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10-Q – 2026-07-30 – alny-20260630.htm
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(Exact Name of Registrant as Specified in Its Charter) __________________________________________ Delaware (State or Other Jurisdiction of Incorporation or Organization) 77-0602661 (I.R.S. Employer Identification No.) 675 West Kendall Street, Henri A. Termeer Square Cambridge , MA (Address of Principal Executive Offices) 02142 (Zip Code) ( 617 ) 551-8200 (Registrant’s Telephone Number, Including Area Code) __________________________________________ Securities registered pursuant to Section 12(b) of the Act: Title of Each Class Trading Symbol(s) Name of Each Exchange on Which Registered Common Stock, $0.01 par value per share ALNY The Nasdaq Stock Market LLC Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes x No ☐ Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes x No ☐ Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act. Large accelerated filer x Accelerated filer ☐ Non-accelerated filer ☐ Smaller reporting company ☐ Emerging growth company ☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐ Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes ☐ No x At July 24, 2026, the registrant had 133,809,118 shares of Common Stock, $0.01 par value per share, outstanding. ALNYLAM PHARMACEUTICALS, INC. QUARTERLY REPORT ON FORM 10-Q TABLE OF CONTENTS PAGE NUMBER PART I. FINANCIAL INFORMATION ITEM 1. FINANCIAL STATEMENTS (UNAUDITED) CONDENSED CONSOLIDATED BALANCE SHEETS AS OF JUNE 30 , 2026 AND DECEMBER 31, 2025 5 CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME (LOSS) FOR THE THREE AND SIX MONTHS ENDED JUNE 30 , 2026 AND 2025 6 CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY FOR THE THREE MONTHS ENDED JUNE 30 , 2026 AND 2025 AND THE THREE MONTHS ENDED MARCH 31, 2026 AND 2025 7 CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS FOR THE SIX MONTHS ENDED JUNE 30 , 2026 AND 2025 9 NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS 10 ITEM 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS 30 ITEM 3. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK 42 ITEM 4. CONTROLS AND PROCEDURES 42 PART II. OTHER INFORMATION ITEM 1. LEGAL PROCEEDINGS 44 ITEM 1A. RISK FACTORS 44 ITEM 5. OTHER INFORMATION 82 ITEM 6. EXHIBITS 82 SIGNATURES 83 “Alnylam,” AMVUTTRA ® , ONPATTRO ® , GIVLAARI ®, OXLUMO ® and siRELIS TM are registered trademarks of Alnylam Pharmaceuticals, Inc. Our logo, trademarks and service marks are property of Alnylam. All other trademarks or service marks appearing in this Quarterly Report on Form 10-Q are the property of their respective holders. 2 Table of Contents CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS This Quarterly Report on Form 10-Q contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. We intend these forward-looking statements to be covered by the safe harbor provisions for forward-looking statements contained in the Private Securities Litigation Reform Act of 1995 and are including this statement for purposes of complying with those safe harbor provisions. All statements other than statements of historical fact contained in this Quarterly Report on Form 10-Q are forward-looking statements. In some cases, you can identify forward-looking statements by terminology such as “may,” “will,” “should,” “could,” “expects,” “plans,” “intends,” “aspires,” “anticipates,” “believes,” “estimates,” “predicts,” “potential,” “continue,” or the negative of these terms or other comparable terminology. These forward-looking statements include, but are not limited to, statements about: • our expectations regarding future revenues, expenses, margins, profitability, cash flows, capital expenditures, and other aspects of our financial performance, as well as our financial guidance and outlook for upcoming periods; • our ability to successfully execute on our “ Alnylam 2030 ” strategy and our aspiration to achieve the metrics associated with this strategy; • our views with respect to the clinical and commercial potential of (including the potential numbers of patients who may benefit from) our approved and investigational RNAi therapeutics and those of our collaborators, including AMVUTTRA, ONPATTRO, GIVLAARI, OXLUMO, Leqvio® (inclisiran), Qfitlia ® (fitusiran), zilebesiran, mivelsiran, nucresiran and cemdisiran; • our plans for additional global regulatory filings and the continuing product launches of AMVUTTRA, ONPATTRO, GIVLAARI, OXLUMO and our collaborators’ plans with respect to Leqvio, Qfitlia and cemdisiran; • our ability to obtain regulatory approval of AMVUTTRA (vutrisiran) for the treatment of ATTR amyloidosis with cardiomyopathy in additional jurisdictions outside the United States; • our expectations regarding the potential market size for, and the successful commercialization of, AMVUTTRA, ONPATTRO, GIVLAARI, OXLUMO, Leqvio, Qfitlia or any future products; • our ability to obtain and maintain regulatory approvals and pricing, reimbursement and patient access and insurance coverage for AMVUTTRA, ONPATTRO, GIVLAARI, OXLUMO or any future products, and our collaborators’ ability with respect to Leqvio, Qfitlia and cemdisiran; • the progress of our research and development programs, including programs across a broad range of disease areas and indications; • the potential for improved product profiles to emerge from our technologies and our ability to expand our clinical development pipeline to include additional tissue types and disease indications; • our current and anticipated clinical trials and expectations regarding the reporting of data from these trials; • the number and timing of regulatory filings and interactions with, or actions or advice of, regulatory authorities, which may affect the design, initiation, timing, continuation and/or progress of clinical trials, or result in the need for additional preclinical and/or clinical testing or the timing or likelihood of regulatory approvals; • the status of our manufacturing operations and any delays, interruptions or failures in the manufacture and supply of AMVUTTRA, ONPATTRO, GIVLAARI, OXLUMO or any of our product candidates (or Leqvio, Qfitlia, cemdisiran or other products or product candidates being developed and commercialized by our collaborators), by our or their contract manufacturers or by us or our collaborators; • the impact of current and potential healthcare reforms, including those affecting the delivery, pricing or government price reporting of or payment, insurance coverage or reimbursement for, healthcare products and services; • the impact of any future pandemics or public health emergencies on, among other things, our financial performance, business and operations, including manufacturing, supply chain, research and development activities and pipeline programs, and other potential impacts to our business; • our progress continuing to build and leverage our global commercial infrastructure; 3 Table of Contents • the possible impact of any competing products, including generic versions of competing products, on the commercial success of AMVUTTRA, ONPATTRO, GIVLAARI, OXLUMO, Leqvio and Qfitlia, as well as our product candidates, and our, or with respect to Leqvio or Qfitlia, our collaborators’, ability to compete against such products; • our ability to manage our growth and operating expenses; • our expectations regarding the length of time our current cash, cash equivalents and marketable debt securities will support our operations based on our current operating plan; • the ability of the third parties on which we rely for development, manufacture and distribution of our products to meet their obligations to us; • our ability to maintain our existing collaborations and our expectations regarding potential future research and development funding, licensing fees and milestone and royalty payments that we may receive under existing or future collaboration agreements; • our ability to obtain, maintain and protect our intellectual property; • our ability to attract and retain qualified key management and scientists, development, medical and commercial staff, consultants and advisors; • the outcome of litigation or other legal proceedings or government investigations; • regulatory developments in the U.S. and other jurisdictions; • the impact of laws and regulations; • developments relating to our competitors and our industry; • our ability to satisfy our payment obligations, and to service the interest on, or to refinance our indebtedness, including our convertible notes, or to make cash payments in connection with any conversion of our convertible notes, to the extent required; and • our expectations regarding the effect of the capped call transactions and the anticipated market activities of the option counterparties and/or their respective affiliates. Any forward-looking statements in this Quarterly Report on Form 10-Q reflect our current views with respect to future events and with respect to our business and future financial performance, and involve known and unknown risks, uncertainties and other factors that may cause our actual results, performance or achievements to be materially different from any future results, performance or achievements expressed or implied by these forward-looking statements. Factors that may cause actual results to differ materially from current expectations include, among other things, those described under Part II, Item 1A, “Risk Factors” and elsewhere in this Quarterly Report on Form 10-Q. Moreover, we operate in a very competitive and rapidly changing environment. New risk factors emerge from time to time and it is not possible for management to predict all risk factors, nor can we assess the impact of all risk factors on our business or the extent to which any factor, or combination of factors, may cause actual results to differ materially from those contained in any forward-looking statements. Given these uncertainties, you should not place undue reliance on these forward-looking statements. Except as required by law, we assume no obligation to update or revise these forward-looking statements for any reason, even if new information becomes available in the future. You are advised, however, to consult any further disclosure we make in our reports filed with the Securities and Exchange Commission, or SEC. This Quarterly Report on Form 10-Q may include data that we obtained from industry publications and third-party research, surveys and studies. Industry publications and third-party research, surveys and studies generally indicate that their information has been obtained from sources believed to be reliable, although they do not guarantee the accuracy or completeness of such information. This Quarterly Report on Form 10-Q also may include data based on our own internal estimates and research, which have not been verified by any independent source and, while we believe any data obtained from industry publications and third-party research, surveys and studies are reliable, we have not independently verified such data. Any such third-party data, as well as our internal estimates and research, are subject to a high degree of uncertainty and risk due to a variety of factors, including those described in Part II, Item 1A, “Risk Factors” and elsewhere in this Quarterly Report on Form 10-Q. These and other factors could cause our results to differ materially from those expressed in this Quarterly Report on Form 10-Q. 4 Table of Contents PART I. FINANCIAL INFORMATION ITEM 1. FINANCIAL STATEMENTS ( UNAUDITED ) ALNYLAM PHARMACEUTICALS, INC. CONDENSED CONSOLIDATED BALANCE SHEETS (In thousands, except per share amounts) (Unaudited) June 30, 2026 December 31, 2025 ASSETS Current assets: Cash and cash equivalents $ 1,708,318 $ 1,657,250 Marketable debt securities 1,599,829 1,251,234 Accounts receivable, net 912,739 777,567 Inventory 97,110 82,719 Prepaid expenses and other current assets 302,176 281,892 Total current assets 4,620,172 4,050,662 Property, plant and equipment, net 554,143 513,147 Operating lease right-of-use assets 183,359 194,916 Deferred tax assets 113,792 125,975 Restricted investments 22,171 22,170 Other assets 65,132 59,461 Total assets $ 5,558,769 $ 4,966,331 LIABILITIES AND STOCKHOLDERS' EQUITY Current liabilities: Accounts payable $ 108,016 $ 115,721 Accrued expenses 1,095,980 1,080,197 Operating lease liabilities 45,933 45,518 Deferred revenue 4,014 4,845 Liabilities related to the sale of future royalties and development funding 258,570 220,068 Total current liabilities 1,512,513 1,466,349 Operating lease liabilities, net of current portion 210,495 225,087 Convertible debt 1,010,981 1,007,784 Liabilities related to the sale of future royalties and development funding, net of current portion 1,461,510 1,470,341 Other liabilities 9,152 7,594 Total liabilities 4,204,651 4,177,155 Commitments and contingencies (Note 12) Stockholders' equity: Preferred stock, $ 0.01 par value per share, 5,000 shares authorized and no shares issued and outstanding as of June 30, 2026 and December 31, 2025 — — Common stock, $ 0.01 par value per share, 250,000 shares authorized; 133,734 shares issued and outstanding as of June 30, 2026; 132,376 shares issued and outstanding as of December 31, 2025 1,337 1,324 Additional paid-in capital 7,716,958 7,510,473 Accumulated other comprehensive loss ( 32,138 ) ( 20,097 ) Accumulated deficit ( 6,332,039 ) ( 6,702,524 ) Total stockholders' equity 1,354,118 789,176 Total liabilities and stockholders' equity $ 5,558,769 $ 4,966,331 The accompanying notes are an integral part of these condensed consolidated financial statements. 5 Table of Contents ALNYLAM PHARMACEUTICALS, INC. CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME (LOSS) (In thousands, except per share amounts) (Unaudited) Three Months Ended June 30, Six Months Ended June 30, 2026 2025 2026 2025 Statements of Operations Revenues: Net product revenues $ 1,172,109 $ 672,212 $ 2,208,236 $ 1,140,750 Net revenues from collaborations 47,165 61,496 129,240 160,681 Royalty revenue 71,674 39,981 120,647 66,447 Total revenues 1,290,948 773,689 2,458,123 1,367,878 Operating costs and expenses: Cost of goods sold 298,261 142,029 505,781 212,212 Cost of collaborations and royalties 190 924 3,792 1,782 Research and development 413,134 323,621 778,000 588,743 Selling, general and administrative 347,922 323,314 670,473 563,263 Total operating costs and expenses 1,059,507 789,888 1,958,046 1,366,000 Income (loss) from operations 231,441 ( 16,199 ) 500,077 1,878 Other (expense) income: Interest expense ( 82,051 ) ( 61,456 ) ( 151,337 ) ( 119,765 ) Interest income 28,143 27,486 54,741 56,159 Other income (expense), net 273 8,860 ( 4,022 ) 18,051 Total other expense, net ( 53,635 ) ( 25,110 ) ( 100,618 ) ( 45,555 ) Income (loss) before income taxes 177,806 ( 41,309 ) 399,459 ( 43,677 ) Provision for income taxes ( 13,312 ) ( 30,919 ) ( 28,974 ) ( 46,802 ) Net income (loss) $ 164,494 $ ( 72,228 ) $ 370,485 $ ( 90,479 ) Net income (loss) per common share — basic $ 1.23 $ ( 0.55 ) $ 2.78 $ ( 0.70 ) Net income (loss) per common share — diluted $ 1.21 $ ( 0.55 ) $ 2.71 $ ( 0.70 ) Weighted-average common shares — basic 133,606 130,628 133,244 130,155 Weighted-average common shares — diluted 138,281 130,628 138,249 130,155 Statements of Comprehensive Income (Loss) Net income (loss) $ 164,494 $ ( 72,228 ) $ 370,485 $ ( 90,479 ) Other comprehensive (loss) income: Unrealized (losses) gains on marketable securities ( 3,635 ) ( 343 ) ( 7,287 ) 687 Foreign currency translation (losses) gains ( 3,698 ) 7,855 ( 4,932 ) 3,771 Defined benefit pension plans, net of tax 89 53 178 108 Total other comprehensive (loss) income ( 7,244 ) 7,565 ( 12,041 ) 4,566 Comprehensive income (loss) $ 157,250 $ ( 64,663 ) $ 358,444 $ ( 85,913 ) The accompanying notes are an integral part of these condensed consolidated financial statements. 