have served as the Company’s auditors since 2021.

Tysons, Virginia

March 26, 2024

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ACUMEN PHARMACEUTICALS, INC.

BALANCE SHEETS

(in thousands, except share and per share data)

December 31,

ASSETS

Current assets

Prepaid expenses and other current assets 3,093 2,724

Restricted cash 233 —

Property and equipment, net 122 165

LIABILITIES AND STOCKHOLDERS’ EQUITY

Current liabilities

Accrued clinical trial expenses 4,387 2,717

Accrued expenses and other current liabilities 6,339 3,350

Finance lease liability, short-term 756 —

Operating lease liability, short-term 110 105

Operating lease liability, long-term 284 —

Commitments and contingencies (Note 11)

Stockholders’ equity

Accumulated other comprehensive income (loss) 312 (751)

Total liabilities and stockholders’ equity $ 310,125 $ 196,587

The accompanying notes are an integral part of these financial statements.

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ACUMEN PHARMACEUTICALS, INC.

STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS

(in thousands, except share and per share data)

Year Ended December 31,

Operating expenses

Other income (expense)

Change in fair value of embedded derivatives (1,360) —

Interest expense (581) —

Other expense, net (83) (11)

Other comprehensive gain (loss)

Unrealized gain (loss) on marketable securities 1,063 (520)

Net loss per common share, basic and diluted $ (1.08) $ (1.06)

The accompanying notes are an integral part of these financial statements.

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ACUMEN PHARMACEUTICALS, INC.

STATEMENTS OF CHANGES IN STOCKHOLDERS’ EQUITY

(in thousands, except share data)

Shares Amount

Unrealized loss on marketable securities — — — — (520) (520)

Cashless exercise of stock options 4,746 — — — — —

Stock-based compensation — — 3,061 — — 3,061

Issuance of warrant with Term Loan — — 1,132 — — 1,132

Unrealized gain on marketable securities — — — — 1,063 1,063

Stock-based compensation — — 6,145 — — 6,145

The accompanying notes are an integral part of these financial statements.

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ACUMEN PHARMACEUTICALS, INC.

STATEMENTS OF CASH FLOWS

(in thousands)

Year Ended December 31,

Cash flows from operating activities

Adjustments to reconcile net loss to net cash used in operating activities:

Stock-based compensation expense 6,145 3,061

Change in fair value of embedded derivatives 1,360 —

Amortization of right-of-use asset 123 137

Non-cash research and development expense 739 —

Realized gain on marketable securities (11) —

Non-cash interest expense 145 —

Changes in operating assets and liabilities:

Prepaid expenses and other current assets (369) 1,700

Accrued clinical trial expenses 1,670 2,570

Accrued expenses and other current liabilities 2,989 (562)

Finance lease liability 17 —

Operating lease liability (110) (137)

Net cash used in operating activities (43,064) (35,153)

Cash flows from investing activities

Proceeds from maturities and sales of marketable securities 78,981 80,860

Proceeds from sale of property and equipment 3 —

Purchases of property and equipment (21) (161)

Net cash provided by (used in) investing activities (171,671) 39,185

Cash flows from financing activities

Proceeds from issuance of common stock, net of issuance costs 121,904 3,792

Proceeds from Term Loan 30,000 —

Payments for financing costs (476) —

Proceeds from exercise of stock options 325 115

Net cash provided by financing activities 151,753 3,907

Net change in cash and cash equivalents and restricted cash (62,982) 7,939

Supplemental disclosure of cash flow information

Cash paid for income taxes $ — $ —

Cash paid for interest $ 169 $ —

Supplemental disclosure of noncash financing activities

Right-of-use assets obtained in exchange for finance lease liabilities $ 739 $ —

Issuance of warrant with Term Loan $ 1,132 $ —

The accompanying notes are an integral part of these financial statements.

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ACUMEN PHARMACEUTICALS, INC.

NOTES TO FINANCIAL STATEMENTS

NOTE 1. DESCRIPTION OF ORGANIZATION AND BUSINESS OPERATIONS

Acumen Pharmaceuticals, Inc. (“Acumen” or the “Company”) was incorporated in 1996 in the state of Delaware. Acumen is a clinical-stage biopharmaceutical company developing a novel disease-modifying approach to target what the Company believes to be a key underlying cause of Alzheimer’s disease (“AD”). Alzheimer’s disease is a progressive neurodegenerative disease of the brain that leads to loss of memory and cognitive functions and ultimately results in death. The Company’s scientific founders pioneered research on soluble amyloid-beta oligomers (“AßOs”), which are globular assemblies of the amyloid-beta (“Aß”) peptide that are distinct from Aß monomers and amyloid plaques. Based on decades of research and supporting evidence, AßOs have gained increasing scientific acceptance as a primary toxin involved in the initiation and propagation of AD pathology. The Company is currently focused on advancing a targeted immunotherapy drug candidate, sabirnetug, in clinical development following Phase 1 results in “early AD” patients (patients with mild cognitive impairment or mild dementia due to Alzheimer’s pathology) that were reported in July 2023. Sabirnetug is a recombinant humanized immunoglobulin gamma 2 (“IgG2”) monoclonal antibody (“mAb”) that was designed to selectively target AßOs, has demonstrated functional and protective effects in in vitro assays, and has demonstrated in vivo safety and pharmacologic activity in multiple animal species, including transgenic mouse models for AD.

The Company is subject to the uncertainty of whether its intellectual property will develop into successful commercial products.

Public Offering

On July 21, 2023, the Company issued 16,774,193 shares of its common stock, $0.0001 par value per share (“Common Stock”), in a public offering (the “Offering”) at a price of $7.75 per share. The aggregate net proceeds from the Offering, after underwriting discounts and commissions and other offering expenses, were $121.9 million. See additional discussion in Note 8. Stockholders’ Equity.

Liquidity and Capital Resources

The Company has incurred operating losses since inception and expects to continue to incur significant operating losses for the foreseeable future and may never become profitable. As of December 31, 2023 and 2022, the Company had an accumulated deficit of $222.8 million and $170.4 million, respectively, and working capital of $233.6 million and $172.5 million, respectively. During 2023, the Company received cash from the Offering and borrowings with net proceeds of $29.5 million under a term loan facility (see Note 6. Debt). Management believes that the Company has sufficient cash to continue operating activities for beyond 12 months from issuance of these financial statements.

