Acumen Pharmaceuticals, Inc. 10-Q

Item 1. Financial Statements. Acumen Pharmaceuticals, Inc. Condensed Balance Sheets (in thousands, except share and per share data) June 30, 2026 December 31, 2025 (unaudited) ASSETS Current assets Cash and cash equivalents $ 59,443 $ 53,989 Marketable securities 50,754 62,876 Prepaid expenses and other current assets 5,316 5,387 Total current assets 115,513 122,252 Restricted cash 231 231 Other assets, long-term 263 350 Total assets $ 116,007 $ 122,833 LIABILITIES AND STOCKHOLDERS’ EQUITY Current liabilities Accounts payable $ 13,379 $ 554 Accrued clinical trial expenses 6,263 10,616 Accrued expenses and other current liabilities 7,533 10,072 Debt, short-term 19,673 8,765 Total current liabilities 46,848 30,007 Debt, long-term 11,896 22,396 Total liabilities 58,744 52,403 Commitments and contingencies (Note 10) Stockholders’ equity Preferred stock, $ 0.0001 par value; 10,000,000 shares authorized and no shares issued and outstanding as of June 30, 2026 and December 31, 2025 — — Common stock, $ 0.0001 par value; 300,000,000 shares authorized as of June 30, 2026 and December 31, 2025; 72,314,714 and 60,575,369 shares issued and outstanding as of June 30, 2026 and December 31, 2025, respectively 7 6 Additional paid-in capital 557,186 516,803 Accumulated deficit ( 499,917 ) ( 446,462 ) Accumulated other comprehensive (loss) income ( 13 ) 83 Total stockholders’ equity 57,263 70,430 Total liabilities and stockholders’ equity $ 116,007 $ 122,833 The accompanying notes are an integral part of these unaudited condensed financial statements. 4 Table of Contents Acumen Pharmaceuticals, Inc. Condensed Statements of Operations and Comprehensive Loss (in thousands, except share and per share data) (unaudited) Three Months Ended June 30, Six Months Ended June 30, 2026 2025 2026 2025 Operating expenses Research and development $ 27,809 $ 37,125 $ 44,293 $ 62,391 General and administrative 4,747 4,625 9,412 9,729 Total operating expenses 32,556 41,750 53,705 72,120 Loss from operations ( 32,556 ) ( 41,750 ) ( 53,705 ) ( 72,120 ) Other income (expense) Interest income 1,111 2,015 2,175 4,486 Interest expense ( 1,094 ) ( 1,046 ) ( 2,163 ) ( 2,069 ) Change in fair value of embedded derivatives ( 160 ) ( 40 ) 300 150 Other expense, net ( 19 ) ( 129 ) ( 62 ) ( 193 ) Total other (expense) income ( 162 ) 800 250 2,374 Net loss ( 32,718 ) ( 40,950 ) ( 53,455 ) ( 69,746 ) Other comprehensive gain (loss) Unrealized (loss) gain on marketable securities ( 34 ) 8 ( 96 ) 71 Comprehensive loss $ ( 32,752 ) $ ( 40,942 ) $ ( 53,551 ) $ ( 69,675 ) Net loss per common share, basic and diluted $ ( 0.45 ) $ ( 0.68 ) $ ( 0.79 ) $ ( 1.15 ) Weighted-average shares outstanding, basic and diluted 72,250,694 60,573,425 67,759,940 60,549,658 The accompanying notes are an integral part of these unaudited condensed financial statements. 5 Table of Contents Acumen Pharmaceuticals, Inc. Condensed Statements of Changes in Stockholders’ Equity (in thousands, except share data) (unaudited) For the Three Months Ended June 30, 2026 Common Stock Additional Paid-in Capital Accumulated Deficit Accumulated Other Comprehensive Income (Loss) Total Stockholders’ Equity Shares Amount Balance as of March 31, 2026 72,227,580 $ 7 $ 554,647 $ ( 467,199 ) $ 21 $ 87,476 Private placement offering costs — — ( 12 ) — — ( 12 ) Issuance of common stock for restricted stock units 64,000 — — — — — Stock options exercised for cash 23,134 — 27 — — 27 Unrealized loss on marketable securities — — — — ( 34 ) ( 34 ) Stock-based compensation — — 2,524 — — 2,524 Net loss — — — ( 32,718 ) — ( 32,718 ) Balance as of June 30, 2026 72,314,714 $ 7 $ 557,186 $ ( 499,917 ) $ ( 13 ) $ 57,263 For the Three Months Ended June 30, 2025 Common Stock Additional Paid-in Capital Accumulated Deficit Accumulated Other Comprehensive Income Total Stockholders’ Equity Shares Amount Balance as of March 31, 2025 60,573,425 $ 6 $ 509,423 $ ( 353,923 ) $ 15 $ 155,521 Unrealized gain on marketable securities — — — — 8 8 Stock-based compensation — — 2,498 — — 2,498 Net loss — — — ( 40,950 ) — ( 40,950 ) Balance as of June 30, 2025 60,573,425 $ 6 $ 511,921 $ ( 394,873 ) $ 23 $ 117,077 The accompanying notes are an integral part of these unaudited condensed financial statements. 6 Table of Contents Acumen Pharmaceuticals, Inc. Condensed Statements of Changes in Stockholders’ Equity (in thousands, except share data) (unaudited) For the Six Months Ended June 30, 2026 Common Stock Additional Paid-in Capital Accumulated Deficit Accumulated Other Comprehensive Income (Loss) Total Stockholders’ Equity Shares Amount Balance as of December 31, 2025 60,575,369 $ 6 $ 516,803 $ ( 446,462 ) $ 83 $ 70,430 Issuance of common stock in connection with the private placement, net of offering costs of $ 309 10,833,331 1 35,440 — — 35,441 Issuance of common stock for restricted stock units, net of shares withheld for taxes 791,052 — ( 149 ) — — ( 149 ) Stock options exercised for cash 114,962 — 172 — — 172 Unrealized loss on marketable securities — — — — ( 96 ) ( 96 ) Stock-based compensation — — 4,920 — — 4,920 Net loss — — — ( 53,455 ) — ( 53,455 ) Balance as of June 30, 2026 72,314,714 $ 7 $ 557,186 $ ( 499,917 ) $ ( 13 ) $ 57,263 For the Six Months Ended June 30, 2025 Common Stock Additional Paid-in Capital Accumulated Deficit Accumulated Other Comprehensive Income (Loss) Total Stockholders’ Equity Shares Amount Balance as of December 31, 2024 60,094,083 $ 6 $ 506,985 $ ( 325,127 ) $ ( 48 ) $ 181,816 Issuance of common stock for restricted stock units, net of shares withheld for taxes 446,756 — ( 73 ) — — ( 73 ) Stock options exercised for cash 32,586 — 37 — — 37 Unrealized gain on marketable securities — — — — 71 71 Stock-based compensation — — 4,972 — — 4,972 Net loss — — — ( 69,746 ) — ( 69,746 ) Balance as of June 30, 2025 60,573,425 $ 6 $ 511,921 $ ( 394,873 ) $ 23 $ 117,077 The accompanying notes are an integral part of these unaudited condensed financial statements. 