6 Table of Contents ALNYLAM PHARMACEUTICALS, INC. CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY (In thousands) (Unaudited) Common Stock Additional Paid-in Capital Accumulated Other Comprehensive Loss Accumulated Deficit Total Stockholders' Equity Shares Amount Balance as of December 31, 2025 132,376 $ 1,324 $ 7,510,473 $ ( 20,097 ) $ ( 6,702,524 ) $ 789,176 Exercise of common stock options, net of tax withholdings 102 1 13,750 — — 13,751 Issuance of common stock under equity plans 966 9 ( 9 ) — — — Stock-based compensation — — 71,259 — — 71,259 Other comprehensive loss — — — ( 4,797 ) — ( 4,797 ) Net income — — — — 205,991 205,991 Balance as of March 31, 2026 133,444 $ 1,334 $ 7,595,473 $ ( 24,894 ) $ ( 6,496,533 ) $ 1,075,380 Exercise of common stock options, net of tax withholdings 182 2 33,756 — — 33,758 Issuance of common stock under equity plans 108 1 ( 1 ) — — — Stock-based compensation — — 87,730 — — 87,730 Other comprehensive loss — — — ( 7,244 ) — ( 7,244 ) Net income — — — — 164,494 164,494 Balance as of June 30, 2026 133,734 1,337 7,716,958 ( 32,138 ) ( 6,332,039 ) 1,354,118 7 Table of Contents ALNYLAM PHARMACEUTICALS, INC. CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY (In thousands) (Unaudited) Common Stock Additional Paid-in Capital Accumulated Other Comprehensive Loss Accumulated Deficit Total Stockholders’ Equity Shares Amount Balance as of December 31, 2024 129,294 $ 1,293 $ 7,388,061 $ ( 34,518 ) $ ( 7,287,748 ) $ 67,088 Cumulative effect adjustment from adoption of ASU 2025-07 — — — — 271,477 271,477 Exercise of common stock options, net of tax withholdings 423 4 50,981 — — 50,985 Issuance of common stock under equity plans 594 6 ( 6 ) — — — Stock-based compensation — — 57,840 — — 57,840 Other comprehensive loss — — — ( 2,999 ) — ( 2,999 ) Net loss — — — — ( 18,251 ) ( 18,251 ) Balance as of March 31, 2025 130,311 $ 1,303 $ 7,496,876 $ ( 37,517 ) $ ( 7,034,522 ) $ 426,140 Exercise of common stock options, net of tax withholdings 556 6 81,055 — — 81,061 Issuance of common stock under equity plans 110 1 ( 1 ) — — — Stock-based compensation — — 112,807 — — 112,807 Other comprehensive income — — — 7,565 — 7,565 Net loss — — — — ( 72,228 ) ( 72,228 ) Balance as of June 30, 2025 130,977 1,310 7,690,737 ( 29,952 ) ( 7,106,750 ) 555,345 The accompanying notes are an integral part of these condensed consolidated financial statements. 8 Table of Contents ALNYLAM PHARMACEUTICALS, INC. CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (In thousands) (Unaudited) Six Months Ended June 30, 2026 2025 Cash flows from operating activities: Net income (loss) $ 370,485 $ ( 90,479 ) Adjustments to reconcile net income (loss) to net cash provided by operating activities: Depreciation and amortization 27,452 28,349 Non-cash interest expense on liabilities related to the sale of future royalties and development funding 145,279 112,307 Stock-based compensation expense 156,779 168,392 Realized and unrealized loss on marketable equity securities — 2,306 Deferred income taxes 11,967 19,374 Other 11,272 ( 37,864 ) Changes in operating assets and liabilities: Accounts receivable, net ( 142,023 ) ( 144,347 ) Inventory ( 3,044 ) 17,359 Prepaid expenses and other assets ( 65,692 ) ( 25,992 ) Accounts payable, accrued expenses and other liabilities ( 114,416 ) 490 Deferred revenue ( 831 ) ( 40,400 ) Net cash provided by operating activities 397,228 9,495 Cash flows from investing activities: Purchases of property, plant and equipment ( 56,513 ) ( 23,263 ) Purchases of marketable securities ( 837,297 ) ( 861,199 ) Sales and maturities of marketable securities 485,986 856,850 Proceeds from maturity of restricted and other investments 66,725 58,075 Purchases of restricted and other investments ( 22,000 ) ( 58,075 ) Other investing activities ( 25,900 ) — Net cash used in investing activities ( 388,999 ) ( 27,612 ) Cash flows from financing activities: Proceeds from exercise of stock options and other types of equity, net 46,718 130,587 Proceeds from liabilities related to the sale of future royalties and development funding 12,000 — Repayment of liabilities related to the sale of future royalties and development funding ( 6,752 ) ( 6,825 ) Other financing activities ( 15 ) — Net cash provided by financing activities 51,951 123,762 Effect of exchange rate changes on cash, cash equivalents and restricted cash ( 9,509 ) 41,564 Net increase in cash, cash equivalents and restricted cash 50,671 147,209 Cash, cash equivalents and restricted cash, beginning of period 1,658,807 968,652 Cash, cash equivalents and restricted cash, end of period $ 1,709,478 $ 1,115,861 Supplemental disclosure of cash flows: Cash paid for interest $ 122,314 $ 107,418 Cash paid for taxes $ 14,734 $ 1,098 Operating lease right-of-use assets obtained in exchange for new operating lease liabilities $ — $ 8,537 Supplemental disclosure of noncash investing activities: Capital expenditures included in accounts payable and accrued expenses $ 24,032 $ 4,081 The accompanying notes are an integral part of these condensed consolidated financial statements. 9 Table of Contents ALNYLAM PHARMACEUTICALS, INC. NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Unaudited) 1. NATURE OF BUSINESS Alnylam Pharmaceuticals, Inc. (also referred to as Alnylam, the Company, we, our or us) commenced operations on June 14, 2002 as a biopharmaceutical company seeking to develop and commercialize novel therapeutics based on ribonucleic acid interference, or RNAi. We are committed to the advancement of our company strategy of building a multi-product, global, commercial biopharmaceutical company with a deep and sustainable clinical pipeline of RNAi therapeutics for future growth and a robust, organic research engine for sustainable innovation and great potential for patient impact. Since inception, we have focused on discovering, developing and commercializing RNAi therapeutics by establishing and maintaining a strong intellectual property position in the RNAi field, establishing strategic collaborations with leading pharmaceutical and life sciences companies, generating revenues through licensing agreements, and ultimately developing and commercializing RNAi therapeutics globally, either independently or with our strategic collaborators. We have devoted substantially all of our efforts to business planning, research, development, manufacturing and commercializing biopharmaceutical products, acquiring, filing and expanding our intellectual property rights, recruiting our management and technical staff, and raising capital. As of June 30, 2026, we have six marketed products, including two products that are commercialized by collaborators, and multiple late-stage investigational programs advancing towards potential commercialization. We currently generate worldwide product revenues from four commercialized products, AMVUTTRA, ONPATTRO, GIVLAARI and OXLUMO, primarily in the United States, or U.S., and Europe. 2. BASIS OF PRESENTATION AND PRINCIPLES OF CONSOLIDATION The accompanying condensed consolidated financial statements of Alnylam are unaudited and have been prepared in accordance with accounting principles generally accepted in the United States of America, or GAAP, applicable to interim periods and, in the opinion of management, include all normal and recurring adjustments that are necessary to state fairly the results of operations for the reported periods. Our condensed consolidated financial statements have also been prepared on a basis substantially consistent with, and should be read in conjunction with, our audited consolidated financial statements for the year ended December 31, 2025, which were included in our Annual Report on Form 10-K that was filed with the Securities and Exchange Commission on February 12, 2026. The year-end condensed consolidated balance sheet data was derived from our audited financial statements but does not include all disclosures required by GAAP. The results of our operations for any interim period are not necessarily indicative of the results of our operations for any other interim period or for a full fiscal year. The accompanying condensed consolidated financial statements reflect the operations of Alnylam and our wholly-owned subsidiaries. All intercompany accounts and transactions have been eliminated. We evaluate variable interests in a variable interest entity, or VIE, and consolidate VIEs when we are the primary beneficiary. Determination of whether we are the primary beneficiary of each VIE is based on an assessment of whether we possess both (i) the power to direct the activities that most significantly affect the VIE’s economic performance and (ii) the obligation to absorb losses or the right to receive benefits that could be significant to the VIE. We continuously reevaluate the accounting for our VIEs upon the occurrence of events that could change the primary beneficiary conclusion. The maximum risk of loss related to our VIEs is generally limited to the carrying value of the investment in such entities, but may also include prepaid expenses recognized for advances made to a VIE and future funding commitments, if applicable. Certain prior period amounts in the condensed consolidated financial statements have been retrospectively adjusted to reflect the guidance of Accounting Standards Update, or ASU, 2025-07, Derivatives Scope Refinements and Scope Clarification for Share-Based Noncash Consideration from a Customer in a Revenue Contract , which we adopted in the fourth quarter of 2025 on a modified retrospective basis as of January 1, 2025. Refer to Note 2 of the Notes to Consolidated Financial Statements included in our Annual Report on Form 10-K for the year ended December 31, 2025. Our significant accounting policies are described in Note 2 of the Notes to Consolidated Financial Statements included in our Annual Report on Form 10-K for the year ended December 31, 2025. There have been no material changes to our significant accounting policies during the six months ended June 30, 2026. Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities as of the date of the condensed consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. In our condensed consolidated financial statements, we use estimates and assumptions related to our inventory valuation and related reserves, clinical accruals, liabilities related to the sale of future royalties and development funding, income taxes, deferred tax asset valuation allowances, revenue recognition and related allowances and reserves, research and development expenses, and stock-based compensation expense. We base our estimates on historical experience and on various other 10 Table of Contents ALNYLAM PHARMACEUTICALS, INC. NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Unaudited) assumptions that we believe to be reasonable. Actual results could differ from those estimates. Changes in estimates are reflected in reported results in the period in which they become known. Liquidity Based on our current operating plan, we believe that our cash, cash equivalents, marketable securities, as well as the revenue we expect to generate from product sales and under our existing collaborations, including royalties on sales of Leqvio and Qfitlia, and available borrowing capacity under the revolving credit agreement, or the Revolving Credit Agreement, as of June 30, 2026, will be sufficient to satisfy our near-term capital and operating needs for at least the next 12 months from the filing date of this Quarterly Report on Form 10-Q. Please refer to Note 8, Convertible Debt and Other Financing, for further information related to the Revolving Credit Agreement. Recent Accounting Pronouncements In September 2025, the Financial Accounting Standards Board, or FASB, issued ASU 2025-06, Targeted Improvements to the Accounting for Internal-Use Software , which modernizes the guidance for internal-use software costs by increasing the operability of the recognition guidance considering different methods of software development. The standard will be effective for annual reporting periods beginning after December 15, 2027, as well as interim period reporting periods within those annual reporting periods, with early adoption permitted. The standard updates may be applied on a prospective, retrospective, or modified retrospective approach. We are currently evaluating the impact this guidance could have on our condensed consolidated financial statements and related disclosures. In November 2024, the FASB issued ASU 2024-03, Disaggregation of Income Statement Expenses , or ASU 2024-03, which is intended to improve disclosures by requiring additional information about specific expense categories in the notes to the financial statements on an annual and interim basis. Additionally, in January 2025, the FASB issued ASU 2025-01, clarifying that ASU 2024-03 will be effective for annual reporting periods beginning after December 15, 2026 and interim reporting periods beginning after December 15, 2027, with early adoption permitted. The standard updates may be applied on either a prospective or retrospective basis. We are currently evaluating the disclosure requirements related to ASU 2024-03. 11 Table of Contents ALNYLAM PHARMACEUTICALS, INC. NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Unaudited) 3. NET PRODUCT REVENUES Net product revenues, classified based on the geographic region in which the product is sold and by franchise (“TTR,” which includes AMVUTTRA and ONPATTRO, and “Rare,” which includes GIVLAARI and OXLUMO) consisted of the following: Three Months Ended June 30, Six Months Ended June 30, (In thousands) 2026 2025 2026 2025 AMVUTTRA United States $ 809,079 $ 361,346 $ 1,511,633 $ 559,310 Europe 119,010 92,868 232,323 172,956 Rest of World 83,673 37,739 157,737 69,679 Total 1,011,762 491,953 1,901,693 801,945 ONPATTRO United States 9,863 22,053 20,029 37,625 Europe 5,508 21,246 13,073 47,787 Rest of World 3,090 9,239 5,840 16,615 Total 18,461 52,538 38,942 102,027 Total TTR 1,030,223 544,491 1,940,635 903,972 GIVLAARI United States 58,000 55,151 107,091 98,945 Europe 24,323 20,966 44,613 39,510 Rest of World 7,441 4,732 12,454 9,362 Total 89,764 80,849 164,158 147,817 OXLUMO United States 18,545 16,019 35,510 30,128 Europe 22,678 21,929 47,068 42,913 Rest of World 10,899 8,924 20,865 15,920 Total 52,122 46,872 103,443 88,961 Total Rare 141,886 127,721 267,601 236,778 Total net product revenues $ 1,172,109 $ 672,212 $ 2,208,236 $ 1,140,750 As of June 30, 2026 and December 31, 2025, net product revenue-related receivables of $ 787.8 million and $ 669.5 million, respectively, were included in accounts receivable, net on our condensed consolidated balance sheets. 12 Table of Contents ALNYLAM PHARMACEUTICALS, INC. NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Unaudited) The following table summarizes balances and activity in each product revenue allowance and reserve category: (In thousands) Chargebacks and Rebates Other Incentives and Allowances Total Beginning balance as of December 31, 2025 $ 399,853 $ 25,797 $ 425,650 Provision related to current year sales 602,876 62,545 665,421 Provision related to prior years’ sales ( 2,166 ) ( 992 ) ( 3,158 ) Credit or payments made during the period for current year sales ( 337,561 ) ( 42,398 ) ( 379,959 ) Credit or payments made during the period for prior years’ sales ( 189,730 ) ( 15,385 ) ( 205,115 ) Total as of June 30, 2026 $ 473,272 $ 29,567 $ 502,839 4. COLLABORATIONS Product Collaborations Net revenues from collaborations consisted of the following: Three Months Ended June 30, Six Months Ended June 30, (In thousands) 2026 2025 2026 2025 Roche $ 41,888 $ 18,267 $ 77,529 $ 35,323 Regeneron Pharmaceuticals 5,020 32,542 51,356 83,581 Other 257 10,687 355 41,777 Total net revenues from collaborations $ 47,165 $ 61,496 $ 129,240 $ 160,681 The following table presents the balance of our receivables and contract liabilities related to our collaboration agreements: (In thousands) As of June 30, 2026 As of December 31, 2025 Receivables included in accounts receivable, net $ 58,664 $ 48,823 Contract liabilities included in deferred revenue $ 4,014 $ 4,845 We recognized net revenues from collaborations of $( 0.8 ) million and $ 4.1 million in the three and six months ended June 30, 2026, respectively, and $ 13.0 million and $ 41.1 million in the three and six months ended June 30, 2025, respectively, each of which was included in the contract liability balance at the beginning of the applicable period. To determine revenue recognized in the period from contract liabilities, we first allocate revenue to the individual contract liability balance outstanding at the beginning of the period until the revenue exceeds that balance. If additional consideration is received on those contracts in subsequent periods, we assume all revenue recognized in the reporting period first applies to the beginning contract liability as opposed to a portion applying to the new consideration for the period. Roche On July 21, 2023, or the Effective Date, we entered into a Collaboration and License Agreement, or the Roche Agreement, with F. Hoffmann-La Roche Ltd. and Genentech, Inc., or, collectively, Roche, pursuant to which we and Roche established a worldwide, strategic collaboration for the joint development of zilebesiran. Zilebesiran is our investigational small interfering RNA, or siRNA, therapeutic targeting liver-expressed angiotensinogen, which