Future capital requirements will depend upon many factors, including the timing and extent of spending on research and development and market acceptance of the Company’s products, if approved for commercial sale. The Company expects that it will need to obtain additional financing to complete clinical trials and launch and commercialize any product candidates for which it receives regulatory approval. Until such time, if ever, as the Company can generate revenue sufficient to achieve profitability, the Company expects to finance its operations through a combination of equity offerings, debt financings, collaborations, strategic alliances and licensing arrangements. There can be no assurance that any such financing will be available on terms acceptable to the Company, or at all. To the extent that the Company raises additional capital through the sale of equity or convertible debt securities, the ownership interest of its stockholders will be diluted, and the terms of these securities may include liquidation of other preferences that adversely affect the rights of common stockholders. Debt financing and preferred equity financing, if available, may involve agreements that include covenants limiting or restricting the Company’s ability to take specific actions, such as incurring additional debt, making acquisitions or capital expenditures or declaring dividends. If the Company is unable to maintain sufficient financial resources, its business, financial condition and results of operations will be materially and adversely affected. The Company may be required to delay, limit, reduce or terminate its product discovery and development activities or future commercialization efforts.

The Company completed a Phase 1 clinical trial of sabirnetug in the second quarter of 2023, which the Company named “INTERCEPT-AD.” This trial enrolled 65 patients with “early AD” and 62 participants received at least one dose of study drug. INTERCEPT-AD was a U.S.-based, multi-center, randomized, double-blind, placebo-controlled clinical trial with overlapping single ascending dose and multiple ascending dose cohorts evaluating patients with early AD. In July 2023, the

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Company announced topline results from INTERCEPT-AD, which demonstrated that sabirnetug met the primary and secondary objectives of this study in 62 participants with early AD. The Company expects to initiate a Phase 2 clinical trial of sabirnetug called “ALTITUDE-AD” in the first half of 2024.

NOTE 2. BASIS OF PRESENTATION, SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES AND RECENT ACCOUNTING PRONOUNCEMENTS

Basis of Presentation

The accompanying financial statements of the Company have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) and pursuant to the rules and regulations of the U.S. Securities and Exchange Commission (“SEC”). In the opinion of management, all adjustments (consisting of normal recurring adjustments) have been made that are necessary to present fairly the Company’s financial position, and the results of its operations and its cash flows.

Emerging Growth Company

From time to time, new accounting pronouncements are issued by the Financial Accounting Standards Board (“FASB”) or other standard setting bodies and adopted by the Company as of the specified effective date. Unless otherwise discussed, the impact of recently issued standards that are not yet effective will not have a material impact on the Company’s financial statements upon adoption. Under the Jumpstart Our Business Startups Act of 2012, as amended, the Company meets the definition of an emerging growth company and has elected to use the extended transition period for complying with new or revised accounting standards, which delays the adoption of these accounting standards until they would apply to private companies.

Use of Estimates

The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements, as well as the reported amounts of expenses during the reporting periods. These estimates and assumptions are based on the Company’s historical experience, and on various other factors that management believes are reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities and the recording of expenses that are not readily apparent from other sources.

Actual results may differ from these estimates under different assumptions or conditions. To the extent there are material differences between the estimates and actual results, the Company’s future results of operations will be affected. The more significant estimates and assumptions by management include, among others: the valuation allowance of deferred tax assets resulting from net operating losses, the valuation of stock options, the valuation of the warrant to purchase Common Stock and the valuation of embedded derivatives within the Company’s debt, long-term.

Cash and Cash Equivalents and Restricted Cash

The Company considers all highly liquid investments with an original maturity of three months or less at the date of purchase to be cash equivalents. All of the Company’s cash equivalents have liquid markets and high credit ratings. The Company had $66.2 million and $129.1 million in cash equivalents as of December 31, 2023 and 2022, respectively.

Restricted cash primarily consists of deposited cash collateral for the Company’s credit card program.

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The following table provides a reconciliation of cash, cash equivalents and restricted cash from the balance sheets to the statements of cash flows (in thousands):

December 31,

Restricted cash 233 —

Total cash, cash equivalents and restricted cash $ 67,119 $ 130,101

Marketable Securities

The Company’s marketable securities portfolio consists primarily of investments in money market funds, asset-backed securities, U.S. treasury and agency securities and short-term highly liquid, high credit quality corporate debt securities. The Company considers its marketable securities to be available-for-sale. Available-for-sale securities are classified as cash equivalents, or as short-term or long-term marketable securities based on the maturity date at the time of purchase and their availability to meet current operating requirements. Available-for-sale securities that mature in three months or less from the date of purchase are classified as cash equivalents. Available-for-sale securities, excluding cash equivalents, that mature in one year or less are classified as short-term marketable securities and those that mature in more than one year are classified as long-term.

Securities that are classified as available-for-sale are measured at fair value; see “Fair Value of Financial Instruments” below. Any premium arising at purchase is amortized to the earliest call date and any discount arising at purchase is accreted to maturity. Amortization of premiums and accretion of discounts are recorded along with interest income on investments in interest income, net in the statements of operations and comprehensive loss. Unrealized gains and losses are excluded from earnings and are reported as a component of other comprehensive income. The cost of investments sold will be calculated using the specific-identification method.

For securities available-for-sale, Accounting Standards Update 2016-13, Financial Instruments-Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments eliminates the concept of other-than-temporary impairment and instead requires entities to determine if impairment is related to credit loss or non-credit loss. In making the assessment of whether a loss is from credit or other factors, management considers the extent to which fair value is less than amortized cost, any changes to the rating of the security by a rating agency and adverse conditions related to the security, among other factors. If this assessment indicates that a credit loss exists, the present value of cash flows expected to be collected from the security are compared to the amortized cost basis of the security. If the present value of cash flows is less than the amortized cost basis, a credit loss exists and an allowance is created, limited by the amount that the fair value is less than the amortized cost basis. Subsequent activity related to the credit loss component in the form of write-offs or recoveries is recognized as part of the allowance for credit losses on securities available-for-sale. The Company has made the accounting policy election to exclude accrued interest receivable on securities from the estimate of credit losses and will record a credit loss expense for accrued interest receivable in the period when a credit loss is recorded for the related securities. Management determined that the Company did not require an allowance for credit losses for available-for-sale securities as of December 31, 2023 or 2022, as only a small number of investments had a present value of cash flows expected to be collected in excess of the amortized cost, and the aggregate amount of this credit loss was immaterial. The Company did not have any related write-offs or recoveries for the years ended December 31, 2023 and 2022.

Concentrations of Credit Risk

Financial instruments that potentially subject the Company to significant concentration of credit risk consist primarily of cash, cash equivalents and marketable securities. The Company maintains deposits in financial institutions in excess of government insured limits. Management believes that the Company is not exposed to significant credit risk as the Company’s cash and cash equivalents are held at financial institutions that management believes to be of high credit quality. The Company has not experienced any losses due to credit risk on such accounts during any of the periods presented.

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Fair Value of Financial Instruments

The Company’s financial assets and liabilities are accounted for in accordance with Accounting Standards Codification (“ASC”) 820, Fair Value Measurements and Disclosures, which defines fair value as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. The fair value hierarchy requires an entity to maximize the use of observable inputs when measuring fair value and classifies those inputs into three levels:

Level 1 — Observable inputs, such as quoted prices in active markets for identical assets or liabilities.