7 Table of Contents Acumen Pharmaceuticals, Inc. Condensed Statements of Cash Flows (in thousands) (unaudited) Six Months Ended June 30, 2026 2025 Cash flows from operating activities Net loss $ ( 53,455 ) $ ( 69,746 ) Adjustments to reconcile net loss to net cash used in operating activities: Depreciation 23 31 Stock-based compensation expense 4,920 4,972 Amortization of premiums and accretion of discounts on marketable securities, net ( 161 ) ( 644 ) Change in fair value of embedded derivatives ( 300 ) ( 150 ) Amortization of right-of-use asset 68 61 Realized gain on marketable securities ( 6 ) ( 3 ) Noncash interest expense 708 613 Changes in operating assets and liabilities: Prepaid expenses and other current assets 71 1,714 Other long-term assets ( 4 ) 18 Accounts payable 12,825 ( 3,545 ) Accrued clinical trial expenses ( 4,353 ) ( 4,236 ) Accrued expenses and other liabilities ( 2,539 ) 4,962 Net cash used in operating activities ( 42,203 ) ( 65,953 ) Cash flows from investing activities Purchases of marketable securities ( 40,823 ) ( 38,056 ) Proceeds from maturities and sales of marketable securities 53,016 105,316 Purchases of property and equipment — ( 88 ) Net cash provided by investing activities 12,193 67,172 Cash flows from financing activities Proceeds from private placement, net of offering costs 35,441 — Proceeds from exercise of stock options 172 37 Repurchase of common shares to pay employee withholding taxes ( 149 ) ( 73 ) Net cash provided by (used in) financing activities 35,464 ( 36 ) Net change in cash and cash equivalents and restricted cash 5,454 1,183 Cash and cash equivalents and restricted cash at the beginning of the period 54,220 35,859 Cash and cash equivalents and restricted cash at the end of the period $ 59,674 $ 37,042 Supplemental disclosure of cash flow information Cash paid for income taxes $ — $ — Cash paid for interest $ 1,463 $ 1,464 The accompanying notes are an integral part of these unaudited condensed financial statements. 8 Table of Contents Acumen Pharmaceuticals, Inc. Notes to Condensed Financial Statements (unaudited) 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 targeting 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 (“AβOs”), which are globular assemblies of the amyloid-beta (“Aβ”) peptide that are distinct from Aβ monomers and amyloid plaques. Based on decades of research and supporting evidence, AβOs 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 its Phase 2 ALTITUDE-AD clinical trial, and plans to announce top-line results in late 2026. Top-line results are expected to include the difference compared to placebo after 18 months as measured by the Integrated Alzheimer’s Disease Rating Scale, our primary clinical efficacy endpoint, as well as key secondary endpoints, such as Clinical Dementia Rating – Sum of the Boxes, certain safety measures such as adverse event rates, including rates of amyloid-related imaging abnormalities, and key fluid biomarkers. ALTITUDE-AD is a randomized, double-blind, placebo-controlled, three-arm clinical trial designed to evaluate the clinical efficacy, safety and tolerability of sabirnetug with up to 180 participants per arm for a total of 542 participants with mild cognitive impairment or mild dementia due to AD. Sabirnetug is a recombinant humanized immunoglobulin gamma 2 monoclonal antibody that was designed to selectively target AβOs. In July 2023, the Company announced top-line results from its Phase 1 INTERCEPT-AD clinical trial of sabirnetug, which demonstrated that sabirnetug met the primary and secondary objectives of this clinical trial in 62 participants with early AD. In addition, the Company is investigating a subcutaneous dosing option of sabirnetug, as well as a blood-brain barrier-penetrating, Aβ oligomer-targeted Enhanced Brain Delivery™ (EBD™) therapy for AD. In June 2026, the Company announced the nomination of two EBD development candidates for the treatment of AD pursuant to its collaboration agreement with JCR Pharmaceuticals Co. Ltd. (“JCR”) and the exercise of its option pursuant to the collaboration agreement to license and develop such development candidates. See additional information in Note 10. Commitments and Contingencies. The Company is subject to the uncertainty of whether its intellectual property will develop into successful commercial products. Liquidity, Capital Resources and Going Concern In accordance with Accounting Standards Codification (“ASC”) 205-40, Presentation of Financial Statements-Going Concern , the Company evaluated whether there are conditions and events, considered in the aggregate, that raise substantial doubt about the Company’s ability to continue as a going concern. The Company has incurred operating losses since inception. As of June 30, 2026, the Company had an accumulated deficit of $ 499.9 million and had cash and cash equivalents and marketable securities of $ 110.2 million. The Company expects to incur additional losses for the foreseeable future as it continues its research and development activities and will need to raise additional capital to fully implement its business plan and to fund its operations. 