is currently in Phase 3 clinical development for the treatment of hypertension. Under the Roche Agreement, we granted to Roche (i) co-exclusive rights to develop zilebesiran worldwide and commercialize zilebesiran in the U.S., referred to as the Co-Commercialization Territory, (ii) exclusive rights to commercialize zilebesiran outside of the U.S., referred to as the Roche Territory, and (iii) non-exclusive rights to manufacture zilebesiran for the development and commercialization of zilebesiran in the Roche Territory. We lead the global clinical development for zilebesiran. We are responsible for forty percent ( 40 %) and Roche is responsible for the remaining sixty percent ( 60 %) of development costs incurred in the conduct of development activities that support regulatory approval of zilebesiran globally. We and Roche share equally ( 50 / 50 ) all costs incurred in connection with development activities that are conducted to support regulatory approval of zilebesiran solely in the Co-Commercialization 13 Table of Contents ALNYLAM PHARMACEUTICALS, INC. NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Unaudited) Territory if incremental development activities are needed. Roche is solely responsible for all costs incurred in the conduct of development activities that primarily support regulatory approval in the Roche Territory. Upon regulatory approval, Roche has the exclusive right to commercialize zilebesiran in the Roche Territory and will pay us tiered, low double-digit royalties based on net sales of zilebesiran on a country-by-country basis during the applicable royalty term. We and Roche will co-commercialize zilebesiran in the Co-Commercialization Territory and share equally ( 50 / 50 ) in profits and losses (including commercialization costs). Roche has the right to terminate the Roche Agreement for any or no reason at all upon prior written notice. In addition, either party may terminate the Roche Agreement for a material breach by, or insolvency of, the other party, subject to a cure period. Unless earlier terminated pursuant to its terms, the Roche Agreement will remain in effect until expiration on a country-by-country basis (a) in the Roche Territory, upon expiration of the applicable royalty term in the applicable country and (b) in the Co-Commercialization Territory, upon expiration of the term of the co-commercialization efforts. As of the Effective Date, we identified the following promises in the Roche Agreement that were evaluated under the scope of Accounting Standards Codification, or ASC, Topic 606, Revenue from Contracts with Customers, or ASC 606: (i) a co-exclusive license to develop zilebesiran worldwide and commercialize zilebesiran within the Co-Commercialization Territory, a non-exclusive license to manufacture zilebesiran in the Roche Territory solely for purposes of developing and commercializing zilebesiran in the Roche Territory, and an exclusive license to commercialize zilebesiran in the Roche Territory, collectively referred to as Roche License Obligation, (ii) development services, including the manufacture of clinical supply, that support regulatory approval of zilebesiran, referred to as the Roche Development Services Obligation, and (iii) a technology transfer of the existing manufacturing process for zilebesiran, referred to as the Roche Technology Transfer Obligation. The three performance obligations under the Roche Agreement are collectively referred to as the Roche Performance Obligations. We determined that the Roche License Obligation, Roche Development Services Obligation and Roche Technology Transfer Obligation were reflective of a vendor-customer relationship and therefore represented performance obligations within the scope of ASC 606. The Roche License Obligation was considered functional intellectual property and distinct from other promises under the contract as Roche can benefit from the licenses on its own or together with other readily available resources. As the licenses were delivered at the same time, they were considered one performance obligation at contract inception. The Roche Development Services Obligation was considered distinct as Roche could benefit from the development services together with the licenses transferred by us at the inception of the agreement. The development services are not expected to significantly modify or customize the initial intellectual property as zilebesiran was in Phase 2 of clinical development at contract inception. The Roche Technology Transfer Obligation was distinct as Roche can benefit from the manufacturing license transferred by us at the inception of the agreement given the advancements of our RNAi platform and our utilization of third-party contract manufacturing organizations to manufacture zilebesiran. Therefore, each represented a separate performance obligation within the contract with a customer under the scope of ASC 606 at contract inception. We consider the collaborative activities associated with the co-commercialization of zilebesiran in the U.S. to be a separate unit of account within the scope of ASC Topic 808, Collaborative Arrangements , as we and Roche are both active participants in the commercialization activities and are exposed to significant risks and rewards that are dependent on the commercial success of the activities in the arrangement. Based on the standalone selling prices of each performance obligation as of the Effective Date, we allocated the variable consideration related to the estimated reimbursements for the Roche Development Services Obligation and the Roche Technology Transfer Obligation to each performance obligation as the terms of the variable payment relate specifically to our efforts to satisfy the performance obligation. We allocated the fixed upfront consideration entirely to the Roche License Obligation as the value of the fixed consideration together with the expected value of the remaining development and regulatory milestones, sales-based milestones, and royalties, all of which are either currently constrained at inception or subject to the sales- or usage-based royalty exception, approximates the standalone selling price of the Roche License Obligation. This allocation is consistent with the allocation objective of ASC 606 when considering all of the performance obligations and payment terms in the contract. The Roche License Obligation was satisfied at a point in time upon transfer of the license to Roche. Control of the licenses was transferred on the Effective Date and Roche could begin to use and benefit from the licenses. Because of this, all consideration allocated to the Roche License Obligation, including the upfront payment, milestones and royalties, is recognized when these amounts are no longer considered fully constrained or when the related sales occur for amounts subject to the sales-or-usage based royalty exception of ASC 606. For the Roche Development Services Obligation, we measure proportional performance over time using an input method based on cost incurred relative to the total estimated cost of the obligation, on a quarterly basis, by determining the proportion of effort incurred as a percentage of total effort we expect to expend. This ratio is applied to the transaction price allocated to the obligation. As all costs in the proportional performance model are allowable for reimbursement from Roche, and the assumptions used to determine the total estimated cost of the obligation are consistent with the assumptions used to determine the transaction price allocated to the obligation, the revenue recognized for this obligation 14 Table of Contents ALNYLAM PHARMACEUTICALS, INC. NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Unaudited) will approximate 60 % of the actual reimbursable cost incurred. Management has applied significant judgment in the process of developing our estimates. We re-evaluate the transaction price as of the end of each reporting period and as of June 30, 2026, the total transaction price was determined to be $ 1.74 billion. The following table provides a summary of the transaction price allocated to each performance obligation: (In thousands) As of June 30, 2026 Roche License Obligation $ 675,000 Roche Development Services Obligation 1,061,167 Roche Technology Transfer Obligation 2,000 $ 1,738,167 Net revenues from collaborations recognized under the Roche Agreement consisted of the following: Three Months Ended June 30, Six Months Ended June 30, (In thousands) 2026 2025 2026 2025 Roche Development Services Obligation $ 40,233 $ 16,690 74,639 32,530 Other 1,655 1,577 2,890 2,793 Total $ 41,888 $ 18,267 $ 77,529 $ 35,323 As of June 30, 2026, the aggregate amount of the transaction price allocated to the Roche Performance Obligations that was unsatisfied was $ 829.8 million, which is expected to be recognized through the term of the Roche Agreement based on our input method model as the services are performed. We incurred research and development costs related to our collaboration with Roche of $ 73.3 million and $ 134.5 million during the three and six months ended June 30, 2026, respectively, and $ 31.0 million and $ 60.7 million during the three and six months ended June 30, 2025, respectively. Regeneron Pharmaceuticals, Inc. Overview In 2019, we entered into a global, strategic collaboration with Regeneron Pharmaceuticals, Inc., or Regeneron, to discover, develop and commercialize RNAi therapeutics for a broad range of diseases by addressing therapeutic targets expressed in the eye and central nervous system, or CNS, in addition to a select number of targets expressed in the liver, which we refer to as the Regeneron Collaboration. The Regeneron Collaboration is governed by a Master Agreement, referred to as the Regeneron Master Agreement. In connection with the Regeneron Master Agreement, we and Regeneron entered into (i) a co-co collaboration agreement covering the continued development of cemdisiran, our C5 siRNA, currently in development for C5 complement-mediated diseases, as a monotherapy, or the C5 Co-Co Collaboration Agreement, and (ii) a license agreement to evaluate anti-C5 antibody-siRNA combinations for C5 complement-mediated diseases including evaluating the combination of Regeneron’s pozelimab and cemdisiran, or the C5 License Agreement. The Master Agreement, the C5 Co-Co Collaboration Agreement and the C5 License Agreement were accounted for as a single arrangement because the agreements were negotiated together. In November 2022, Regeneron exercised its right under the C5 Co-Co Collaboration Agreement to opt-out of the further development and commercialization of cemdisiran monotherapy. As a result of Regeneron’s decision to opt-out, the licenses granted to Regeneron under the C5 Co-Co Collaboration Agreement reverted to us, we had the sole right to continue to develop and commercialize cemdisiran monotherapy, and Regeneron no longer shared in the costs on any monotherapy program. Regeneron remained eligible to receive tiered, double-digit royalties on net sales of cemdisiran as a monotherapy. In June 2024, we entered into an amended and restated C5 License Agreement, or the Amended C5 License Agreement, which terminated the C5 Co-Co Collaboration Agreement and granted Regeneron a worldwide license to cemdisiran as a monotherapy in addition to the license to cemdisiran in combination with anti-C5 antibodies. Through the Amended C5 License Agreement, Regeneron is now solely responsible for development, manufacturing and commercialization of cemdisiran as a monotherapy and in combination with anti-C5 antibodies. As part of the Amended C5 License Agreement, we provided manufacturing technology transfer services for cemdisiran to Regeneron. Regeneron provided us with an upfront payment of $ 10.0 million, and we will receive certain milestone payments upon receipt of regulatory approval for cemdisiran as a monotherapy, and tiered double-digit royalties on net sales. The Amended C5 License Agreement did not change our rights to receive low double-digit royalties and commercial milestones of up to $ 325.0 million on any potential product sales if cemdisiran is used as part of a combination product. 15 Table of Contents ALNYLAM PHARMACEUTICALS, INC. NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Unaudited) Under the terms of the Regeneron Collaboration, we worked exclusively with Regeneron to discover RNAi therapeutics for eye and CNS diseases and a select number of target genes expressed in the liver for an initial research period, or the Initial Research Term. The Initial Research Term expired in May 2026. As a result of such expiration, we will no longer work exclusively with Regeneron to discover RNAi therapeutics for eye and CNS diseases. We will, however, continue to collaborate exclusively with Regeneron on the programs targeting gene targets that were nominated during the Initial Research Term, provided that lead candidates for such targets are designated within two years of the expiration of the Initial Research Term. Regeneron leads development and commercialization for all programs targeting eye diseases (subject to limited exceptions), entitling us to certain potential milestone and royalty payments pursuant to the terms of a license agreement, the form of which has been agreed upon by the parties. We and Regeneron are alternating leadership on CNS and liver programs, with the lead party retaining global development and commercial responsibility. For such CNS and liver programs, both we and Regeneron have the option at lead candidate selection to enter into a co-co collaboration agreement, the form of which has been agreed upon by the parties, whereby both companies will share equally all costs of, and profits from, all development and commercialization activities under the program. If the non-lead party elects to not enter into a co-co collaboration agreement with respect to a given CNS or liver program, we and Regeneron will enter into a license agreement with respect to such program and the lead party will be the “Licensee” for the purposes of the license agreement. If the lead party for a CNS or liver program elects to not enter into the co-co collaboration agreement, then we and Regeneron will enter into a license agreement with respect to such program and leadership of the program will transfer to the other party and the former non-lead party will be the “Licensee” for the purposes of the license agreement. In connection with the Regeneron Master Agreement, we remain eligible to receive an additional $ 100.0 million milestone payment upon achievement of certain criteria during early clinical development for an eye program. We and Regeneron are continuing to advance programs nominated during the Initial Research Term. For each of these programs, Regeneron will provide us with $ 2.5 million in funding at program initiation and an additional $ 2.5 million at lead candidate identification. For any license agreement subsequently entered into, the licensee will generally be responsible for its own costs and expenses incurred in connection with the development and commercialization of the collaboration products. The licensee will pay to the licensor certain development and/or commercialization milestone payments totaling up to $ 150.0 million for each collaboration product. In addition, following the first commercial sale of the applicable collaboration product under a license agreement, the licensee is required to make certain tiered royalty payments, ranging from low double-digits up to 20 %, to the licensor based on the aggregate annual net sales of the collaboration product, subject to customary reductions. For any co-co collaboration agreement subsequently entered into, we and Regeneron will share equally all costs of, and profits from, development and commercialization activities. Reimbursement of our share of costs will be recognized as a reduction to research and development expense in the condensed consolidated statements of operations and comprehensive income (loss). In the event that a party exercises its opt-out right, the lead party will be responsible for all costs and expenses incurred in connection with the development and commercialization of the collaboration products under the applicable co-co collaboration agreement, subject to continued sharing of costs through defined points. If a party exercises its opt-out right, following the first commercial sale of the applicable collaboration product under a co-co collaboration agreement, the lead party is required to make certain tiered royalty payments, ranging from low double-digits up to 20 %, to the other party based on the aggregate