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

Level 3 — Unobservable inputs in which there is little or no market data, which require the reporting entity to develop its own assumptions.

To the extent the valuation is based on models or inputs that are less observable or unobservable in the market, the determination of fair values requires more judgment. Accordingly, the degree of judgment exercised by management in determining fair value is greatest for instruments categorized as Level 3. A financial instrument’s level within the fair value hierarchy is based on the lowest level of any input that is significant to the fair value measurement. There were no transfers made among the three levels in the fair value hierarchy for the years ended December 31, 2023 and 2022.

The carrying values reported in the balance sheets for cash (excluding cash equivalents which are recorded at fair value on a recurring basis), restricted cash, accounts payable, accrued clinical trial expenses and accrued expenses are reasonable estimates of their fair values due to the short-term nature of these items.

The carrying amount of the Company’s long-term debt approximates fair value due to its variable market interest rate and management’s opinion that current rates and terms that would be available to the Company with the same maturity and security structure would be essentially equivalent to that of the Company’s long-term debt. Certain features of the term loan were determined to be an embedded derivative requiring separate measurement from the loan host instrument.

Property and Equipment

Property and equipment are stated at cost. Depreciation expense is computed using the straight-line method over the estimated useful lives of the assets, including leasehold improvements and finance lease right-of-use assets that are amortized over the shorter of their estimated useful lives or the terms of the respective leases. The Company generally uses the following useful lives for its property and equipment categories: three years for computer-related assets and five years for furniture. See Note 7. Leases for additional discussion regarding our finance lease for computer equipment.

Leases

The Company accounts for its leases under ASC 842, Leases. Under this guidance, arrangements meeting the definition of a lease are classified as operating or finance leases and are recorded in the balance sheet at the commencement date as both a right-of-use asset and a lease liability, calculated by discounting fixed lease payments over the lease term at the rate implicit in the lease or the Company’s incremental borrowing rate. Lease liabilities are increased by interest and reduced by payments each period, and right-of-use assets are amortized over the lease term, or, for finance leases, over the shorter of the lease term or the estimated useful life of the assets. For operating leases, interest on the lease liability and the amortization of the right-of-use asset results in straight-line rent expense over the lease term. For finance leases, the right-of-use asset is amortized on a straight-line basis and the amortization is presented as an operating expense separately from interest expense on the lease liability. Variable lease expenses are recorded when incurred and not included in the measurement of right-of-use assets and lease liabilities.

ASC 842 provides practical expedients for an entity’s ongoing accounting. In calculating right-of-use assets and lease liabilities, the Company has elected to combine lease and non-lease components for real estate leases, but has not elected to combine lease and non-lease components for computer equipment leases. Additionally, the Company has elected not to

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recognize a right-of-use asset or lease liability for leases with an initial term of 12 months or less. For short-term leases, the Company recognized lease payments on a straight-line basis over the lease term.

Debt Discount and Debt Issuance Costs

The debt discount, which reduces the related debt balance in the balance sheets, is comprised of debt issuance costs, contractual fees due upon repayment of the debt, the issuance date fair value of warrants issued with the debt and the issuance date fair value of any derivatives that are bifurcated from the debt. Debt issuance costs include direct costs (e.g., legal costs and bank fees) incurred to issue non-revolving debt instruments. The debt discount is amortized to interest expense over the contractual term of the related debt using the effective interest method.

Embedded Derivatives

The Company evaluates embedded derivatives within debt to determine whether the embedded derivatives should be bifurcated from the host instrument and accounted for as a derivative at fair value that will be remeasured at each reporting period for the term of the loan, with changes in fair value recorded in the statements of operations and comprehensive loss. Management initially assesses the probability of the occurrence of trigger events for bifurcated embedded derivatives in determining fair value. The probability is reassessed at each reporting period during the term of a loan.

Common Stock Warrant

The Company assesses whether warrants issued require accounting as derivatives. The Company determined that its warrant to purchase Common Stock is not a liability within the scope of ASC 480, Distinguishing Liabilities from Equity, but met the requirements to be classified within stockholders’ equity, as the warrant is indexed to the Company’s own stock and met all of the conditions for equity classification in accordance with ASC 815, Derivatives and Hedging.

Research and Development Expenses

Research and development (“R&D”) expenses primarily consist of consultants and materials, biologic storage, salaries and other personnel-related expenses related to R&D activities and are expensed as incurred. Payments for these activities are based on the terms of the individual agreements, which may differ from the pattern of costs incurred, and are reflected on the balance sheets as prepaid or accrued expenses. The Company records accruals for estimated ongoing research costs. When evaluating the adequacy of the accrued liabilities, the Company analyzes progress of the studies, including the phase or completion of events, invoices received and contracted costs.

Clinical trial costs are a significant component of R&D expenses and include costs associated with third-party contractors. The Company accrues and expenses costs for clinical trial activities performed by third parties based upon the work completed to date for each clinical trial in accordance with established agreements. The Company determines its costs through discussions with internal clinical stakeholders and outside service providers as to the progress or stage of completion of clinical trials or services and the contracted fee to be paid for such services. In the event advance payments are made to an outside service provider, the payments are recorded within prepaid expenses and other current assets in the balance sheetsand subsequently recognized as R&D expense in the statements of operationsand comprehensive loss when the associated services have been performed. As actual costs become known, the Company adjusts its estimates, liabilities and assets. Inputs used in the determination of estimates discussed above may vary from actual, which will result in adjustments to R&D expense in future periods.

Stock-based Compensation

The Company expenses stock-based compensation to employees, non-employees and board members over the requisite service period based on the estimated grant date fair value of the awards and actual forfeitures. The Company estimates the fair value of stock option grants using the Black-Scholes option pricing model, which requires the use of a number of complex assumptions including the fair value of the Common Stock, expected volatility, risk-free interest rate, expected dividends, and the expected term of the option. The fair value of restricted stock units (“RSUs”) is the closing market price of the Common Stock on the date of the grant. The assumptions used in calculating the fair value of stock-based awards represent management’s best estimates and involve inherent uncertainties and the application of management’s judgment. Stock-based awards with graded-vesting schedules are recognized on a straight-line basis over the requisite service period.

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All stock-based compensation costs are recorded in research and development expense or general and administrative expense in the Statements of Operations and Comprehensive Loss based upon the respective employee’s or non-employee’s roles within the Company. Forfeitures are recorded as they occur. See also Note 9. Stock-based Compensation below.