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 to the Company at adequate levels and on a timely basis, or such agreements may not be available on terms acceptable to the Company, or at all. The Company may be required to delay, limit, reduce or terminate its product discovery and development activities or future commercialization efforts if it is unable to maintain sufficient financial resources, and its business, financial condition and results of operations will be materially and adversely affected. The Company expects that its current balance of cash and cash equivalents and marketable securities may not be sufficient to fund its operations for at least 12 months from the date of issuance of these financial statements. The Company’s cash forecast contains estimates and assumptions related to its ongoing clinical trial and other research and development expenses, and the Company cannot predict the amount or timing of all expenditures with certainty. Accordingly, the Company has concluded that substantial doubt exists about its ability to continue as a going concern. The accompanying unaudited condensed financial statements have been prepared on a going concern basis, which contemplates the realization of assets and satisfaction of liabilities in the normal course of business, and do not include any adjustments relating to recoverability and classification of recorded asset amounts or the amounts and classification of liabilities that might be necessary, should the Company be unable to continue as a going concern. 9 Table of Contents Acumen Pharmaceuticals, Inc. Notes to Condensed Financial Statements (unaudited) NOTE 2. BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Basis of Presentation The accompanying unaudited condensed financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) for interim financial information, the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and notes required by U.S. GAAP for complete financial statements. In the opinion of management, the unaudited condensed financial statements reflect all adjustments, which include only normal recurring adjustments, necessary to present fairly the Company’s financial position and results of its operations and its cash flows for the periods presented. Certain information and note disclosures normally included in the Company’s annual financial statements prepared in accordance with U.S. GAAP have been condensed or omitted. These unaudited condensed financial statement results are not necessarily indicative of results to be expected for the full fiscal year or any future period. A description of the Company’s significant accounting policies is included in the Company’s Annual Report. There have been no material changes in the Company’s significant accounting policies to those previously disclosed in the Company’s Annual Report. Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the unaudited condensed 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 of embedded derivatives within the Company’s debt, long-term and accruals for clinical trial expenses and other research and development expenses. 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 $ 59.3 million and $ 53.7 million in cash equivalents as of June 30, 2026 and December 31, 2025, respectively. Restricted cash primarily consists of deposited cash collateral for the Company’s credit card program. 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): June 30, 2026 December 31, 2025 Cash and cash equivalents $ 59,443 $ 53,989 Restricted cash 231 231 Total cash, cash equivalents and restricted cash $ 59,674 $ 54,220 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 10 Table of Contents Acumen Pharmaceuticals, Inc. Notes to Condensed Financial Statements (unaudited) quality. The Company has not experienced any losses due to credit risk on such accounts during any of the periods presented. 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 (“RSUs”) 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. 