annual net sales of the collaboration product and the timing of the exercise of the opt-out right, subject to customary reductions and a reduction for opt-out transition costs. Contract Modification In June 2024, we determined the Amended C5 License Agreement does not meet the requirements to account for the contract modification as a separate contract under ASC 606 because the consideration exchanged for the additional distinct goods and services does not reflect the standalone selling price. Therefore, we have accounted for the Amended C5 License Agreement and Regeneron Master Agreement as a single combined contract. The modification date was determined to be the June 2024 effective date of the Amended C5 License Agreement. Our performance obligations subsequent to the contract modification included: (i) a research license and research services, collectively referred to as the Research Services Obligation; (ii) a worldwide license to cemdisiran for combination therapies, and manufacturing and development service obligations, collectively referred to as the C5 License Obligation; (iii) a worldwide license to cemdisiran for monotherapies, referred to as the C5 Monotherapy Obligation; and (iv) a technology transfer of the existing manufacturing process for cemdisiran, referred to as the Regeneron Technology Transfer Obligation. The Amended C5 License Agreement did not change the Research Services Obligation or the C5 License Obligation, which were both performance obligations at the inception of our global, strategic collaboration with Regeneron prior to the contract modification. The Amended C5 License Agreement resulted in two additional performance obligations, which were the C5 Monotherapy Obligation and the Regeneron Technology Transfer Obligation. The C5 Monotherapy Obligation was considered functional intellectual property and distinct from other promises as Regeneron can benefit from the cemdisiran 16 Table of Contents ALNYLAM PHARMACEUTICALS, INC. NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Unaudited) monotherapy license on its own or together with other readily available resources and the license is separately identifiable from the other promises in the contract. The Regeneron Technology Transfer Obligation was distinct as Regeneron can benefit from the cemdisiran monotherapy license transferred by us without the technology transfer given cemdisiran was in an advanced stage of clinical development and our utilization of third-party contract manufacturing organizations to manufacture cemdisiran. Therefore, the C5 Monotherapy Obligation and the Regeneron Technology Transfer Obligation each represented a separate performance obligation. The initial transaction price of $ 191.5 million allocated to the C5 Monotherapy Obligation was recognized immediately as this obligation was satisfied at a point in time upon transfer of the license to Regeneron. Control of the license was transferred in June 2024 as Regeneron could begin to use and benefit from the license on its own or together with other readily available resources to generate economic benefit from the license. The remaining variable consideration allocated to the C5 Monotherapy Obligation, including milestones and royalties, will be recognized immediately when these amounts are no longer considered fully constrained or when the related sales occur for amounts subject to the sales-or-usage based royalty exception of ASC 606. In the three months ended March 31, 2025, we completed our obligations related to the C5 License Obligation and the Regeneron Technology Transfer Obligation. We continue to perform work in satisfaction of the remaining unsatisfied performance obligation, the Research Services Obligation. For this performance obligation, we measure proportional performance over time using an input method based on cost incurred relative to the total estimated costs for each of the identified obligations by determining the proportion of effort incurred as a percentage of total effort we expect to expend. This ratio is applied to the transaction price allocated to the obligation. Management has applied significant judgment in the process of developing our estimates. Any changes to these estimates will be recognized in the period in which they change as a cumulative catch-up. We re-evaluate the transaction price as of the end of each reporting period and as of June 30, 2026, the total transaction price was determined to be $ 100.5 million related to this obligation. As of June 30, 2026, the aggregate amount of the transaction price that was unsatisfied was $ 28.2 million, which is expected to be recognized through the term of the Regeneron Collaboration based on our input method model as the services are performed. Net revenues from collaborations recognized under the Regeneron Collaboration consisted of the following: Three Months Ended June 30, Six Months Ended June 30, (In thousands) 2026 2025 2026 2025 Research Services Obligation $ ( 802 ) $ 12,957 $ 5,831 $ 26,767 C5 License Obligation — — — 21,458 Regeneron Technology Transfer Obligation — — — 2,431 Other license programs 5,822 19,585 45,525 32,925 Total $ 5,020 $ 32,542 $ 51,356 $ 83,581 Revenue recognized for the “Other license programs” relates to eleven separate programs subject to individual agreements with Regeneron. Deferred revenue is classified as either current or noncurrent in the condensed consolidated balance sheets based on the period the revenue is expected to be recognized. Current deferred revenue was $ 4.0 million and $ 4.8 million as of June 30, 2026 and December 31, 2025, respectively, related only to the Research Services Obligation. We incurred research and development costs related to the Regeneron Collaboration of $ 12.2 million and $ 23.2 million during the three and six months ended June 30, 2026, respectively, and $ 12.5 million and $ 31.5 million during the three and six months ended June 30, 2025, respectively. Vir Biotechnology, Inc. In March 2025, we and Vir Biotechnology, Inc., or Vir, entered into an amended and restated collaboration and license agreement, or the Amended Vir Agreement, relating to elebsiran (formerly ALN-HBV02 (VIR-2218)). Vir remains solely responsible for development, manufacturing and commercialization of elebsiran. In connection with execution of the Amended Vir Agreement, Vir made a $ 30.0 million payment, and we remain entitled to receive milestone payments upon the achievement of specified regulatory and commercial milestones, and royalties on the net sales of elebsiran ranging from low-to-mid teen percentages. Because the license rights have already been delivered and we have no other remaining performance obligations under the Amended Vir Agreement, the $ 30.0 million payment was recognized within net revenues from collaborations during the three months ended March 31, 2025. 17 Table of Contents ALNYLAM PHARMACEUTICALS, INC. NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Unaudited) Other Collaborations In addition to the collaboration agreements discussed above, we have various other collaboration agreements that are not individually significant to our operating results or financial condition at this time. Pursuant to the terms of those agreements, we may be required to pay, or we may receive, additional amounts contingent upon the occurrence of various future events (e.g., upon the achievement of various development and commercial milestones) which in the aggregate could be significant. We may also incur, or be reimbursed for, significant research and development costs. In addition, if any products related to these collaborations are approved for sale, we may be required to pay, or we may receive, royalties on future sales. The payment or receipt of these amounts, however, is contingent upon the occurrence of various future events. Due to the uncertainty of pharmaceutical development and the high historical failure rates generally associated with drug development and commercialization, it is possible we may not receive any such payments under all of our existing collaboration and license agreements, including the agreements described within this note. Inceptive Nucleics, Inc. In June 2026, we entered into a collaboration agreement with Inceptive Nucleics, Inc., or Inceptive, that is designed to accelerate the discovery of novel RNAi therapeutics by integrating Inceptive’s generative AI models with our pipeline, which we refer to as the Inceptive Collaboration. Under the terms of the Inceptive Collaboration, we and Inceptive will jointly conduct multiple research programs to develop drug discovery models. The Inceptive Collaboration will be governed by a joint steering committee. The initial research term of the Inceptive Collaboration is three years and may be extended by mutual agreement of the parties. Inceptive granted to us an exclusive, worldwide, perpetual and irrevocable, royalty-free, transferable, sublicensable license, to certain of its intellectual property to exploit compounds and products developed as part of the Inceptive Collaboration. We have the unilateral right to terminate the Inceptive Collaboration at any time, in its entirety or on a research program-by-research program basis, upon 30 days’ advance written notice to Inceptive. We also entered into a stock purchase agreement with Inceptive pursuant to which we purchased shares of Inceptive’s preferred stock for a total purchase price of $ 15.0 million. The preferred shares we purchased represented a mid-single digit ownership interest in the outstanding equity of Inceptive. The investment in preferred stock is a variable interest and Inceptive is a variable interest entity, however, we are not the primary beneficiary as we do not have the power to direct the activities that most significantly impact the economic performance of Inceptive. The investment in Inceptive’s preferred stock does not have a readily determinable fair value. We recognized the investment at cost and will adjust the carrying value for any impairments, plus or minus changes resulting from observable price changes in orderly transactions for the identical or a similar investment of the same issuer. The investment in preferred stock is recorded in other assets on the consolidated balance sheet as of June 30, 2026. 5. FAIR VALUE MEASUREMENTS The following tables present information about our financial assets that are measured at fair value on a recurring basis and indicate the fair value hierarchy of the valuation techniques we utilized to determine such fair value: (In thousands) As of June 30, 2026 Quoted Prices in Active Markets (Level 1) Significant Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Financial assets Cash equivalents: Money market funds 141,609 141,609 — — Marketable debt securities: U.S. treasury securities 808,038 — 808,038 — Corporate notes 437,947 — 437,947 — U.S. government-sponsored enterprise securities 339,623 — 339,623 — Commercial paper 14,221 — 14,221 — Restricted cash (money market funds) 569 569 — — Total financial assets $ 1,742,007 $ 142,178 $ 1,599,829 $ — 18 Table of Contents ALNYLAM PHARMACEUTICALS, INC. NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Unaudited) (In thousands) As of December 31, 2025 Quoted Prices in Active Markets (Level 1) Significant Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Financial assets Cash equivalents: Money market funds $ 140,445 $ 140,445 $ — $ — U.S. treasury securities 18,952 — 18,952 — U.S. government-sponsored enterprise securities 2,690 — 2,690 — Commercial paper 1,995 — 1,995 — Marketable debt securities: U.S. treasury securities 653,341 — 653,341 — Corporate notes 333,241 — 333,241 — U.S. government-sponsored enterprise securities 252,634 — 252,634 — Commercial paper 7,017 — 7,017 — Municipal securities 5,001 — 5,001 — Restricted cash (money market funds) 917 917 — — Total financial assets $ 1,416,233 $ 141,362 $ 1,274,871 $ — During the three and six months ended June 30, 2026 and 2025, there were no transfers into or out of Level 3 financial assets or liabilities. The carrying amounts reflected on our condensed consolidated balance sheets for cash, accounts receivable, net, other current assets, accounts payable and accrued expenses approximate fair value due to their short-term maturities. 6. MARKETABLE DEBT SECURITIES We invest our excess cash balances in marketable debt securities and, at each balance sheet date presented, we classify all of our investments in debt securities as available-for-sale and as current assets as they represent the investment of funds available for current operations. We did not record any impairment charges related to our marketable debt securities during the three and six months ended June 30, 2026 or 2025. The following tables summarize our marketable debt securities: As of June 30, 2026 (In thousands) Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value U.S. treasury securities $ 810,231 $ 163 $ ( 2,356 ) $ 808,038 Corporate notes 438,660 161 ( 874 ) 437,947 U.S. government-sponsored enterprise securities 340,633 30 ( 1,040 ) 339,623 Commercial paper 14,232 — ( 11 ) 14,221 Total $ 1,603,756 $ 354 $ ( 4,281 ) $ 1,599,829 As of December 31, 2025 (In thousands) Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value U.S. treasury securities $ 670,566 $ 1,736 $ ( 9 ) $ 672,293 Corporate notes 332,104 1,152 ( 15 ) 333,241 U.S. government-sponsored enterprise securities 254,829 559 ( 64 ) 255,324 Commercial paper 9,012 — — 9,012 Municipal securities 5,000 1 — 5,001 Total $ 1,271,511 $ 3,448 $ ( 88 ) $ 1,274,871 19 Table of Contents ALNYLAM PHARMACEUTICALS, INC. NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Unaudited) The fair values of our marketable debt securities by classification in the condensed consolidated balance sheets were as follows: (In thousands) As of June 30, 2026 As of December 31, 2025 Marketable debt securities $ 1,599,829 $ 1,251,234 Cash and cash equivalents — 23,637 Total $ 1,599,829 $ 1,274,871 7. OTHER BALANCE SHEET DETAILS Inventory The components of inventory are summarized as follows: (In thousands) As of June 30, 2026 As of December 31, 2025 Raw materials $ 13,913 $ 14,184 Work in process 59,045 65,122 Finished goods 44,037 32,338 Total inventory $ 116,995 $ 111,644 As of June 30, 2026 and December 31, 2025, we had $ 19.9 million and $ 28.9 million, respectively, of long-term inventory included within other assets in our condensed consolidated balance sheets as we anticipate it being consumed beyond our normal operating cycle. Cash, Cash Equivalents and Restricted Cash The following table provides a reconciliation of cash, cash equivalents and restricted cash reported within our condensed consolidated balance sheets to the totals of these amounts shown in the condensed consolidated statements of cash flows: As of June 30, (In thousands) 2026 2025 Cash and cash equivalents $ 1,708,318 $ 1,113,685 Total restricted cash included in other assets 1,160 2,176 Total cash, cash equivalents, and restricted cash shown in the condensed consolidated statements of cash flows $ 1,709,478 $ 1,115,861 Accumulated Other Comprehensive Loss The following tables summarize the changes in accumulated other comprehensive loss, by component: (In thousands) Loss on Investment in Joint Venture Defined Benefit Pension Plans, Net of Tax Unrealized Gains (Losses) from Debt Securities Foreign Currency Translation Adjustment Total Accumulated Other Comprehensive Loss Balance as of December 31, 2025 $ ( 32,792 ) $ ( 3,268 ) $ 3,360 $ 12,603 $ ( 20,097 ) Other comprehensive loss before reclassifications — — ( 5,272 ) ( 4,932 ) ( 10,204 ) Amounts reclassified from accumulated other comprehensive loss — 178 ( 2,015 ) — ( 1,837 ) Net other comprehensive income (loss) — 178 ( 7,287 ) ( 4,932 ) ( 12,041 ) Balance as of June 30, 2026 $ ( 32,792 ) $ ( 3,090 ) $ ( 3,927 ) $ 7,671 $ ( 32,138 ) 20 Table of Contents ALNYLAM PHARMACEUTICALS, INC. NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Unaudited) (In thousands) Loss on Investment in Joint Venture Defined Benefit Pension Plans, Net of Tax Unrealized Gains (Losses) from Debt Securities Foreign Currency Translation Adjustment Total Accumulated Other Comprehensive Loss Balance as of December 31, 2024 $ ( 32,792 ) $ ( 4,249 ) $ 1,544 $ 979 $ ( 34,518 ) Other comprehensive income before reclassifications — — 1,580 3,771 5,351 Amounts reclassified from accumulated other comprehensive loss — 108 ( 893 ) — ( 785 ) Net other comprehensive income — 108 687 3,771 4,566 Balance as of June 30, 2025 $ ( 32,792 ) $ ( 4,141 ) $ 2,231 $ 4,750 $ ( 29,952 ) Amounts reclassified out of accumulated other comprehensive loss relate to settlements of marketable debt securities and amortization of our pension obligation which are recorded as other income (expense), net in the condensed consolidated statements of operations and comprehensive income (loss). 