Income Taxes

Income taxes are recorded in accordance with ASC 740, Income Taxes (“ASC 740”), which provides for deferred taxes using an asset and liability approach. The Company recognizes deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the financial statements or tax returns. Deferred tax assets and liabilities are determined based on the difference between the financial statement and tax bases of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse, and net operating loss (“NOL”) carryforwards and R&D tax credit carryforwards. Valuation allowances are provided if, based upon the weight of available evidence, it is more likely than not that some or all of the deferred tax assets will not be realized. The Company has recorded a full valuation allowance to reduce its net deferred income tax assets to zero. In the event the Company were to determine that it would be able to realize some or all of its deferred income tax assets in the future, an adjustment to the deferred income tax asset valuation allowance would increase income in the period such determination was made.

The Company accounts for uncertain tax positions in accordance with the provisions of ASC 740. When uncertain tax positions exist, the Company recognizes the tax benefit of tax positions to the extent that the benefit would more likely than not be realized assuming examination by the taxing authority. The determination as to whether the tax benefit will more likely than not be realized is based upon the technical merits of the tax position as well as consideration of the available facts and circumstances. The Company has not recorded any liabilities related to uncertain tax positions as of December 31, 2023 and 2022. The Company’s policy is to record interest and penalties, if any, as part of income tax benefit. No interest or penalties were recorded during the years ended December 31, 2023 and 2022.

Net Loss Per Share of Common Stock

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 the period. Diluted net loss per share of common stock includes the effect, if any, from the potential exercise or conversion of securities, such as convertible debt, stock options, restricted stock units and warrants, which would result in the issuance of incremental shares of common stock. However, potential shares of common stock are excluded if their effect is anti-dilutive. 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. For the year ended December 31, 2023, potential common shares consisted of stock options, restricted stock units, convertible debt and a warrant to purchase Common Stock. For the year ended December 31, 2022, potential shares of common stock consisted of stock options.

Potentially dilutive securities not included in the calculation of diluted net loss per share of common stock as of the periods presented, because to do so would be anti-dilutive, were as follows:

December 31,

Shares issuable upon conversion election for Term Loan 988,142 —

Shares issuable upon exercise of warrant 730,769 —

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 its operations and manages its business in one segment.

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Recently Adopted Accounting Pronouncements

In June 2016, the FASB issued Accounting Standards Update 2016-13, Financial Instruments-Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments, which was codified with its subsequent amendments as ASC 326. ASC 326 seeks to provide financial statement users with more decision-useful information about the expected credit losses on financial instruments, including trade receivables, and other commitments to extend credit held by a reporting entity at each reporting date. The amendments require an entity to replace the incurred loss impairment methodology in current U.S. GAAP with a methodology that reflects current expected credit losses and requires consideration of a broader range of reasonable and supportable information to inform credit loss estimates. The Company adopted this guidance on January 1, 2023. The Company’s marketable securities portfolio consists entirely of available-for-sale debt securities and, as such, the adoption of this guidance did not have a material impact on its financial statements and disclosures upon adoption, but it did require the Company to provide additional disclosures related to its available-for-sale debt securities in a continuous unrealized loss position.

In August 2020, the FASB issued ASU 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”), to address the complexity associated with applying U.S. GAAP to certain financial instruments with characteristics of liabilities and equity. ASU 2020-06 includes amendments to the guidance on convertible instruments and the derivative scope exception for contracts in an entity’s own equity and simplifies the accounting for convertible instruments, which include beneficial conversion features or cash conversion features by removing certain separation models in Subtopic 470-20. Additionally, ASU 2020-06 requires entities to use the “if-converted” method when calculating diluted earnings per share for convertible instruments. The Company early adopted this guidance on January 1, 2023, with no impact to the financial statements or results of operations of the Company.

NOTE 3. MARKETABLE SECURITIES

The Company’s marketable securities consisted of the following (in thousands):

Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value

Available-for-sale securities, short-term

Available-for-sale securities, long-term

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Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value

Available-for-sale securities, short-term

Total available-for-sale securities, short-term 48,212 — (708) 47,504

Available-for-sale securities, long-term

Total available-for-sale securities, long-term 15,880 — (43) 15,837

The following tables summarize the amount of unrealized losses, defined as the amount by which the amortized cost exceeds fair value, and the related fair value of available-for-sale marketable securities with unrealized losses, which have been segregated into two categories: those that have been in a continuous unrealized loss position for less than 12 months and those that have been in a continuous unrealized loss position for 12 or more months (in thousands):

Less than 12 Months Greater than 12 Months Total

Government and agency - U.S. securities 5,585 (6) — — 5,585 (6)

Less than 12 Months Greater than 12 Months Total

As of December 31, 2023, the Company’s available-for-sale securities classified as short-term mature in one year or less and the Company’s available-for-sale securities classified as long-term mature within two years. As noted in the table above, although some of the Company’s available-for-sale marketable securities as of December 31, 2023 have been in an unrealized loss position for more than 12 months, the Company does not intend to sell these securities and it is not more likely than not that the Company will be required to sell the investments before recovery of their amortized cost bases, which may be at maturity. No credit losses were recognized on the Company’s available-for-sale securities during the years ended December 31, 2023 and 2022. The Company recorded an immaterial realized gain during the year ended December 31, 2023 and had no realized gains or losses during the year ended December 31, 2022.

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NOTE 4. FAIR VALUE MEASUREMENTS

The Company’s financial assets and liabilities subject to fair value measurement on a recurring basis and the level of inputs used for such measurements were as follows (in thousands):

Fair value measurements at reporting date using

Assets included in:

Cash and cash equivalents

Marketable securities

Liabilities included in:

Debt, long-term

Embedded derivative liabilities $ — $ — $ 2,560 $ 2,560

Fair value measurements at reporting date using

Assets included in:

Cash and cash equivalents

Marketable securities

The fair value of the Company’s money market funds is determined using quoted market prices in active markets for identical assets.

The fair value for the available-for-sale marketable securities is determined based on valuation models using inputs that are observable either directly or indirectly (Level 2 inputs), such as quoted prices for similar assets or liabilities, yield curve, volatility factors, credit spreads, default rates, loss severity, current market and contractual prices for the underlying instruments or debt, broker and dealer quotes, as well as other relevant economic measures.