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: June 30, 2026 2025 Shares issuable upon exercise of stock options 15,441,098 12,539,238 Shares issuable upon conversion election for term loan facility 988,142 988,142 Shares issuable upon exercise of warrant 730,769 730,769 Unvested RSUs 3,058,771 1,917,293 Total 20,218,780 16,175,442 Segment Information Operating segments are defined as components of an enterprise for which separate discrete financial information is available for evaluation by the chief operating decision maker (“CODM”) in deciding how to allocate resources and assess performance. The Company’s CODM is its chief executive officer. The Company has one operating segment focused on the research and development of treatments for AD, including both sabirnetug and its EBD therapy. See Note 9 – Segment Reporting. Recently Issued Accounting Pronouncements From time to time, new accounting pronouncements are issued by the Financial Accounting Standards Board (“FASB”) or other standard setting bodies that the Company adopts as of the specified effective date. Unless otherwise discussed below, the Company does not believe that the adoption of recently issued standards have or may have a material impact on its financial statements and disclosures. In November 2024, the FASB issued Accounting Standards Update (“ASU”) 2024-04, Debt – Debt with Conversion and Other Options (Subtopic 470-20): Induced Conversions of Convertible Debt Instruments. The standard is intended to clarify the requirements for determining whether certain settlements of convertible debt instruments should be accounted for as an induced conversion. The standard is effective for annual periods beginning after December 15, 2025, and for interim periods within those annual reporting periods. As of June 30, 2026, the Company had no induced conversions. The Company adopted this standard on a prospective basis on January 1, 2026. The adoption of this standard did not have a material impact on the Company’s financial statements and related disclosures. In November 2024, the FASB issued ASU 2024-03, Income Statement – Reporting Comprehensive Income – Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses. The standard is intended to require more detailed disclosures about specified categories of expenses, including employee compensation, depreciation and amortization, included in certain expense captions presented on the face of the income statement. The ASU is effective for fiscal years beginning after December 15, 2026, and for interim periods within fiscal years beginning after December 31, 2027. Early adoption is permitted. The amendments may be applied either (1) prospectively to financial statements issued for reporting periods after the effective date of this ASU or (2) retrospectively to all prior periods 11 Table of Contents Acumen Pharmaceuticals, Inc. Notes to Condensed Financial Statements (unaudited) presented in the financial statements. The Company is evaluating the potential impact of this adoption on its financial statements and related disclosures. In December 2025, the FASB issued ASU 2025-11, Interim Reporting - Narrow Scope Improvements. The standard is intended to improve the guidance in Topic 270, Interim Reporting, by improving the navigability of the required interim disclosures and clarifying when that guidance is applicable. The amendments in this update clarify interim disclosure requirements and the applicability of Topic 270. The amendments also provide additional guidance on what disclosures should be provided in interim reporting periods. The amendments in this update are effective for interim reporting periods within annual reporting periods beginning after December 15, 2027. Early adoption is permitted. Upon adoption, the amendments may be applied on a prospective or retrospective basis. The Company is evaluating the potential impact of this adoption on its financial statements and related disclosures. NOTE 3. MARKETABLE SECURITIES The Company’s marketable securities consisted of the following (in thousands): June 30, 2026 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value Available-for-sale securities, short-term Corporate debt securities $ 28,944 $ 10 $ ( 12 ) $ 28,942 Government and agency - U.S. 21,823 — ( 11 ) 21,812 Total available-for-sale securities, short-term $ 50,767 $ 10 $ ( 23 ) $ 50,754 December 31, 2025 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value Available-for-sale securities, short-term Corporate debt securities $ 62,793 $ 88 $ ( 5 ) $ 62,876 Total available-for-sale securities, short-term $ 62,793 $ 88 $ ( 5 ) $ 62,876 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): June 30, 2026 Less than 12 Months Greater than 12 Months Total Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses Corporate debt securities $ 12,395 $ ( 12 ) $ — $ — $ 12,395 $ ( 12 ) Government and agency - U.S. 21,812 ( 11 ) — — 21,812 ( 11 ) Total $ 34,207 $ ( 23 ) $ — $ — $ 34,207 $ ( 23 ) December 31, 2025 Less than 12 Months Greater than 12 Months Total Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses Corporate debt securities $ 6,036 $ ( 3 ) $ 5,119 $ ( 2 ) $ 11,155 $ ( 5 ) Total $ 6,036 $ ( 3 ) $ 5,119 $ ( 2 ) $ 11,155 $ ( 5 ) 12 Table of Contents Acumen Pharmaceuticals, Inc. Notes to Condensed Financial Statements (unaudited) As of June 30, 2026, all of the Company’s available-for-sale securities mature in less than one year . As noted in the table above, none of the Company’s available-for-sale marketable securities as of June 30, 2026 have been in an unrealized loss position for more than 12 months. As of December 31, 2025, some of the Company’s available-for-sale securities had been in an unrealized loss position for more than 12 months; however, the losses were immaterial . The Company does not intend to sell any of its available-for-sale 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 three and six months ended June 30, 2026 and 2025. The Company recorded immaterial realized gains during the six months ended June 30, 2026 and 2025. No realized gains were recorded during the three months ended June 30, 2026 and 2025. 