8. CONVERTIBLE DEBT AND OTHER FINANCING Convertible Senior Notes Due 2028 On September 8, 2025, we commenced a private offering of $ 575.0 million in aggregate principal amount of 0.00 % convertible senior notes due 2028, or the Initial 2028 Notes. On September 10, 2025, the initial purchasers in such offering exercised their option to purchase an additional $ 86.3 million in aggregate principal amount of our 0.00 % Convertible Senior Notes due 2028, or the Additional 2028 Notes, and together with the Initial 2028 Notes referred to as the 2028 Notes, bringing the total aggregate principal amount of the 2028 Notes issued and outstanding to $ 661.3 million. The 2028 Notes are our senior unsecured obligations. The 2028 Notes were issued pursuant to an indenture, dated September 12, 2025, or the 2025 Indenture, between us and The Bank of New York Mellon, as trustee. The 2025 Indenture includes customary covenants and sets forth certain events of default after which the 2028 Notes may be declared immediately due and payable and sets forth certain types of bankruptcy or insolvency events of default involving us after which the 2028 Notes become automatically due and payable. The 2028 Notes will mature on September 15, 2028, unless earlier converted, redeemed or repurchased. The 2028 Notes will not bear regular interest. Before June 15, 2028, noteholders will have the right to convert their 2028 Notes in certain circumstances and during specified periods: (1) during any calendar quarter commencing after the calendar quarter ending on December 31, 2025 (and only during such calendar quarter), if the last reported sale price of our common stock for at least 20 trading days (whether or not consecutive) during a period of 30 consecutive trading days ending on, and including, the last trading day of the immediately preceding calendar quarter is greater than or equal to 130 % of the conversion price on each applicable trading day; (2) during the five business day period after any ten consecutive trading day period in which the trading price per $1,000 principal amount of the 2028 Notes for each trading day of that ten consecutive trading day period was less than 98 % of the product of the last reported sale price of our common stock and the conversion rate on such trading day; (3) if we call any or all of the 2028 Notes for redemption; or (4) upon the occurrence of specified corporate events. From and after June 15, 2028, the 2028 Notes will be convertible at the option of the noteholders at any time prior to the close of business on the second scheduled trading day immediately preceding the maturity date. We will settle any conversions of the 2028 Notes by paying or delivering, as applicable, cash, shares of our common stock, or a combination of cash and shares of common stock, at our election. The conversion rate for the 2028 Notes will initially be 1.4923 shares of common stock per $1,000 principal amount of 2028 Notes, which is equivalent to an initial conversion price of approximately $ 670.11 per share of common stock. The initial conversion price represents a premium of approximately 40 % above the U.S. composite volume weighted average price of our common stock from 12:30 p.m. through 4:00 p.m. Eastern Daylight Time on September 9, 2025, which was $ 478.63 per share. The conversion rate is subject to adjustment under certain circumstances in accordance with the terms of the 2025 Indenture. We may not redeem the 2028 Notes prior to September 20, 2027. We may redeem for cash all or any portion of the 2028 Notes (subject to certain limitations), at our option, on or after September 20, 2027 and on or prior to the 21st scheduled trading day immediately preceding the maturity date, if the last reported sale price of our common stock has been at least 130 % of the conversion price then in effect for at least 20 trading days (whether or not consecutive), including the trading day immediately preceding the date on which we provide notice of redemption, during any 30 consecutive trading day period ending on, and including, the trading day immediately preceding the date on which we provide notice of redemption at a redemption price equal to 100 % of the principal amount of the 2028 Notes to be redeemed, plus any accrued and unpaid special interest to, but 21 Table of Contents ALNYLAM PHARMACEUTICALS, INC. NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Unaudited) excluding, the redemption date. No sinking fund is provided for the 2028 Notes, which means that we are not required to redeem or retire the 2028 Notes periodically. If we undergo a fundamental change, which includes certain change of control events or a termination of trading of our common stock, then subject to certain conditions, holders may require us to repurchase for cash all or any portion of their notes at a fundamental change repurchase price equal to 100 % of the principal amount of the 2028 Notes to be repurchased plus accrued and unpaid special interest. In addition, if specific corporate events occur prior to the maturity date or if we issue a notice of redemption, we will increase the conversion rate by pre-defined amounts for holders who elect to convert their notes in connection with such corporate event. The conditions allowing holders of the 2028 Notes to convert were not met during the quarter ended June 30, 2026. The 2028 Notes were issued at par. As of June 30, 2026 and December 31, 2025, the 2028 Notes were classified as a long-term liability on the condensed consolidated balance sheets and had a carrying value of $ 649.8 million and $ 647.2 million, respectively, representing the outstanding principal amount, net of unamortized issuance costs of $ 11.5 million and $ 14.0 million, respectively. The issuance costs are amortized to interest expense over the contractual term of the 2028 Notes. As of June 30, 2026 and December 31, 2025, the estimated fair value of the 2028 Notes was approximately $ 607.4 million and $ 637.0 million, respectively, which was determined based on the last actively traded price per $100 of the 2028 Notes (Level 2) on that day. As of June 30, 2026 and December 31, 2025, the effective interest rate of the 2028 Notes was 1 %. We used the net proceeds from the issuance of the 2028 Notes to pay the cost of the 2025 Capped Call Transactions, and the remainder of the net proceeds, together with cash on hand, to repay $ 637.8 million aggregate principal amount of the 2027 Notes, as further discussed below. 2025 Capped Call Transactions In September 2025, in connection with the pricing of the 2028 Notes, we entered into privately negotiated capped call transactions, or 2025 Capped Call Transactions. The 2025 Capped Call Transactions initially cover, subject to customary anti-dilution adjustments, the number of shares of common stock that underlie the 2028 Notes. The initial cap price of the 2025 Capped Call Transactions is $ 837.61 per share, and is subject to certain adjustments under the terms of the 2025 Capped Call Transactions. The 2025 Capped Call Transactions are not part of the terms of the 2028 Notes and are accounted for as separate transactions. As these transactions are indexed to our own stock and are considered equity classified, they are recorded in stockholders’ equity and are not accounted for as derivatives. The cost incurred in connection with the 2025 Capped Call Transactions of $ 35.3 million was recorded as a reduction to additional paid-in capital on our condensed consolidated balance sheet and the fair value of the capped call instrument is not remeasured each reporting period. Convertible Senior Notes Due 2027 On September 12, 2022, we commenced a private offering of $ 900.0 million in aggregate principal amount of 1.00 % Convertible Senior Notes due 2027, or the Initial 2027 Notes. On September 13, 2022, the initial purchasers in such offering exercised their option to purchase an additional $ 135.0 million in aggregate principal amount of our 1.00 % Convertible Senior Notes due 2027, or the Additional 2027 Notes, and together with the Initial 2027 Notes collectively referred to as the 2027 Notes, bringing the total aggregate principal amount of the 2027 Notes to $ 1.04 billion. The 2027 Notes were issued pursuant to an indenture, dated September 15, 2022, or the 2022 Indenture. The 2022 Indenture includes customary covenants and sets forth certain events of default after which the 2027 Notes may be declared immediately due and payable and sets forth certain types of bankruptcy or insolvency events of default involving us after which the 2027 Notes become automatically due and payable. The 2027 Notes were issued at par. The 2027 Notes will mature on September 15, 2027, unless earlier converted, redeemed or repurchased. The 2027 Notes bear interest at a rate of 1.00 % per year payable semiannually in arrears on March 15 and September 15 of each year, beginning on March 15, 2023. The 2027 Notes are convertible at the option of the noteholder on or after June 15, 2027. Prior to June 15, 2027, the 2027 Notes are convertible only under the following circumstances: (1) during any calendar quarter commencing after the calendar quarter ending on December 31, 2022 (and only during such calendar quarter), if the last reported sale price of our common stock for at least 20 trading days (whether or not consecutive) during a period of 30 consecutive trading days ending on, and including, the last trading day of the immediately preceding calendar quarter is greater than or equal to 130 % of the conversion price on each applicable trading day; (2) during the five business day period after any ten consecutive trading day period in which the trading price per $1,000 principal amount of the 2027 Notes for each trading day of that ten consecutive trading day period was less than 98 % of the product of the last reported sale price of our common stock and the conversion rate of the 2027 Notes on such trading day; (3) if we call any or all of the 2027 Notes for redemption; or (4) upon the occurrence of specific corporate events as set forth in the 2022 Indenture governing the 2027 Notes. 22 Table of Contents ALNYLAM PHARMACEUTICALS, INC. NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Unaudited) We will settle any conversions of the 2027 Notes by paying or delivering, as applicable, cash, shares of our common stock, or a combination of cash and shares of common stock, at our election. The initial conversion rate for the 2027 Notes is 3.4941 shares of common stock per $1,000 principal amount, which is equivalent to an initial conversion price of approximately $ 286.20 per share of common stock, which represents a premium of approximately 35 % over the last reported sale price of common stock of $ 212.00 per share on September 12, 2022. The conversion rate is subject to adjustment under certain circumstances in accordance with the terms of the 2022 Indenture. The condition allowing holders of the 2027 Notes to convert was not met in the second quarter of 2026, and the 2027 Notes will not be convertible in the third quarter of 2026. We are able to redeem the 2027 Notes after September 20, 2025. We may redeem for cash equal to 100 % of the principal amount of the 2027 Notes being redeemed plus accrued and unpaid interest of all or any portion of the 2027 Notes, at our option, on or after September 20, 2025, if the last reported sales price of our common stock has been at least 130 % of the conversion price then in effect for at least 20 trading days (whether or not consecutive) during any 30 consecutive trading day period. As of June 30, 2026, we have not redeemed any of the 2027 Notes under this option. No sinking fund is provided for the 2027 Notes and therefore we are not required to redeem or retire the 2027 Notes periodically. If we undergo a fundamental change, which includes certain change of control events or a termination of trading of our common stock, then subject to certain conditions, holders may require us to repurchase for cash all or any portion of their 2027 Notes at a fundamental change repurchase price equal to 100 % of the principal amount of the 2027 Notes to be repurchased plus accrued and unpaid interest. In addition, if specific corporate events occur prior to the maturity date or if we issue a notice of redemption, we will increase the conversion rate by pre-defined amounts for holders who elect to convert their notes in connection with such corporate event. In September 2025, concurrently with the pricing of the 2028 Notes, we entered into privately negotiated transactions with certain holders of the 2027 Notes to repurchase for cash $ 637.8 million aggregate principal amount of the outstanding 2027 Notes for a total repurchase cost (including accrued and unpaid interest of $ 3.1 million) of approximately $ 1.11 billion. The repurchase was accounted for as an induced conversion. We recorded an inducement expense of $ 39.1 million within loss related to convertible debt in the consolidated statements of operations and comprehensive income (loss) for the year ended December 31, 2025 and a charge to additional paid-in capital of $ 430.4 million within stockholders’ equity. In December 2025, we entered into privately negotiated transactions with certain holders of the 2027 Notes to repurchase for cash $ 34.4 million aggregate principal amount of the outstanding 2027 Notes for a total repurchase cost (including accrued and unpaid interest of $ 0.1 million) of approximately $ 52.3 million. The repurchase was accounted for as an induced conversion. We recorded an inducement expense of $ 3.3 million within loss related to convertible debt in the consolidated statements of operations and comprehensive income (loss) for the year ended December 31, 2025 and a charge to additional paid-in capital of $ 14.8 million within stockholders’ equity. As of June 30, 2026 and December 31, 2025, we had $ 362.8 million aggregate principal amount of the 2027 Notes outstanding. As of June 30, 2026 and December 31, 2025, the 2027 Notes were classified as a long-term liability on the condensed consolidated balance sheets and had a carrying value of $ 361.2 million and $ 360.5 million, respectively, representing outstanding principal amount net of unamortized issuance costs of $ 1.6 million and $ 2.3 million, respectively. The issuance costs are amortized to interest expense over the contractual term of the 2027 Notes. As of June 30, 2026 and December 31, 2025, the estimated fair value of the 2027 Notes was approximately $ 433.7 million and $ 534.1 million, respectively, which was determined based on the last actively traded price per $100 of the 2027 Notes (Level 2) on the respective dates. As of June 30, 2026 and December 31, 2025, the effective interest rate of the 2027 Notes was 1 %. 2022 Capped Call Transactions In 2022, in connection with the pricing of the 2027 Notes, we entered into privately negotiated capped call transactions, or 2022 Capped Call Transactions. The 2022 Capped Call Transactions initially cover, subject to customary anti-dilution adjustments, the number of shares of common stock that underlie the 2027 Notes. The cap price of the 2022 Capped Call Transactions is initially $ 424.00 per share, which represents a premium of 100 % over the last reported sale price of common stock of $ 212.00 per share on September 12, 2022, and is subject to certain adjustments under the terms of the 2022 Capped Call Transactions. As of June 30, 2026, the 2022 Capped Call Transactions remained outstanding. Because these transactions are indexed to our own stock and are considered equity classified, they were recorded in stockholders’ equity and are not accounted for as derivatives. The cost incurred to purchase the 2022 Capped Calls was recorded as a reduction to additional paid-in capital on our condensed consolidated balance sheets and the fair value of the capped call instrument is not remeasured each reporting period. Revolving Credit Agreement On September 30, 2025, we entered into the Revolving Credit Agreement, which provides for a $ 500.0 million revolving line of credit, including a $ 150.0 million sublimit for issuance of letters of credit. The Revolving Credit Agreement matures in September 2030, subject to earlier springing maturity under certain circumstances. 