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The following table presents changes in Level 3 liabilities measured at fair value for the year ended December 31, 2023 (in thousands):

Balance, January 1, 2023 $ —

Fair value of embedded derivatives at issuance of Term Loan 1,200

Change in fair value of embedded derivatives 1,360

For the year ended December 31, 2023, the fair value of the embedded derivatives in the Term Loan has been estimated using the Monte Carlo model. A summary of the weighted-average significant unobservable inputs (Level 3 inputs) used in measuring the embedded derivatives in the Term Loan as of December 31, 2023 and November 10, 2023 (inception) is as follows:

December 31, November 10,

Expected term (in years) 4.7 4.9

Risk-free interest rate 3.9% 4.7%

Discount for lack of marketability 11.5% 9.5%

Expected dividend yield 0% 0%

NOTE 5. SUPPLEMENTAL FINANCIAL INFORMATION

Prepaid expenses and other current assets consisted of the following (in thousands):

December 31,

Research and development service agreements $ 1,680 $ 1,077

Interest receivable 225 —

Prepaid raw materials 98 199

Total prepaid expenses and other current assets $ 3,093 $ 2,724

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

December 31,

Compensation and other employee liabilities $ 3,692 $ 2,008

Total accrued expenses and other current liabilities $ 6,339 $ 3,350

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NOTE 6. DEBT

Term Loan

On November 10, 2023, the Company entered into a Loan and Security Agreement with K2 HealthVentures LLC (the “Loan Agreement”). The Loan Agreement provided the Company with a term loan facility (the “Term Loan”) in the aggregate principal amount of $50.0 million, of which the Company borrowed $30.0 million in the first tranche upon closing. The remaining $20.0 million is available for borrowing upon the Company’s request based on review of certain information and discretionary approval from the lenders. The Loan Agreement bears interest per annum at the greater of 9.65% or the sum of the prime rate last quoted in The Wall Street Journal plus 1.15% for such interest period and the principal amount of Term Loan outstanding under the Loan Agreement. The Term Loan matures on November 1, 2027, and can be extended to November 1, 2028, if the Company achieves certain financing milestones. The Loan Agreement provides for a final payment fee of an additional $1.6 million (the “Final Payment”) due upon repayment of the Term Loan.

The principal and interest of the Term Loan are to be repaid in equal monthly installments beginning on July 1, 2026 through the maturity of the Loan Agreement. The Loan Agreement allows prepayments of the entire Term Loan or a portion of the Term Loan of more than $5.0 million, provided that any partial prepayment will leave outstanding borrowings of at least $15.0 million.

The lenders can elect to convert up to $2.5 million of the Term Loan (the “Conversion Amount”) to Common Stock at a conversion price of $2.53 (the “Conversion Option”). If the lenders elect to convert the Conversion Amount upon the Next Qualified Financing, as defined in the Loan Agreement whereby the Company receives aggregate gross proceeds of at least $20.0 million, the conversion price will equal the lowest effective cash price per share of securities issued in such Qualified Financing (the “Share-Settled Redemption”). The Conversion Option and Share-Settled Redemption within the Loan Agreement are required to be bifurcated as a single compound embedded derivative (the “Embedded Derivatives”) at fair value, with subsequent changes in fair value recognized in the statements of operations and comprehensive loss.

In accordance with the Loan Agreement, the Company issued an equity-classified warrant to purchase 730,769 shares of Common Stock (the “Loan Warrant”), with an initial allocated fair value of $1.1 million. See additional discussion in Note 8. Stockholders’ Equity.

The initial recognition of the direct fees of $0.5 million, the Final Payment of $1.6 million, the fair value of the Embedded Derivatives of $1.2 million and the fair value of the Loan Warrant of $1.1 million for the Loan Agreement resulted in a discount of $4.4 million, which is being amortized to interest expense over the term of the Loan Agreement using the effective interest method.

Outstanding debt consisted of the following (in thousands):

Principal value of Term Loan, including final payment of $1,635 $ 31,635

Fair value of bifurcated embedded derivatives 2,560

Unamortized debt discount (4,298)

Total debt, long-term $ 29,897

The following table provides the components of interest expense (in thousands):

Year Ended

Interest expense based on the coupon interest rate of the outstanding debt $ 418

Accretion of debt discount 145

Total interest expense $ 563

For the year ended December 31, 2023, the effective interest rate for the Term Loan was 14.3%.

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As of December 31, 2023, the aggregate principal payments due for the Term Loan by year are as follows (in thousands):

Total principal payment due for Term Loan $ 31,635

NOTE 7. LEASES

Office leases

On September 11, 2023, the Company entered into a lease for office space in Newton, Massachusetts, with a lease term of approximately 38 months beginning October 20, 2023, and which expires on December 31, 2026.

On September 28, 2022, the Company entered into a lease for office space in Charlottesville, Virginia with a lease term of 15 months beginning October 1, 2022. On December 1, 2022, the Company entered into a lease for additional office space in the same building in Charlottesville, Virginia with a lease term of 12 months beginning on January 1, 2023. There is no automatic renewal for either of the Charlottesville, Virginia leases, but the lease agreements provide that any holdover tenancy shall be on a month-to-month basis thereafter.

The Company had been subleasing space in Carmel, Indiana since March 1, 2020. The Company executed a new sublease for this space that was effective on February 1, 2021 and expired on August 30, 2023, at which time the Company ceased to occupy this space. The Company allowed others to sublease a portion of the space from the Company for less than a one-year period. The Company recognizes sublease income in other expense, net in the statements of operations and comprehensive Loss.

Computer Equipment Lease

In September 2023, the Company entered into an agreement with a vendor that included the lease of certain computer equipment for its planned Phase 2 clinical trial with an October 2023 lease commencement date. In January 2024, the Company paid $0.8 million for the computer equipment which will be returned to the vendor at the completion of the vendor’s services under the agreement. Upon the lease inception, the Company recorded non-cash expense of $0.7 million in research and development expense in the statement of operations and comprehensive loss for the right-of-use assets related to the computer equipment lease as the equipment is being used for R&D and does not have an alternative future use.

The following table summarizes quantitative information about the Company’s leases (in thousands):

Year Ended December 31,

Finance lease

Interest lease cost $ 17 $ —

Finance lease expense 17 —

Operating leases

Less: sublease income (5) (43)

Operating lease expense 128 111

Short-term lease rent expense 15 13

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Supplemental information related to leases was as follows (dollar amounts in thousands):

Year Ended December 31,

Operating cash flows from finance lease $ 17 $ —

Operating cash flows from operating leases $ 121 $ 154

Right-of-use assets obtained in exchange for finance lease liabilities $ 739 $ —

Weighted-average remaining lease term – finance leases (in years) 3.8 —

Weighted-average remaining lease term – operating leases (in years) 3.0 0.7

Weighted-average discount rate – finance leases 9.7 % —

Weighted-average discount rate – operating leases 9.7 % 10.0 %

As of December 31, 2023, the present value of maturities of the Company’s finance lease liabilities were as follows (in thousands):

Less: present value discount (7)

Finance lease liability $ 756

As of December 31, 2023, the present value of maturities of the Company’s operating lease liabilities were as follows (in thousands):

Less: present value discount (63)

Operating lease liability $ 393

NOTE 8. STOCKHOLDERS’ EQUITY

Authorized Shares

As of December 31, 2023, the total number of shares of capital stock authorized to be issued per the Company’s Amended and Restated Certificate of Incorporation is 310,000,000, with 10,000,000 shares designated as preferred stock with a par value of $0.0001, and 300,000,000 shares designated as Common Stock.Each share of Common Stock issued and outstanding is entitled to one vote.