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 as of June 30, 2026 using Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Fair Value at June 30, 2026 Assets included in: Cash and cash equivalents Money market securities $ 59,289 $ — $ — $ 59,289 Marketable securities Corporate debt securities — 28,942 — 28,942 Government and agency - U.S. — 21,812 — 21,812 Total fair value $ 59,289 $ 50,754 $ — $ 110,043 Liabilities included in: Debt, long-term Embedded derivatives liability $ — $ — $ 1,130 $ 1,130 Total fair value $ — $ — $ 1,130 $ 1,130 Fair value measurements as of December 31, 2025 using Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Fair Value at December 31, 2025 Assets included in: Cash and cash equivalents Money market securities $ 53,708 $ — $ — $ 53,708 Marketable securities Corporate debt securities — 62,876 — 62,876 Total fair value $ 53,708 $ 62,876 $ — $ 116,584 Liabilities included in: Debt, long-term Embedded derivatives liability $ — $ — $ 1,430 $ 1,430 Total fair value $ — $ — $ 1,430 $ 1,430 The carrying values reported in the Company’s condensed 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 13 Table of Contents Acumen Pharmaceuticals, Inc. Notes to Condensed Financial Statements (unaudited) expenses and other current liabilities are reasonable estimates of their fair values due to the short-term nature of these items. The carrying amount of the Company’s 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 debt, long-term. Certain features of the Company’s term loan facility (the “Term Loan”) were determined to be embedded derivatives requiring separate measurement from the loan host instrument. For additional information regarding the Term Loan, see Note 6. Debt . 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. The following table presents changes in Level 3 liabilities measured at fair value for the six months ended June 30, 2026 (in thousands): Balance, December 31, 2025 $ 1,430 Change in fair value of embedded derivatives ( 300 ) Balance, June 30, 2026 $ 1,130 NOTE 5. SUPPLEMENTAL FINANCIAL INFORMATION Prepaid expenses and other assets as of June 30, 2026 and December 31, 2025 consisted of the following (in thousands): June 30, 2026 Prepaid Expenses and Other Current Assets Other Assets, Long-Term Total Prepaid Expenses and Other Assets Research and development service agreements $ 3,763 $ 24 $ 3,787 Other receivables 1,005 — 1,005 Dues and subscriptions 246 — 246 Prepaid insurance 128 — 128 Property and equipment, net (1) — 80 80 Right-of-use asset — 72 72 Other 174 87 261 Total $ 5,316 $ 263 $ 5,579 14 Table of Contents Acumen Pharmaceuticals, Inc. Notes to Condensed Financial Statements (unaudited) December 31, 2025 Prepaid Expenses and Other Current Assets Other Assets, Long-Term Total Prepaid Expenses and Other Assets Research and development service agreements $ 3,527 $ 29 $ 3,556 Other receivables 625 — 625 Prepaid insurance 601 — 601 Dues and subscriptions 368 — 368 Right-of-use asset — 140 140 Property and equipment, net (1) — 103 103 Other 266 78 344 Total $ 5,387 $ 350 $ 5,737 (1) As of June 30, 2026 and December 31, 2025, accumulated depreciation totaled approximately $ 0.1 million and $ 0.2 million, respectively. Accrued expenses and other current liabilities as of June 30, 2026 consisted of the following (in thousands): Accrued Expenses and Other Current Liabilities Research and development 4,638 Compensation and other employee liabilities $ 2,409 Interest 241 Operating lease liability 77 Other 168 Total $ 7,533 Accrued expenses and other current liabilities as of December 31, 2025 consisted of the following (in thousands): Accrued Expenses and Other Current Liabilities Research and development $ 5,427 Compensation and other employee liabilities 4,066 Interest 249 Operating lease liability 150 Other 180 Total $ 10,072 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 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 principal amount of the Term Loan outstanding under the Loan Agreement bears interest per annum at the greater of (i) 9.65 % or (ii) the sum of the prime rate last quoted in The Wall Street Journal plus 1.15 % for such interest period. 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 15 Table of Contents Acumen Pharmaceuticals, Inc. Notes to Condensed Financial Statements (unaudited) $ 1.6 million (the “Final Payment”) due upon repayment of the Term Loan. As security for its obligations under the Loan Agreement, the Company granted the lenders a security interest in substantially all of the Company’s assets (other than intellectual property). 