23 Table of Contents ALNYLAM PHARMACEUTICALS, INC. NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Unaudited) Borrowings, if any, will bear interest, at our option, at a base rate plus an applicable margin ranging from 0.50 % to 1.50 % based upon the total leverage ratio or a term Secured Overnight Financing Rate (or an alternative currency term rate) plus an applicable margin ranging from 1.50 % to 2.50 % based upon the total leverage ratio. We are required to pay, on a quarterly basis, a commitment fee ranging between 0.20 % to 0.35 % (depending on our total leverage ratio) of unused available commitments under the Revolving Credit Agreement. We are also obligated to pay the administrative agent fees customary for revolving credit facilities of this size and type. The Revolving Credit Agreement contains customary affirmative and negative covenants and conditions to borrowing, as well as customary events of default. In addition, the Revolving Credit Agreement contains financial covenants that require us to maintain a total leverage ratio less than or equal to 3.75 :1.00 and an interest coverage ratio greater than or equal to 3.00 :1.00, each tested at the end of each fiscal quarter. As of June 30, 2026, we were in compliance with the financial covenants. As of June 30, 2026 and December 31, 2025, we had no borrowings and $ 17.5 million of letters of credit outstanding under the Revolving Credit Agreement. 9. LIABILITIES RELATED TO THE SALE OF FUTURE ROYALTIES AND DEVELOPMENT FUNDING Development Funding Liabilities In August 2020, we entered into a co-development agreement, referred to as the Development Funding Agreement, with BXLS V Bodyguard – PCP L.P. and BXLS Family Investment Partnership V – ESC L.P., collectively referred to as Blackstone Life Sciences, pursuant to which Blackstone Life Sciences will provide up to $ 150.0 million in funding for the clinical development of vutrisiran and zilebesiran, two of our cardiometabolic programs. As of June 30, 2026, Blackstone Life Sciences has provided $ 70.0 million to fund vutrisiran development costs related to the HELIOS-B Phase 3 clinical trial and $ 26.0 million to fund Phase 2 clinical trials of zilebesiran. Additionally, Blackstone Life Sciences is obligated to fund $ 36.0 million for the Phase 3 clinical trial of zilebesiran following development milestones triggered in September 2025 and June 2026, of which $ 18.0 million has been provided as of June 30, 2026. The amount of funding ultimately provided by Blackstone Life Sciences for the Phase 3 clinical trial of zilebesiran is dependent on us achieving the remaining specified development milestones. As agreed between Blackstone Life Sciences and the Company, we retain sole responsibility for the development and commercialization of both vutrisiran and zilebesiran. As consideration for Blackstone Life Sciences’ funding for vutrisiran clinical development costs, we agreed to pay Blackstone Life Sciences $ 175.0 million triggered upon obtaining regulatory approval of vutrisiran for ATTR amyloidosis with cardiomyopathy, or ATTR-CM, and a 1.0 % royalty on net sales of vutrisiran for a 10-year term beginning upon the first commercial sale following regulatory approval of vutrisiran for ATTR-CM. In March 2025, we obtained a regulatory approval from the FDA for vutrisiran for ATTR-CM, triggering the $ 175.0 million payable to Blackstone Life Sciences in eight equal quarterly payments over two years . In September 2023, we announced positive topline results from the KARDIA-1 Phase 2 clinical trial of zilebesiran, triggering the achievement of the development milestone of $ 84.5 million payable to Blackstone Life Sciences in 16 equal quarterly payments over four years , as consideration for Blackstone Life Sciences’ funding for Phase 2 clinical development costs of zilebesiran. As consideration for funding for Phase 3 clinical development costs of zilebesiran, we agreed to pay Blackstone Life Sciences $ 243.0 million in 16 equal quarterly payments over four years triggered upon regulatory approval of zilebesiran in specified countries, unless it is later withdrawn from the market following a mandatory recall. Our payment obligations under the Development Funding Agreement are secured, subject to certain exceptions, by security interests in intellectual property owned by us relating to vutrisiran and zilebesiran, as well as in our bank account in which the funding deposits will be made. We and Blackstone Life Sciences each have the right to terminate the Development Funding Agreement in its entirety in the event of the other party’s bankruptcy or similar proceedings. We and Blackstone Life Sciences may each terminate the Development Funding Agreement in its entirety or with respect to either product in the event of an uncured material breach by the other party, or with respect to a product for certain patient health and safety reasons, or if regulatory approval in specified major market countries is not obtained for the product following the completion of clinical trials for the product. In addition, Blackstone Life Sciences has the right to terminate the Development Funding Agreement in its entirety upon the occurrence of certain events affecting our ability to make payments under the agreement or to develop or commercialize the products, or upon a change of control of us. Blackstone Life Sciences may also terminate the Development Funding Agreement with respect to a product if the joint steering committee elects to terminate the development program for that product in its entirety, if certain clinical endpoints are not achieved for that product or, with respect to vutrisiran only, if our right to develop or commercialize vutrisiran is enjoined in a specified major market as a result of an alleged patent infringement. In certain termination circumstances, we will be obligated to pay Blackstone Life Sciences an amount that is equal to, or a multiplier of, the development funding received from Blackstone Life Sciences, and we may remain obligated under certain circumstances to 24 Table of Contents ALNYLAM PHARMACEUTICALS, INC. NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Unaudited) make the payments to Blackstone Life Sciences described above should we obtain regulatory approval for zilebesiran following termination. The debt obligations to repay Blackstone Life Sciences for the vutrisiran and zilebesiran funding are accreted from the initial carrying amount to the total payment amount using the effective interest rate method over the life of the Development Funding Agreement. The effective interest rate is determined based on the proceeds received and projections of the amounts and timing of the future cash flows. The accretion is recorded as interest expense in the condensed consolidated statements of operations and comprehensive income (loss). We recognize the proceeds received and the principal portion of payments made to Blackstone Life Sciences as financing activities within the condensed consolidated statements of cash flows. As of June 30, 2026 and December 31, 2025, our estimates of total interest expense resulted in an effective annual interest rate of 51 % and 46 %, respectively, related to vutrisiran and 31 % and 32 %, respectively, related to zilebesiran. As payments are made to Blackstone Life Sciences, the balance of the liabilities is effectively repaid over the life of the Development Funding Agreement. The exact timing and amount of repayment is likely to change each reporting period. A significant increase or decrease in vutrisiran global net product revenues will materially impact the liability related to the vutrisiran payments and interest expense recognized. At each balance sheet date, we assess the expected payments to Blackstone Life Sciences and we prospectively adjust the amortization of the liabilities and the related interest expense. The following table shows the activity with respect to the vutrisiran development funding liability, in thousands: Carrying value as of December 31, 2025 $ 194,153 Interest expense 47,837 Amount paid ( 60,915 ) Carrying value as of June 30, 2026 $ 181,075 As of June 30, 2026 and December 31, 2025, we had $ 89.9 million and $ 94.5 million, respectively, within liabilities related to the sale of future royalties and development funding and $ 91.2 million and $ 99.7 million, respectively, within liabilities related to the sale of future royalties and development funding, net of current portion on our condensed consolidated balance sheets related to the vutrisiran development funding liability. The following table shows the activity with respect to the zilebesiran development funding liability, in thousands: Carrying value as of December 31, 2025 $ 17,047 Interest expense 3,810 Amount paid ( 10,562 ) Amount received 12,000 Carrying value as of June 30, 2026 $ 22,295 As of June 30, 2026 and December 31, 2025, we had $ 2.1 million and $ 6.8 million, respectively, within liabilities related to the sale of future royalties and development funding and $ 20.2 million and $ 10.3 million, respectively, within liabilities related to the sale of future royalties and development funding, net of current portion on our condensed consolidated balance sheets related to the zilebesiran development funding liability. The fair values of the vutrisiran and zilebesiran development funding liabilities were $ 555.3 million and $ 119.6 million, respectively, as of June 30, 2026, and $ 541.3 million and $ 116.2 million, respectively, as of December 31, 2025, based on our current estimates of future payments over the life of the arrangements and an estimated market participant weighted average cost of capital, which are considered Level 3 inputs. Liability Related to the Sale of Future Royalties In April 2020, we entered into a purchase and sale agreement, or Purchase Agreement, with BX Bodyguard Royalties L.P. (an affiliate of The Blackstone Group Inc.), or Blackstone Royalties, pursuant to which Blackstone Royalties acquired a percentage of royalties payable, or the Royalty Interest, initially set at 50 % with respect to net sales by MDCO, its affiliates or sublicensees of inclisiran (or the branded drug product, Leqvio) and any other licensed products under the MDCO License Agreement, and 75 % of the commercial milestone payments payable under the MDCO License Agreement, together with the Royalty Interest, the Purchased Interest. If Blackstone Royalties does not receive payments in respect to the Royalty Interest by 25 Table of Contents ALNYLAM PHARMACEUTICALS, INC. NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Unaudited) December 31, 2029, equaling at least $ 1.00 billion, Blackstone Royalties will receive the Royalty Interest at 55 % beginning on January 1, 2030. In consideration for the sale of the Purchased Interest, Blackstone Royalties paid us $ 1.00 billion. Due to our continuing involvement and an obligation to repay Blackstone Royalties, we recorded the proceeds from this transaction as a debt, net of closing costs, on our condensed consolidated balance sheets. The debt obligations to repay the Purchased Interest are accreted from the initial carrying amount to the total payment amount using the effective interest rate method over the life of the Purchase Agreement. The effective interest rate is determined based on the proceeds received and projections of the amounts and timing of the future cash flows. The accretion is recorded as interest expense in the condensed consolidated statements of operations and comprehensive income (loss). As of June 30, 2026 and December 31, 2025, our estimate of this total interest expense resulted in an effective annual interest rate of 14 % and 10 %, respectively. These estimates contain assumptions that impact both the amount recorded at execution and the interest expense that will be recognized in future periods. We account for any royalties and commercial milestones due to us under the MDCO License Agreement as revenue on our condensed consolidated statements of operations and comprehensive income (loss). As payments are made to Blackstone Royalties, the balance of the liability is effectively repaid over the life of the Purchase Agreement. The exact timing and amount of repayment is likely to change each reporting period. A significant increase or decrease in Leqvio global net revenue will materially impact the liability, interest expense and the time period for repayment. At each balance sheet date, we assess the expected payments to Blackstone Royalties and we prospectively adjust the amortization of the liability and the related interest expense. As of June 30, 2026 and December 31, 2025, the carrying value of the liability was $ 1.52 billion and $ 1.48 billion, net of closing costs of $ 7.9 million and $ 8.3 million, respectively. As of June 30, 2026 and December 31, 2025, the fair value of the liability was $ 1.96 billion and $ 1.61 billion, respectively, based on our current estimates of future payments over the life of the arrangements and an estimated market participant weighted average cost of capital, which are considered Level 3 inputs. The following table shows the activity with respect to the liability, in thousands: Carrying value as of December 31, 2025 $ 1,479,209 Interest expense 93,632 Payments ( 56,131 ) Carrying value as of June 30, 2026 $ 1,516,710 As of June 30, 2026 and December 31, 2025, we had $ 166.6 million and $ 118.8 million, respectively, within liabilities related to the sale of future royalties and development funding and $ 1.35 billion and $ 1.36 billion, respectively, within liabilities related to the sale of future royalties and development funding, net of current portion related to the Purchased Interest. 10. STOCK-BASED COMPENSATION The following table summarizes stock-based compensation expense included in operating costs and expenses on our condensed consolidated statements of operations and comprehensive income (loss), and stock-based compensation charges included in additional paid-in capital on our condensed consolidated statements of stockholders' equity: Three Months Ended June 30, Six Months Ended June 30, (In thousands) 2026 2025 2026 2025 Research and development $ 35,894 $ 49,552 $ 66,006 $ 73,350 Selling, general and administrative 50,731 62,128 90,773 95,042 Total stock-based compensation expense 86,625 111,680 156,779 168,392 Capitalized stock-based compensation costs 1,105 1,127 2,210 2,255 Total stock-based compensation charges $ 87,730 $ 112,807 $ 158,989 $ 170,647 11. NET INCOME (LOSS) PER COMMON SHARE We compute basic net income (loss) per common share by dividing net income (loss) by the weighted-average number of common shares outstanding. Diluted net income per common share utilizing the treasury stock and if-converted methods is based upon the weighted-average number of common shares and dilutive potential common share equivalents outstanding during the period. For periods in which we have generated a net loss, diluted net loss per common share is the same as basic net loss per common share, as the inclusion of potentially dilutive common shares would be anti-dilutive. 26 Table of Contents ALNYLAM PHARMACEUTICALS, INC. NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Unaudited) The following table sets forth the computation of basic and diluted net income (loss) per share: Three Months Ended June 30, Six Months Ended June 30, (In thousands, except per share amounts) 2026 2025 2026 2025 Net income (loss), as reported $ 164,494 $ ( 72,228 ) $ 370,485 $ ( 90,479 ) Adjustment for the elimination of interest expense on the convertible debt 2,392 — 4,766 — Net income (loss), for use in diluted income per share $ 166,886 $ ( 72,228 ) $ 375,251 $ ( 90,479 ) Weighted-average common shares — basic 133,606 130,628 133,244 130,155 Effect of dilutive securities: Convertible debt 2,255 — 2,255 — Options to purchase common stock, inclusive of performance-based stock options 1,634 — 1,756 — Restricted stock units, inclusive of performance-based restricted stock units 782 — 990 — Employee stock purchase program 4 — 4 — Weighted-average common shares — diluted 138,281 130,628 138,249 130,155 Net income (loss) per common share — basic $ 1.23 $ ( 0.55 ) $ 2.78 $ ( 0.70 ) Net income (loss) per common share — diluted $ 1.21 $ ( 0.55 ) $ 2.71 $ ( 0.70 ) The following table sets forth the potential weighted-average common shares excluded from the calculation of diluted net income (loss) per common share because their inclusion would be anti-dilutive: Three Months Ended June 30, Six Months Ended June 30, (In thousands) 2026 2025 2026 2025 Options to purchase common stock, inclusive of performance-based stock options 386 4,698 235 4,879 Unvested restricted stock units, inclusive of performance-based restricted stock units 734 2,762 405 2,583 Convertible debt — 3,616 — 3,616 Total 1,120 11,076 640 11,078 The effect of the 2022 Capped Call Transactions and 2025 Capped Call Transactions was also excluded from the calculation of diluted net income (loss) per share because exercise of these transactions would potentially reduce the number of shares of the Company’s common stock outstanding and, therefore, would be anti-dilutive. In the three and six months ended June 30, 2026, we excluded 8.5 million shares and in the three and six months ended June 30, 2025, we excluded 5.2 million shares related to these transactions. 