Public Offering

On July 21, 2023, the Company issued 16,774,193 shares of its Common Stock in a public offering (the “Offering”) at a price of $7.75 per share. The aggregate net proceeds from the Offering, after underwriting discounts and commissions and other offering expenses, were $121.9 million.

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Shelf Registration and At-The-Market Equity Offering

On July 1, 2022, the Company filed a shelf registration statement on Form S-3 (the “Registration Statement”). Pursuant to the Registration Statement, the Company may offer and sell securities having an aggregate public offering price of up to $200.0 million. In connection with the filing of the Registration Statement, the Company also entered into a sales agreement (the “Sales Agreement”) with BofA Securities, Inc. (“BofA”) and Stifel, Nicolaus & Company, Incorporated (“Stifel”), as sales agents, pursuant to which the Company may issue and sell shares of its Common Stock for an aggregate offering price of up to $50.0 million under an at-the-market offering program (the “ATM”), which is included in the $200.0 million of securities that may be offered pursuant to the Registration Statement. On April 23, 2023, the Company entered into an amendment to the Sales Agreement (as amended, the “Amended Sales Agreement”) to add BTIG, LLC (“BTIG”) as a sales agent under the Amended Sales Agreement (BTIG, together with BofA and Stifel, the “Sales Agents”). Pursuant to the Amended Sales Agreement, the Company will pay the Sales Agents a commission rate of up to 3.0% of the gross proceeds from the sale of any shares of Common Stock. The Company is not obligated to make any sales of shares of its common stock under the ATM.

The Company did not sell any shares of its Common Stock under the ATM during the year ended December 31, 2023. In October 2022, the Company issued 422,160 shares of common stock under the ATM for net proceeds of $3.8 million, at a weighted average price of $10.06 per share. See additional discussion in Note 12. Subsequent Events.

Common Stock Warrant

On November 10, 2023, in accordance with the Loan Agreement, the Company issued the Loan Warrant to purchase 730,769 shares of Common Stock at an exercise price of $1.95 with a ten-year contractual term and an allocated fair value of $1.1 million. This warrant is outstanding as of December 31, 2023. In accordance with ASC 815, the Loan Warrant issued in 2023 did not meet the definition of a derivative and was classified in stockholders’ equity in the balance sheet.

The Black-Scholes option-pricing model was used to estimate the fair value of the warrant on November 10, 2023 with the following weighted average assumptions:

Risk-free interest rate 4.6%

Contractual term (in years) 10

Expected volatility 98.4%

Expected dividend yield 0%

NOTE 9. STOCK-BASED COMPENSATION

2021 Equity Incentive Plan

The 2021 Equity Incentive Plan (the “2021 Plan”), which provides for the grant of incentive stock options to employees, and the grant of nonstatutory stock options, stock appreciation rights, restricted stock awards, restricted stock unit awards, performance awards and other forms of stock awards to employees, directors and consultants, became effective on June 30, 2021. The 2021 Plan is a successor to the Company’s Amended and Restated Stock Performance Plan that was adopted by the Company’s board of directors (“Board”) and stockholders on April 8, 2013 (as amended from time to time, most recently on November 20, 2020, the “2013 Plan”). Following the effectiveness of the 2021 Plan, no further grants may be made under the 2013 Plan; however, any outstanding equity awards granted under the 2013 Plan continue to be governed by the 2013 Plan. As of December 31, 2023, there were 3,231,274 options outstanding under the 2013 Plan.

The number of shares of Common Stock reserved for issuance under the 2021 Plan automatically increases on January 1 of each calendar year through January 1, 2031, in an amount equal to 5% of the total number of shares of Common Stock outstanding on December 31 of the fiscal year before the date of each automatic increase, or a lesser number of shares determined by the Board prior to the applicable January 1. On January 1, 2023, the number of shares of Common Stock reserved for issuance under the 2021 Plan automatically increased by 2,051,253 shares.

The maximum number of shares of Common Stock that may be issued upon the exercise of incentive stock options under the 2021 Plan is 12,000,000. As of December 31, 2023, 11,773,198 shares were authorized for issuance under the 2021 Plan and 3,674,730 shares remained available for issuance under the 2021 Plan.

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The Company recorded stock-based compensation expense related to stock options and RSUs in the following expense categories of the statements of operations and comprehensive loss for the periods shown (in thousands):

Year Ended December 31,

General and administrative $ 4,288 $ 2,163

Total stock-based compensation $ 6,145 $ 3,061

Stock Options

The Black-Scholes option-pricing model was used to estimate the fair value of stock options granted during the years ended December 31, 2023 and 2022 with the following weighted average assumptions:

Year Ended December 31,

Risk-free interest rate 3.5% – 4.7% 1.7% – 4.2%

Expected term (in years) 5.5 – 6.1 5.8 – 6.1

Expected volatility 90% - 98% 90%

Expected dividend yield 0% 0%

The weighted average grant date fair value of options granted during the years ended December 31, 2023 and 2022 was $4.38 per share and $3.79 per share, respectively.

Stock options granted after December 31, 2017 generally vest monthly over a range of 12 to 48 months or vest monthly over a total of 48 months following a one-year cliff and all have a ten-year contractual term. During the year ended December 31, 2023, the Company also issued option awards to members of its Board that vest in full on the first anniversary of the grant date. Stock options granted prior to December 31, 2017 were either fully vested upon grant or generally vested monthly over a range of three to 24 months and have a ten-year term. The Company became publicly traded in July 2021 and lacks sufficient company-specific historical and implied volatility information. Therefore, it estimates its expected stock volatility using a weighted average blend of historical volatility of a publicly traded set of peer companies, as well as its own historical volatility. Due to the lack of historical exercise history, the expected term of the Company’s stock options has been determined using the “simplified” method for awards. The risk-free interest rate is determined by reference to the U.S. Treasury yield curve in effect at the time of grant of the award for time periods approximately equal to the expected term of the award. Expected dividend yield is zero based on the fact that the Company has never paid cash dividends and does not expect to pay any cash dividends in the foreseeable future.

The following table reflects summarized stock option activity:

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The intrinsic value of stock options exercised during the years ended December 31, 2023 and 2022 was approximately $0.5 million and $0.6 million, respectively. As of December 31, 2023, total unrecognized compensation costs related to unvested stock option awards granted was approximately $12.3 million, which the Company expects to recognize over a weighted-average period of approximately 2.2 years.

Restricted Stock Units

In January 2023, the Company granted a RSU award to each of its then-current employees. These RSU awards vest in equal annual installments on the first three anniversaries of the grant date.

Number of Shares Weighted Average Grant Date Fair Value

Unvested as of January 1, 2023 — $ —

As of December 31, 2023, total unrecognized compensation costs related to unvested RSUs was approximately $1.4 million, which the Company expects to recognize over a weighted-average period of approximately 2.1 years.