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 prepayment 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”) into the Company’s common stock at a conversion price of $ 2.53 (the “Conversion Option”). Prior to the consummation of the Company’s Private Placement (as defined below), which constituted the Next Qualified Financing (as defined in the Loan Agreement) pursuant to which the Company received aggregate gross proceeds of at least $ 20.0 million, the lenders also had an option to convert the Conversion Amount at a conversion price equal to 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 were 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. On March 13, 2026, the Company entered into a securities purchase agreement with certain institutional and accredited investors for a private placement (the “Private Placement”) of shares of the Company’s common stock. See additional information regarding the Private Placement in Note 7. Stockholders' Equity. The Private Placement was a Qualified Financing under the terms of the Loan Agreement and the lenders did not elect to convert the Conversion Amount at the time of the Private Placement. Therefore, the only remaining embedded derivative under the Loan Agreement is the Conversion Option (the “Embedded Derivative”) as the Share-Settled Redemption is no longer an election available to the lenders. 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 7. 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 at issuance of the Term Loan 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): June 30, 2026 December 31, 2025 Principal value of Term Loan, including Final Payment of $ 1,635 $ 31,635 $ 31,635 Fair value of bifurcated embedded derivatives 1,130 1,430 Unamortized debt discount ( 1,196 ) ( 1,904 ) Total 31,569 31,161 Less: debt, short-term 19,673 8,765 Total debt, long-term $ 11,896 $ 22,396 The following table provides the components of interest expense (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2026 2025 2026 2025 Interest expense based on the coupon interest rate of the outstanding debt $ 732 $ 732 $ 1,455 $ 1,456 Accretion of debt discount 362 314 708 613 Total interest expense related to debt $ 1,094 $ 1,046 $ 2,163 $ 2,069 16 Table of Contents Acumen Pharmaceuticals, Inc. Notes to Condensed Financial Statements (unaudited) For the three and six months ended June 30, 2026 the effective interest rate for the Term Loan was 14.8 % and 14.6 %, respectively. For the three and six months ended June 30, 2025 the effective interest rate for the Term Loan was 14.1 % and 14.0 %, respectively. As of June 30, 2026, the aggregate principal payments due for the Term Loan by year are as follows (in thousands): Year ended December 31, 2026 $ 10,104 Year ended December 31, 2027 21,531 Total principal payments due for Term Loan $ 31,635 NOTE 7. STOCKHOLDERS’ EQUITY Authorized Shares As of June 30, 2026, 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 per share, and 300,000,000 shares designated as common stock with a par value of $ 0.0001 per share. Each share of common stock issued and outstanding is entitled to one vote. Private Placement On March 13, 2026, the Company entered into the Private Placement of 10,833,331 shares of the Company’s common stock, at an offering price of $ 3.30 per share. The Private Placement closed on March 16, 2026, for aggregate gross proceeds of approximately $ 35.7 million, before deducting offering costs of approximately $ 0.3 million. The Company intends to use the net proceeds from the Private Placement to primarily support its EBD program, including ongoing preclinical development work to support the nomination of a lead clinical candidate molecule, and for working capital and other general corporate purposes. The Company filed a shelf registration statement on Form S-3 with the Securities and Exchange Commission on March 26, 2026 to register the shares sold in the Private Placement. Shelf Registration and At The Market Equity Offering On July 1, 2022, the Company filed a shelf registration statement on Form S-3 (the “2022 Registration Statement”). Pursuant to the 2022 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 2022 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 was included in the $ 200.0 million of securities that were registered for sale pursuant to the 2022 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, BofA and Stifel are collectively referred to as 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 the Company’s common stock made under the ATM. The Company is not obligated to make any sales of shares of its common stock under the ATM. During the six months ended June 30, 2026 and 2025, the Company did not sell any shares of common stock under the ATM. The Company has issued shares of common stock for aggregate gross proceeds of $ 12.2 million under the ATM since the program’s inception. On March 27, 2024, the Company filed a shelf registration statement on Form S-3 (the “2024 Registration Statement”). Pursuant to the 2024 Registration Statement, the Company may offer and sell securities having an aggregate public offering price of up to $ 200.0 million. On November 13, 2025, the Company filed a prospectus supplement to the 2024 Registration Statement with respect to its ATM, designating up to $ 50.0 million of the $ 200.0 million of securities that may be offered pursuant to the 2024 Registration Statement for issuance under the ATM. 17 Table of Contents Acumen Pharmaceuticals, Inc. Notes to Condensed Financial Statements (unaudited) Restricted Stock Units During the six months ended June 30, 2026 and 2025, the Company issued 791,052 and 446,756 shares, respectively, of its common stock in settlement of fully vested RSUs. 