12. COMMITMENTS AND CONTINGENCIES Technology License and Other Commitments We have licensed from third parties the rights to use certain technologies and information in our research processes as well as in any other products we may develop. In accordance with the related license or technology agreements, we are required to make certain fixed payments to the licensor or a designee of the licensor over various agreement terms. Many of these agreement terms are consistent with the remaining lives of the underlying intellectual property that we have licensed. As of June 30, 2026, our commitments over the next five years to make fixed and cancellable payments under existing license agreements were not material. Legal Matters From time to time, we may be a party to litigation, arbitration or other legal proceedings in the ordinary course of our business activities, including the following types of matters which are common to companies in our industry: 27 Table of Contents ALNYLAM PHARMACEUTICALS, INC. NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Unaudited) • Patent litigation, which typically involves challenges to the coverage and/or validity of patents on various products or product candidates, processes or dosage forms. An adverse outcome could result in loss of patent protection for a product or product candidates, a significant loss of revenues from a product or impairment of the value of associated assets. • Product liability and other product-related litigation related to our products, which could include personal injury, consumer fraud, off-label promotion, securities, antitrust and breach of contract claims, among others, and often involves highly complex issues relating to medical causation, label warnings and reliance on those warnings, scientific evidence and findings, actual, provable injury and other matters. • Commercial and other asserted or unasserted matters, which can include acquisition-, licensing-, intellectual property-, collaboration- or co-promotion-related and product-pricing claims and environmental claims and proceedings, which can involve complexities that will vary from matter to matter. • Government investigations, which often are related to the extensive regulation of pharmaceutical companies by national, state and local government agencies in the U.S. and in other jurisdictions. The outcome of any such legal proceedings, regardless of the merits, is inherently uncertain. In addition, litigation and related matters are costly and may divert the attention of our management and other resources that would otherwise be engaged in other activities. If we were unable to prevail in any such legal proceedings, it could have a materially adverse effect on our business, results of operations, liquidity and financial condition. If we determine that it is probable that future expenditures will be made for a particular matter and such expenditures can be reasonably estimated, we accrue a loss contingency based on our best estimate of the probable range of loss. We accrue the minimum amount within the probable range of loss if no amount within the range is more likely than another. If we determine that future expenditures are not probable, or probable but not reasonably estimated, we do not accrue a loss contingency. If we determine that a material loss is reasonably possible and the range of loss can be estimated, we disclose the possible range of loss. On a quarterly basis, we evaluate developments with these claims and legal proceedings that could result in a loss contingency accrual, or an increase or decrease to a previously accrued loss contingency. There were no material loss contingencies accrued as of June 30, 2026 or December 31, 2025. Patent Litigation On December 12, 2024, The Board of Regents of the University of Texas System filed a lawsuit in the U.S. District Court for the Western District of Texas, or the Texas District Court, alleging that we infringe U.S. Patent No. 8,895,717 by making, using and commercializing ONPATTRO in the U.S. On February 5, 2025, we filed a motion to dismiss the case for improper venue and an alternative motion to transfer the case to the U.S. District Court for the District of Massachusetts if the dismissal is not granted. On July 2, 2025, the Texas District Court denied the motion to dismiss and to transfer the case without prejudice, and we filed a renewed motion to dismiss and to transfer the case on September 24, 2025. On December 15, 2025, the court granted in part and denied in part our motion to dismiss and ordered the case transferred to the U.S. District Court for the District of Massachusetts after determining that venue was improper in the Western District of Texas. The case is now proceeding in the District of Massachusetts, and a claim construction hearing was held in July 2026. On March 13, 2026, we and our collaborators, Novartis Pharmaceuticals Corp., Novartis Technology LLC, and The Medicines Company, filed a patent infringement lawsuit against Cipla USA Inc. and Cipla Ltd, or collectively Cipla, in the U.S. District Court for the District of Delaware based on Cipla’s abbreviated new drug application seeking approval from the FDA to market a generic version of Leqvio ® (inclisiran). Government Investigation In October 2025, we received a subpoena from the U.S. Attorney’s Office for the District of Massachusetts seeking documents pertaining to our government price reporting for AMVUTTRA, ONPATTRO, OXLUMO and GIVLAARI, including certain fee and discount arrangements with distributors, and certain other related documents and communications. We have produced records responsive to the subpoena and are continuing to engage with the U.S. Attorney’s Office. Indemnification Obligations In connection with license agreements we may enter with companies to obtain rights to intellectual property, we may be required to indemnify such companies for certain damages arising in connection with the intellectual property rights licensed under the agreements. Under such agreements, we may be responsible for paying the costs of any litigation relating to the license agreements or the underlying intellectual property rights, including the costs associated with certain litigation regarding the licensed intellectual property. We are also a party to a number of agreements entered into in the ordinary course of business, which contain typical provisions that obligate us to indemnify the other parties to such agreements upon the occurrence of certain events, including litigation or other legal proceedings. In addition, we have agreed to indemnify our officers and 28 Table of Contents ALNYLAM PHARMACEUTICALS, INC. NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Unaudited) directors for expenses, judgments, fines, penalties, excise taxes, and settlement amounts paid in connection with any threatened, pending or completed litigation proceedings, in which an officer or director was, is or will be involved as a party, on account of such person’s status as an officer or director, or by reason of any action taken by the officer or director while acting in such capacity, subject to certain limitations. These indemnification costs are charged to selling, general and administrative expense. Our maximum potential future liability under any such indemnification provisions is uncertain. We have reviewed the estimated aggregate fair value of our potential liabilities under all such indemnification provisions and have not recorded any related liability as of June 30, 2026 or December 31, 2025. 13. SEGMENT INFORMATION We operate in a single segment dedicated to the discovery, development, manufacturing and commercialization of RNAi therapeutics. Consistent with our management reporting, results of our operations are reported on a consolidated basis for purposes of segment reporting. Our Chief Executive Officer, or CEO, as the chief operating decision maker, or CODM, evaluates performance and decides how to allocate resources based on consolidated net income (loss) that is reported on the condensed consolidated statements of operations and comprehensive income (loss). The measure of segment assets is reported on the condensed consolidated balance sheets as total assets. Please refer to the condensed consolidated financial statements for further information related to these measures of segment performance. In addition, research and development and selling, general and administrative expenses are significant segment expenses regularly provided to the CEO with the following categories: Research and Development Three Months Ended June 30, Six Months Ended June 30, (In thousands) 2026 2025 2026 2025 Clinical research and outside services $ 244,226 $ 140,692 $ 443,483 $ 268,035 Compensation and related 125,390 143,450 249,688 242,637 Occupancy and all other costs (1) 43,518 39,479 84,829 78,071 Total research and development expense $ 413,134 $ 323,621 $ 778,000 $ 588,743 Selling, General and Administrative Three Months Ended June 30, Six Months Ended June 30, (In thousands) 2026 2025 2026 2025 Compensation and related $ 166,619 $ 191,233 $ 329,696 $ 322,670 Consulting and professional services 120,721 82,637 225,898 147,324 Occupancy and all other costs (1) 60,582 49,444 114,879 93,269 Total selling, general and administrative expense $ 347,922 $ 323,314 $ 670,473 $ 563,263 (1) Occupancy and all other costs includes facilities, information technology, depreciation and certain departmental expenses . 29 Table of Contents ITEM 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS The following discussion contains management’s discussion and analysis of our financial condition and results of operations and should be read together with our unaudited condensed consolidated financial statements and the notes thereto included elsewhere in this Quarterly Report on Form 10-Q. Overview We are a global commercial-stage biopharmaceutical company developing novel therapeutics based on ribonucleic acid interference, or RNAi. RNAi is a naturally occurring biological pathway within cells for sequence-specific silencing and regulation of gene expression. By harnessing the RNAi pathway, we have pioneered a new class of innovative medicines, known as RNAi therapeutics. RNAi therapeutics are comprised of small interfering RNA, or siRNA, that function upstream of conventional medicines by potently silencing messenger RNA, or mRNA, that encode for proteins implicated in the cause or pathway of disease, thus preventing them from being made. We believe this is a revolutionary approach with the potential to transform the care of patients across a broad range of disease areas and indications. To date, our efforts to advance this revolutionary approach have yielded the approval of six first-in-class RNAi-based medicines: AMVUTTRA ® (vutrisiran), ONPATTRO ® (patisiran), GIVLAARI ® (givosiran), OXLUMO ® (lumasiran), Leqvio ® (inclisiran) and Qfitlia ® (fitusiran). Our research and development strategy is to target genetically validated genes that have been implicated in the cause or pathway of human disease. We utilize an N-acetylgalactosamine (GalNAc) conjugate approach or lipid nanoparticle (LNP) to enable hepatic delivery of siRNAs. For delivery to the central nervous system, or CNS, and the eye (ocular delivery), we are utilizing an alternative conjugate approach based on a hexadecyl (C16) moiety as a lipophilic ligand. We are also advancing approaches for heart, skeletal muscle and adipose tissue delivery of siRNAs, and we are exploring peptide and antibody-based approaches for targeted siRNA delivery to new tissues. Our focus is on clinical indications where there is a high unmet need, a genetically validated target, early biomarkers for the assessment of clinical activity in Phase 1 clinical trials, and a definable path for drug development, regulatory approval, patient access and commercialization. In early 2026, we launched our Alnylam 2030 strategy to drive our next era of growth and patient impact, and we currently have six marketed products, including two products that are commercialized by collaborators, and more than 25 clinical programs, including several in late-stage development. AMVUTTRA is approved in the United States, or U.S., for the treatment of hereditary transthyretin-mediated amyloidosis, or hATTR amyloidosis, with polyneuropathy in adults, in the European Union, or EU, and the United Kingdom, or UK, for the treatment of hATTR amyloidosis in adult patients with stage 1 or stage 2 polyneuropathy, in Japan for the treatment of transthyretin, or TTR, type familial amyloidosis with polyneuropathy, and in multiple additional countries. In March 2025, the United States Food and Drug Administration, or the FDA, approved our supplemental New Drug Application, or sNDA, for AMVUTTRA for the treatment of the cardiomyopathy of wild-type or hereditary transthyretin-mediated amyloidosis in adults to reduce cardiovascular mortality, cardiovascular hospitalizations and urgent heart failure visits. In June 2025, the European Commission, or EC, granted approval of AMVUTTRA for the treatment of wild-type or hereditary transthyretin amyloidosis in adult patients with cardiomyopathy, following a positive opinion from the Committee for Medicinal Products for Human Use of the European Medicines Agency. AMVUTTRA has also been approved by the Brazilian Health Regulatory Agency, or ANVISA, the Japanese Health Authority, or PMDA, the UK’s Medicines and Healthcare Products Regulatory Agency, or MHRA, and Health Canada for the treatment of ATTR amyloidosis with cardiomyopathy. Regulatory reviews continue in other territories. ONPATTRO is approved in the U.S. for the treatment of the polyneuropathy of hATTR amyloidosis in adults and is also approved in the EU for the treatment of hATTR amyloidosis in adult patients with stage 1 or stage 2 polyneuropathy, in Japan for the treatment of TTR-type familial amyloidosis with polyneuropathy, and in multiple additional countries. In February 2025, ONPATTRO received regulatory approval from ANVISA in Brazil for the treatment of ATTR amyloidosis with cardiomyopathy. GIVLAARI is approved in the U.S. for the treatment of adults with acute hepatic porphyria, or AHP, in the EU for the treatment of AHP in adults and adolescents aged 12 years and older, and in several other countries. Regulatory filings for givosiran (the generic name of GIVLAARI) in additional territories are pending or planned during 2026 and beyond. OXLUMO is approved in the U.S. for the treatment of primary hyperoxaluria type 1, or PH1, to lower urinary and plasma oxalate levels in pediatric and adult patients, and in the EU and the UK for the treatment of PH1 in all age groups. OXLUMO has also been approved in several other countries and regulatory filings for lumasiran (the generic name of OXLUMO) in additional territories are pending or planned during 2026 and beyond. Leqvio (inclisiran) is being developed and commercialized by our collaborator Novartis AG, or Novartis, and has received marketing authorization from the EC for the treatment of adults with hypercholesterolemia or mixed dyslipidemia and from the FDA as an adjunct to diet and exercise to reduce low-density lipoprotein cholesterol, or LDL-C, in adults with hypercholesterolemia, adults and pediatric patients aged 12 years and older with heterozygous familial hypercholesterolemia, or HeFH, and pediatric patients aged 12 years and older with homozygous familial hypercholesterolemia. Leqvio has also been 30 Table of Contents approved in China and Japan, and as of the end of June 2026, Leqvio is registered in 109 countries worldwide and is commercially available in 89 countries. Qfitlia (fitusiran) is being commercialized by our collaborator, Genzyme Corporation, a Sanofi Company, or Sanofi, and was approved by the FDA in March 2025 for routine prophylaxis to prevent or reduce the frequency of bleeding episodes in adult and pediatric patients 12 years of age and older with hemophilia A or B, with or without factor VIII or IX inhibitors (neutralizing antibodies), and by China’s National Medical Products Administration