Employee Stock Purchase Plan

The 2021 Employee Stock Purchase Plan (the “ESPP”), which permits employees to purchase shares of Common Stock, became effective on June 30, 2021. The number of shares of Common Stock reserved for issuance automatically increases on January 1 of each calendar year through January 1, 2031, by the lesser of (1) 1% of the total number of shares of Common Stock outstanding on the last day of the fiscal year before the date of the automatic increase, and (2) 800,000 shares; provided that before the date of any such increase, the Board may determine that such increase will be less than the amount set forth in clauses (1) and (2). On January 1, 2023, the number of shares of Common Stock reserved for issuance under the ESPP automatically increased by 410,251 shares. As of December 31, 2023, there are a total of 1,189,983 shares authorized for issuance and there have been no purchases of shares under the ESPP.

NOTE 10. INCOME TAXES

The Company has not recorded any tax provision or benefit for federal income taxes for the years ended December 31, 2023 and 2022. Current income taxes are based upon the year’s income taxable for federal and state tax reporting purposes. Deferred income taxes (benefits) are provided for certain income and expenses, which are recognized in different periods for tax and financial reporting purposes. Deferred tax assets and liabilities are computed for differences between the financial statements and tax bases of assets and liabilities that will result in taxable or deductible amounts in the future based on enacted tax laws and rates applicable to the period in which the differences are expected to affect taxable income, and NOL and R&D tax credit carryforwards.

A reconciliation of the expected tax computed at the U.S. statutory federal income tax rate to the total benefit for income taxes for the years ended December 31, 2023 and 2022 is as follows:

Year Ended December 31,

Statutory federal income tax rate 21.0 % 21.0 %

State tax, net of federal benefit 2.5 2.7

Non-deductible stock compensation (0.4) (0.5)

Rate change (0.1) (1.1)

Other (0.5) —

Change in valuation allowance (22.5) (22.1)

Income tax provision 0.0 % 0.0 %

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Significant components of the Company’s deferred tax assets as of December 31, 2023 and 2022 were as follows (in thousands):

December 31,

Deferred tax assets:

Intangible assets 441 —

Accruals and other temporary differences 575 179

Total deferred tax assets 437 30

Deferred tax liabilities:

Embedded debt derivative liabilities (274) —

Depreciation — (30)

Total deferred tax liabilities (437) (30)

Net deferred tax assets $ — $ —

In assessing the realizability of deferred tax assets as of December 31, 2023 and 2022, management considered whether it is more likely than not that some portion or all of the deferred tax assets will be realized. The ultimate realization of deferred tax assets is dependent upon the generation of future taxable income during the periods in which those temporary differences become deductible or the net operating loss (“NOL”) carryforwards and R&D tax credit carryforwards will be used. The Company has determined that it is not more likely than not that its deferred tax assets will be realized. Accordingly, a valuation allowance for the full amount of the net deferred tax assets has been recorded as of December 31, 2023 and 2022. The change in the valuation allowance as of December 31, 2023 from December 31, 2022 is due to the pretax loss incurred for the year ended December 31, 2023.

As of December 31, 2023, the Company had approximately $67.2 million of NOL carryforwards available for federal tax purposes. As a result of the Tax Act of 2017, for U.S. income tax purposes, NOLs generated prior to December 31, 2017 can still be carried forward for up to 20 years, but NOLs generated after December 31, 2017 carryforward indefinitely, but are limited to 80% utilization against taxable income. Of the total federal NOLs of $67.2 million, $6.5 million will begin to expire on December 31, 2028 and $60.7 million will not expire.

As of December 31, 2023, the Company also had approximately $46.9 million of state NOL carryforwards. The state NOLs begin to expire on December 31, 2028.

As of December 31, 2023, the Company had approximately $1.4 million of R&D credit carryforwards available for federal tax purposes, which begin to expire on December 31, 2024.

Utilization of the NOL and R&D credit carryforwards may be subject to a substantial annual limitation due to ownership change limitations that may have occurred or that could occur in the future, as required by Sections 382 and 383 of the Internal Revenue Code of 1986, as amended (the “Code”), as well as similar state provisions. These ownership changes may limit the amount of NOL and R&D credit carryforwards that can be utilized annually to offset future taxable income and tax, respectively. In general, an “ownership change” as defined by Section 382 of the Code results from a transaction or series of transactions over a three-year period resulting in an ownership change of more than 50% of the outstanding stock of a company by certain stockholders. The Company has not completed a formal analysis of the potential impact of Section 382 on its deferred tax assets as of December 31, 2023. Until this analysis has been completed, the Company has

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not adjusted any of its deferred tax assets, including NOLs or R&D credits. The Company will reassess the amount of NOLs and credits subject to limitation under Section 382 when a study is complete. Due to the existence of the valuation allowance, future changes in the deferred tax assets related to these tax attributes will not impact the Company’s effective tax rate.

The Company is subject to U.S. federal and various state taxes. Generally, the tax years remain open for examination by the federal statute under a three-year statute of limitation; however, states generally keep their statutes open for four years. However, the Company’s tax years from 2004 and after are subject to examination by the United States and state taxing authorities due to the carry forward of unused NOLs and R&D credits.

NOTE 11. COMMITMENTS AND CONTINGENCIES

The Company is not a party to any material legal proceedings and is not aware of any pending or threatened claims. From time to time, the Company may be subject to various legal proceedings and claims that arise in the ordinary course of its business activities.

In November 2023, the Company entered into a Non-exclusive Collaboration and License Agreement (the “Halozyme License Agreement”) with Halozyme, Inc. (“Halozyme”). Under the terms of the Halozyme License Agreement, Halozyme granted the Company a non-exclusive license to Halozyme’s drug delivery technology for the development of a subcutaneous formulation of sabirnetug (such combination, the “Halozyme Product”). For the year ended December 31, 2023, the Company recorded R&D expense with an offsetting accrual in accrued expenses and other current liabilities as of December 31, 2023, for the majority of the seven-figure upfront license payment for the Halozyme Product (the “Upfront Payment”), as the Halozyme Product is in its development stage and does not have an alternative future use. See Note 12. Subsequent Events for more information regarding the Upfront Payment. Additionally, the Company will make milestone payments tied to achievement of certain development and commercialization milestone events with respect to the Halozyme Product, as well as milestone payments based on achievement of certain net sales levels of the Halozyme Product. The Company will also make single-digit royalty payments based on worldwide net sales of the Halozyme Product.