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 its 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 equity-classified warrant is outstanding as of June 30, 2026. NOTE 8. 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, RSUs, 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 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 terms of the 2013 Plan. As of June 30, 2026, there were 3,028,936 options outstanding under the 2013 Plan. On June 3, 2026, Acumen’s stockholders approved the adoption of the Company’s Amended and Restated 2021 Equity Incentive Plan (the “Amended and Restated 2021 Plan”) to (i) increase the number of shares available for issuance by 10,000,000 shares, (ii) remove the automatic “evergreen” share pool increase provision, and (iii) prohibit repricing of stock options without stockholder approval (other than in connection with certain corporate transactions). Prior to the effectiveness of the Amended and Restated 2021 Plan, the number of shares of common stock reserved for issuance under the 2021 Plan automatically increased on January 1 of each calendar year, 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 of directors prior to the applicable January 1. On January 1, 2026, the number of shares of common stock reserved for issuance under the 2021 Plan automatically increased by 3,028,768 shares. The maximum number of shares of common stock that may be issued upon the exercise of incentive stock options under the Amended and Restated 2021 Plan is 29,040,630 . As of June 30, 2026, a total of 30,702,193 shares were authorized for issuance under the Amended and Restated 2021 Plan and 10,453,627 shares remained available for issuance under the Amended and Restated 2021 Plan. The Company recorded stock-based compensation expense related to stock options and RSUs in the following expense categories of its condensed statements of operations and comprehensive loss for the periods shown (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2026 2025 2026 2025 General and administrative $ 1,462 $ 1,491 $ 2,828 $ 2,983 Research and development 1,062 1,007 2,092 1,989 Total stock-based compensation $ 2,524 $ 2,498 $ 4,920 $ 4,972 18 Table of Contents Acumen Pharmaceuticals, Inc. Notes to Condensed Financial Statements (unaudited) Stock Options The Black-Scholes option-pricing model was used to estimate the fair value of stock options granted during the six months ended June 30, 2026 and 2025 with the following weighted average assumptions: Six Months Ended June 30, 2026 2025 Risk-free interest rate 3.70 % - 4.34 % 3.93 % - 4.52 % Expected term (in years) 1.0 - 6.0 1.0 - 6.0 Expected volatility 84 % - 90 % 76 % - 92 % Expected dividend yield 0 % 0 % The weighted average grant date fair value of options granted during the six months ended June 30, 2026 and 2025 was $ 1.47 per share and $ 1.26 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 10-year contractual term. Beginning January 1, 2024, stock options granted to consultants vest quarterly over a one-year period, provided that such consultants continue to perform services as dictated by their respective consulting agreements with the Company. Annual option awards issued to members of the Company’s board of directors 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 also have a 10-year term. The Company’s common stock became publicly traded in July 2021. Prior to January 1, 2025, the Company lacked sufficient company-specific historical and implied volatility information for its common stock and estimated 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. Beginning on January 1, 2025, based on the availability of sufficient historical trading data of the Company’s common stock, the Company began using its historical volatility to estimate expected stock 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 during the six months ended June 30, 2026: Stock Options Weighted Average Exercise Price Weighted Average Remaining Contractual Life (in years) Aggregate Intrinsic Value (in thousands) Outstanding as of December 31, 2025 12,578,766 $ 3.46 Granted 3,135,539 $ 1.97 Exercised ( 114,962 ) $ 1.50 Forfeited ( 65,286 ) $ 2.11 Expired ( 92,959 ) $ 2.32 Outstanding as of June 30, 2026 15,441,098 $ 3.18 7.1 $ 362 Vested and exercisable as of June 30, 2026 9,634,417 $ 3.61 6.0 $ 351 The intrinsic value of stock options exercised during the six months ended June 30, 2026 was approximately $ 0.1 million and the intrinsic value of stock options exercised during the six months ended June 30, 2025 was immaterial . As of June 30, 2026, total unrecognized compensation costs related to unvested stock option awards were approximately $ 10.7 million, which the Company expects to recognize over a weighted-average period of approximately 2.3 years. 19 Table of Contents Acumen Pharmaceuticals, Inc. Notes to Condensed Financial Statements (unaudited) Restricted Stock Units RSUs granted to employees vest in equal annual installments on the first three anniversaries of the grant date and RSUs granted to members of the Company’s board of directors vest in full on the first anniversary of the grant date. The following table reflects summarized RSU activity during the six months ended June 30, 2026: Number of Shares Weighted Average Grant Date Fair Value Unvested as of December 31, 2025 1,907,976 $ 2.93 Granted 2,045,683 $ 1.97 Vested ( 869,203 ) $ 3.28 Forfeited ( 25,685 ) $ 1.93 Unvested as of June 30, 2026 3,058,771 $ 2.20 As of June 30, 2026, total unrecognized compensation costs related to unvested RSUs were approximately $ 5.1 million, which the Company expects to recognize over a weighted-average period of approximately 1.9 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, however, that before the date of any such increase, the board of directors may determine that such increase will be less than the amount set forth in clauses (1) and (2). On January 1, 2026, the number of shares of common stock reserved for issuance under the ESPP automatically increased by 605,754 shares. As of June 30, 2026, there are a total of 2,975,783 shares reserved for issuance under the ESPP and there have been no purchases of shares under the ESPP, as the ESPP has not yet been implemented. NOTE 9. SEGMENT REPORTING The Company manages its operations as a single reportable segment which includes research and development efforts for the treatment of AD. The CODM assesses performance and allocates resources for the segment based on segment net loss, which is reported on the statement of operations and comprehensive loss as net loss. The CODM uses segment net loss to monitor spending, assess performance for the Company and management, evaluate the progress of completing corporate goals and make decisions regarding the allocation of resources. Substantially all long-lived assets are located in the United States. The measure of segment assets is reported on the balance sheet as total assets. 20 Table of Contents Acumen Pharmaceuticals, Inc. Notes to Condensed Financial Statements (unaudited) The following table presents selected financial information about the Company’s single operating segment for the three and six months ended June 30, 2026 and 2025 (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2026 2025 2026 2025 Operating expenses Research and development External costs $ 22,418 $ 31,559 $ 33,177 $ 50,986 Internally managed costs (1) 4,329 4,556 9,024 9,409 General and administrative (2) 3,274 3,121 6,561 6,722 Other segment expenses (3) 2,535 2,514 4,943 5,003 Other expense (income), net 162 ( 800 ) ( 250 ) ( 2,374 ) Segment net loss $ 32,718 $ 40,950 $ 53,455 $ 69,746 (1) Includes Company-managed research, consultants and contractors, as well as internal personnel and operating expenses, and excludes stock-based compensation expense and depreciation. (2) Excludes stock-based compensation expense and depreciation. (3) Other segment expenses include stock-based compensation expense and depreciation. NOTE 10. 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 July 2025, the Company entered into a collaboration, option and license agreement with JCR to develop an Aß oligomer-targeted EBD ™ therapy for the treatment of AD. Under the terms of the agreement, the Company paid JCR an upfront license payment, which was recognized as in-process research and development expense during the year ended December 31, 2025. In June 2026, the Company nominated two EBD development candidates for the treatment of AD pursuant to its collaboration agreement with JCR and exercised its exclusive option to license and develop such development candidates. The option exercise payment of $ 9.25 million was recognized as in-process research and development expense during the three and six months ended June 30, 2026 and was paid to JCR in July 2026. JCR will also be eligible to receive future milestone payments of up to $ 40.0 million related to development, and up to $ 515.0 million related to sales, for a total of up to $ 555.0 million, as well as single-digit percentage royalties on sales of any products that emerge from the collaboration. 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”). In January 2024, the Company paid a seven-figure upfront license payment for the Halozyme Product. The Company is required to make milestone payments upon the achievement of certain development and commercialization 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. The upfront license payment and milestones are recorded as in-process research and development expense when incurred. In November 2022, the Company entered into a License Agreement (the “Lonza License Agreement”) with Lonza Sales AG (“Lonza”). Under the terms of the Lonza License Agreement, Lonza granted the Company a worldwide non-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 figures and a royalty of less 21 Table of Contents Acumen Pharmaceuticals, Inc. Notes to Condensed Financial Statements (unaudited) than 1 % on net sales where the Company manufactures the Lonza Product and (iii) an annual payment in Swiss Francs in the mid-six figures per sublicense and a royalty on net sales in the low single digits where a third party manufactures the Lonza Product. These payment obligations expire ten years from the first commercial sales of the Lonza Product in such country of sale. 22 Table of Contents