In November 2022, the Company entered into a License Agreement (“Lonza License Agreement”) with Lonza Sales AG (“Lonza”). Under the terms of the Lonza License Agreement, Lonza granted the Company a worldwidenon-exclusive license to use Lonza’s glutamine synthetase gene expression system to manufacture and commercialize sabirnetug (the “Lonza Product”). Under the terms of the Lonza License Agreement, in consideration of the licenses and consents granted to the Company, the Company paid an upfront fee of 1.0 million Swiss Francs. The Company is also required to pay certain royalties upon commercialization and annual payments on a country-by-country basis in respect of the manufacturing and sale of the Lonza Product, which include (i) a royalty of less than 1% on net sales where Lonza manufactures the Lonza Product, (ii) an annual royalty payment in Swiss Francs in the low six-digits and a royalty of less than 1% on net sales where the Company manufactures the Lonza Product and (iii) an annual payment in Swiss Francs in the mid six-digits per sublicense and a royalty on net sales in the low single digits where a third party manufactures the Lonza Product. These payment obligations would expire ten years from the first commercial sales of the Lonza Product in such country of sale.

NOTE 12. SUBSEQUENT EVENTS

In January 2024, the Company issued 2,068,246 shares of Common Stock under the ATM for net proceeds of $7.9 million, or $3.84 per share.

In January 2024, the Company paid the seven-figure Upfront Payment for the Halozyme Agreement. See Note 11. Commitments and Contingencies for additional information.

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Item 9. Changes in and Disagreements With Accountants on Accounting and Financial Disclosure.

None.

Item 9A. Controls and Procedures.

Evaluation of Disclosure Controls and Procedures

We maintain “disclosure controls and procedures,” as defined in Rule 13a-15(e) and Rule 15d-15(e) under the Exchange Act that are designed to ensure that information required to be disclosed by a company in the reports that it files or submits under the Exchange Act is recorded, processed, summarized and reported, within the time periods specified in the SEC’s rules and forms. Disclosure controls and procedures include, without limitation, controls and procedures designed to ensure that information required to be disclosed by a company in the reports that it files or submits under the Exchange Act is accumulated and communicated to our management, including our principal executive and principal financial officers, as appropriate to allow timely decisions regarding required disclosure.

Our management, with the participation of our principal executive officer and principal financial officer, evaluated the effectiveness of our disclosure controls and procedures (as defined in Rules 13a-15(e) and 15d-15(e) under the Securities Exchange Act of 1934, as amended) as of December 31, 2023. Based on the evaluation of our disclosure controls and procedures, our management concluded that, as of December 31, 2023, our disclosure controls and procedures were effective to provide reasonable assurance that the information required to be disclosed by us in this Annual Report on Form 10-K was (a) reported within the time periods specified by SEC rules and regulations, and (b) communicated to our management, including our Chief Executive Officer and Chief Financial Officer, to allow timely decisions regarding any required disclosure.

Management’s Annual Report on Internal Control Over Financial Reporting

Our management is responsible for establishing and maintaining adequate internal control over financial reporting. Internal control over financial reporting is defined in Rule 13a-15(f) and 15d-15(f) under the Exchange Act, as a process designed by, or under the supervision of, our principal executive and principal financial and accounting officers and effected by our board of directors and management to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles and includes those policies and procedures that (i) pertain to the maintenance of records that, in reasonable detail, accurately and fairly reflect the transactions and dispositions of our assets; (ii) provide reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with U.S. GAAP, and that receipts and expenditures are being made only in accordance with authorizations of our management and directors; and (iii) provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use or disposition of our assets that could have a material effect on our financial statements.

Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with policies or procedures may deteriorate. Our management assessed the effectiveness of our internal control over financial reporting as of December 31, 2023. In making this assessment, management used the criteria set forth by the Committee of Sponsoring Organizations of the Treadway Commission, or COSO, in the original Internal Control—Integrated Framework updated in 2013. Based on that assessment, our management concluded that our internal control over financial reporting was effective as of December 31, 2023.

Changes in Internal Control Over Financial Reporting

There were no changes in our internal control over financial reporting (as defined in Rules 13a-15(f) and 15d-15(f) under the Exchange Act) that occurred during the fiscal quarter ended December 31, 2022 that have materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.

Attestation Report on Internal Control over Financial Reporting

This Annual Report on Form 10-K does not include an attestation report of our independent registered public accounting firm on internal control over financial reporting as we are not subject to section 404(b) of the Sarbanes-Oxley Act of 2002 due to our status as a “smaller reporting company” and “Non-accelerated filer.”

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Item 9B. Other Information.

None.

Item 9C. Disclosure Regarding Foreign Jurisdictions that Prevent Inspections.

Not applicable.

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PART III

Item 10. Directors, Executive Officers and Corporate Governance.

The information required by this item will be contained in our 2024 Proxy Statement, to be filed with the SEC not later than 120 days after the end of our fiscal year ended December 31, 2023, under the captions “Information Regarding the Board of Directors and Corporate Governance,” “Election of Directors” and “Executive Officers” and is incorporated in this report by reference.

Item 11. Executive Compensation.

The information required by this item will be set forth in the 2024 Proxy Statement under the captions “Executive Compensation” and “Director Compensation” and is incorporated herein by reference.

Item 12. Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters.

The information required by this item will be set forth in the 2024 Proxy Statement under the captions “Security Ownership of Certain Beneficial Owners and Management” and “Equity Compensation Plan Information” and is incorporated herein by reference.

Item 13. Certain Relationships and Related Transactions, and Director Independence.

The information required by this item will be set forth in the 2024 Proxy Statement under the captions “Transactions with Related Persons and Indemnification” and “Independence of the Board of Directors” and is incorporated herein by reference.

Item 14. Principal Accountant Fees and Services.

The information required by this item will be set forth in the 2024 Proxy Statement under the caption “Ratification of Selection of Independent Registered Public Accounting Firm” and is incorporated herein by reference.

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PART IV

Item 15. Exhibit and Financial Statement Schedules.

(a)(1) Financial Statements

The financial statements are included in Item 8. “Financial Statements and Supplementary Data.”

(a)(2) Financial Statement Schedules

All schedules are omitted as information required is inapplicable or the information is presented in the financial statements and the related notes.

(a)(3) Exhibits

Exhibit Number Description of Exhibit

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Exhibit Number Description of Exhibit

23.1* Consent of Ernst & Young LLP, independent registered accounting firm.

24.1* Power of Attorney (included on signature page).

97.1* Policy for Recoupment of Incentive Compensation.

101.INS* Inline XBRL Instance Document.

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Exhibit Number Description of Exhibit

101.SCH* Inline XBRL Taxonomy Extension Schema Document.

101.CAL* Inline XBRL Taxonomy Extension Calculation Linkbase Document.

101.DEF* Inline XBRL Taxonomy Extension Definition Linkbase Document.

101.LAB* Inline XBRL Taxonomy Extension Label Linkbase Document.

101.PRE* Inline XBRL Taxonomy Extension Presentation Linkbase Document.

104 Cover Page Interactive Data File (embedded within the Inline XBRL document).

* Filed herewith.

+ Indicates management contract or compensatory plan.

Item 16. Form 10-K Summary.

None.