in December 2025, for routine prophylaxis to prevent or reduce the frequency of bleeding episodes in pediatric patients 12 years of age and older, and adults with severe hemophilia A with or without factor VIII inhibitors or severe hemophilia B with or without factor IX inhibitors. Qfitlia is the first and only therapeutic designed to lower antithrombin, a protein that inhibits blood clotting, with the goal of promoting thrombin generation to rebalance hemostasis and prevent bleeds. In addition to our marketed products, we have multiple potential drivers of future growth, including additional transformative medicines currently in development for TTR and both other rare and prevalent diseases. We are advancing nucresiran, our next-generation investigational RNAi therapeutic in development for the treatment of ATTR amyloidosis. In November 2024, we announced positive results from the ongoing Phase 1 clinical trial of nucresiran in healthy volunteers. These results demonstrated that twice annual dosing of 300 mg of nucresiran resulted in mean reductions of serum TTR of greater than 90% from baseline at day 15 that were maintained over six months. In September 2025, we initiated the TRITON-PN Phase 3 clinical trial of nucresiran in patients with hATTR polyneuropathy, and in June 2025, we initiated the TRITON-CM Phase 3 clinical trial of nucresiran in patients with ATTR amyloidosis with cardiomyopathy. In April 2026, we announced that, due to enrollment in TRITON-CM proceeding faster than anticipated, we exercised a pre-specified protocol option to expand target enrollment by approximately 500 patients, or from 1,250 to approximately 1,750 patients in total. Given the current pace of enrollment and the anticipated accrual of endpoint events, we continue to expect to launch nucresiran in ATTR-CM by 2030, assuming positive data and regulatory approval. We are developing zilebesiran, an investigational, subcutaneously administered RNAi therapeutic targeting angiotensinogen, for the treatment of hypertension. In 2023, we entered into a Collaboration and License Agreement, or the Roche Collaboration and License Agreement, with F. Hoffmann-La Roche Ltd. and Genentech, Inc. or, collectively, Roche, pursuant to which we established a worldwide, strategic collaboration for the joint development and commercialization of zilebesiran. In August 2025, we reported that our KARDIA-3 Phase 2 clinical trial, which was designed to evaluate the efficacy and safety of zilebesiran as an add-on therapy in adult patients with high cardiovascular risk and uncontrolled hypertension despite treatment with two to four standard of care antihypertensive medications, met the objective of informing the design, patient population, and dose for a global Phase 3 cardiovascular outcomes trial. In September 2025, we initiated a Phase 3 cardiovascular outcomes clinical trial, ZENITH (ZilebEsiraN CardIovascular OuTcome Study in Hypertension), which is designed to evaluate the potential of zilebesiran to reduce the risk of major adverse cardiovascular events in patients with uncontrolled hypertension on two or more antihypertensives, one being a diuretic. We are advancing mivelsiran (formerly ALN-APP), an investigational RNAi therapeutic targeting amyloid precursor protein in development for the treatment of cerebral amyloid angiopathy, or CAA, and Alzheimer’s disease, or AD. In July 2025, we presented single- and multiple-dose data from the Phase 1 clinical trial of mivelsiran in patients with early-onset AD. These data demonstrated that single and multiple doses of mivelsiran were generally well tolerated and demonstrated robust, durable, dose-dependent reductions of soluble amyloid precursor protein beta, or sAPPβ, in cerebrospinal fluid. In July 2025, we presented an analysis of safety data from single and multiple doses of mivelsiran in the Phase 1 clinical trial showing no evidence of increased risk of amyloid-related imaging abnormality events. In July 2024, we initiated the cAPPricorn-1 Phase 2 clinical trial of mivelsiran in patients with CAA and in July 2026, we announced that we had completed enrollment in this trial. In July 2026, we announced the initiation of a Phase 2 clinical trial of mivelsiran in patients with Down syndrome-associated AD. We are developing ALN-6400, a GalNAc-conjugated RNAi therapeutic that targets plasminogen, or PLG, for the treatment of a wide range of bleeding disorders. In preclinical studies, ALN-6400 demonstrated a greater than 90% reduction in circulating PLG in non-human primates with no evidence of increased risk of thrombosis. In early 2025, we shared data from the first cohort of participants in a Phase 1 clinical trial in healthy volunteers, demonstrating favorable impact on an ex-vivo hemostasis assay. In late 2025, we initiated a Phase 2 clinical trial of ALN-6400 in patients with Hereditary Hemorrhagic Telangiectasia, or HHT, and we plan to share additional data from the Phase 1 clinical trial as well as initial results in the Phase 2 clinical trial in HHT the second half of 2026. We also initiated a Phase 2 clinical trial of ALN-6400 in patients with von Willebrand Disease in the first half of 2026. We are advancing ALN-HTT02, an investigational, intrathecally administered RNAi therapeutic targeting huntingtin, or HTT, that is in development in collaboration with Regeneron Pharmaceuticals, Inc., or Regeneron, for the treatment of Huntington’s Disease, or HD. ALN-HTT02 is designed to target a conserved sequence in exon 1 of the HTT messenger RNA, thereby reducing the expression of all isoforms of HTT protein, including the shorter HTT1a isoform encoded by the first exon of the gene. In 2024 and 2025, we presented nonclinical data supporting the tolerability of deep and sustained HTT-lowering in wild-type nonhuman primates after single and repeated intrathecal administration of ALN-HTT02. In October 2025, we 31 Table of Contents initiated a Phase 1b clinical trial of ALN-HTT02 in adult patients with HD and expect to present initial data from this trial in the second half of 2026. We have additional late-stage investigational programs advancing toward potential commercialization with collaborators, including cemdisiran for the treatment of complement-mediated diseases. Our collaborator, Regeneron, is advancing cemdisiran in combination with its anti-C5 monoclonal antibody, pozelimab, in a Phase 3 clinical trial in paroxysmal nocturnal hemoglobinuria, and as a monotherapy and in combination with pozelimab in Phase 3 clinical trials in myasthenia gravis and geographic atrophy. In August 2025, Regeneron announced that cemdisiran monotherapy met the primary and key secondary endpoints in the Phase 3 NIMBLE clinical trial in generalized myasthenia gravis and in April 2026, Regeneron filed a New Drug Application, or NDA, for cemdisiran monotherapy with the FDA, which was accepted for review in June 2026 with a target action date of November 2026, following use of a Priority Review Voucher. A corresponding application was also accepted for review by the European Medicines Agency, or EMA, with a decision from the EC anticipated in the second half of 2027. We achieved profitability for the first time in 2025. Nevertheless, we have incurred significant losses since inception, and as of June 30, 2026, we had an accumulated deficit of $6.33 billion. Historically, we generated losses primarily from costs associated with research and development activities; acquiring, filing and protecting our intellectual property rights; and selling, general and administrative activities. With the achievement of profitability in 2025, going forward we expect to be able to fund our operations primarily from product revenues, which we expect will be supplemented by collaboration revenue and royalty revenue from products commercialized by our collaborators. We expect to continue investing significantly in research and development to advance our RNAi platform and clinical pipeline. These planned expenditures include costs associated with our activities as we (i) progress our late-stage programs, including the Phase 3 TRITON-PN and TRITON-CM clinical trials of nucresiran (our next generation TTR silencer) in patients with hATTR-PN and ATTR-CM, respectively, and the Phase 3 ZENITH cardiovascular outcomes trial of zilebesiran in patients with uncontrolled hypertension, all three of which we initiated in 2025; (ii) progress our early stage clinical pipeline, including CNS and metabolic programs; (iii) continue our efforts to deliver RNAi therapeutics to additional tissues and to treat new disease areas; and (iv) selectively pursue complementary modalities through business development. Through these investments, we plan to expand our efforts to discover, develop and commercialize the next wave of RNAi therapeutics and aim to achieve the goals associated with our Alnylam 2030 strategy. These goals include expanding to 10 tissue types and more than 40 clinical programs, delivering at least two new transformative medicines beyond TTR with blockbuster potential, investing approximately 30% of our revenues in non-GAAP R&D (including select external innovation), achieving 25%+ total revenue compound annual growth rate, and delivering approximately 30% non-GAAP operating margin through year-end 2030. As of June 30, 2026, we generate worldwide product revenues from our four commercialized products, AMVUTTRA, ONPATTRO, GIVLAARI and OXLUMO, primarily in the U.S. and Europe. Collaboration and royalty revenues, in particular from our collaborations with Roche, Regeneron and Novartis, have also represented a meaningful portion of our total revenues in recent years. We expect our sources of potential funding for the next several years to be derived primarily from sales of our commercialized products, with contributions from our existing collaborations, including royalties on sales of Leqvio by Novartis and on sales of Qfitlia by Sanofi, and any new strategic collaborations that we may enter in the future. However, we and our collaborators may not be able to successfully market and sell our existing commercialized products or any approved products in the future. Moreover, our ongoing development and regulatory efforts may not be successful, and we and our collaborators may not be able to commence sales of any other products in the future. We anticipate that our operating results will continue to fluctuate for the foreseeable future, and therefore, period-to-period comparisons should not be relied upon as predictive of the results in future periods. Given the significant and growing contribution of AMVUTTRA to our total product revenues following regulatory approvals of AMVUTTRA for the treatment of ATTR-CM, our cost of goods sold, operating income and operating margin have been significantly impacted by the royalties we pay to Sanofi on global sales of AMVUTTRA, and we expect this will continue in future years. Under our license agreement with Sanofi, Sanofi is eligible to receive tiered royalties on global annual net sales of AMVUTTRA across all indications in the following tiers: 15% of global annual net sales of $0 to $150.0 million; 17.5% of global annual net sales greater than $150.0 million to $300.0 million; 20% of global annual net sales greater than $300.0 million to $500.0 million; 25% of global annual net sales greater than $500.0 million to $1.50 billion; and 30% of global annual net sales in excess of $1.50 billion. There are no royalties owed on nucresiran, our next-generation investigational RNAi therapeutic, which is currently in development for the treatment of ATTR amyloidosis. Assuming successful development and regulatory approval, we believe that with its anticipated product profile, nucresiran has the potential to become a leading therapy for ATTR amyloidosis and to significantly improve our gross margins on product sales and operating income margin. Convertible Senior Notes and Repurchases In September 2025, we issued $661.3 million aggregate principal amount of 0.00% Convertible Senior Notes due 2028, or the 2028 Notes. The 2028 Notes will mature on September 15, 2028, unless earlier converted, redeemed or repurchased. The 2028 Notes will not bear regular interest. Before June 15, 2028, holders of 2028 Notes will have the right to convert their 2028 32 Table of Contents Notes in certain circumstances and during specified periods. From and after June 15, 2028, the 2028 Notes will be convertible at the option of the holders of 2028 Notes at any time prior to the close of business on the second scheduled trading day immediately preceding the maturity date. We will settle any conversions of 2028 Notes by paying or delivering, as applicable, cash or shares of our common stock, par value $0.01 per share, or Common Stock, or a combination of cash and shares of Common Stock, at our election. In connection with the issuance of the 2028 Notes, we paid $35.3 million, including expenses to enter into privately negotiated capped call transactions with certain initial purchasers of the 2028 Notes or their respective affiliates and certain other financial institutions, or capped call transactions. The capped call transactions are expected generally to reduce the potential dilution upon conversion of the 2028 Notes in the event that the market price per share of our Common Stock, as measured under the terms of the capped call transactions, is greater than the strike price of the capped call transactions, which initially corresponds to the conversion price of the 2028 Notes, and is subject to anti-dilution adjustments generally similar to those applicable to the conversion rate of the 2028 Notes. The initial cap price of the capped call transaction is approximately $837.61 per share, and is subject to certain adjustments under the terms of the capped call transactions. Concurrently with the pricing of the 2028 Notes, we entered into privately negotiated transactions, or the September 2025 note repurchase transactions, with certain holders of our 1.00% Convertible Senior Notes due 2027, or the 2027 Notes, to repurchase for cash approximately $637.8 million aggregate principal amount of the 2027 Notes for a total repurchase cost (including accrued and unpaid interest) of approximately $1.11 billion. In addition, in December 2025, we entered into additional privately negotiated transactions, or the December 2025 note repurchase transactions, with certain holders of our 2027 Notes to repurchase for cash approximately $34.4 million aggregate principal amount of the 2027 Notes for a total repurchase cost (including accrued and unpaid interest) of approximately $52.3 million. Following the closing of the December 2025 note repurchase transactions, or, together with the September 2025 note repurchase transactions, the note repurchase transactions, approximately $362.8 million aggregate principal amount of the 2027 Notes remain outstanding. We had previously entered into capped call transactions with certain financial institutions in connection with the issuance of the 2027 Notes, which transactions remain in place following the note repurchase transactions. Revolving Credit Facility In September 2025, we entered into a revolving credit agreement, or the Revolving Credit Agreement, among the lenders party thereto, Bank of America, N.A., as Administrative Agent, or the Agent, and the other parties named therein. The Revolving Credit Agreement provides for a $500.0 million revolving line of credit, or the Revolving Credit Facility, including a $150.0 million letter of credit sublimit. The Revolving Credit Agreement provides that we have the right at any time and from time to time to incur one or more incremental revolving commitments and/or incremental term loans, subject to certain customary conditions and other requirements. At our option, and subject to certain conditions, borrowings bear interest at a base rate, a term Secured Overnight Financing Rate, or SOFR, rate or an alternative currency term rate, plus, in each case, an applicable margin based upon our Total Leverage Ratio (as defined in the Revolving Credit Agreement). For borrowings that bear interest at a term SOFR rate, the applicable margin is a per annum amount equal to an amount between 1.50% and 2.50% (depending on our Total Leverage Ratio). Interest is payable quarterly in arrears with respect to borrowings bearing interest at the alternate base rate or on the last day of an interest period, but at least every three months, with respect to borrowings bearing interest at a term SOFR rate or an alternative currency term rate. We are also required to pay on a quarterly basis a commitment fee in a per annum amount equal to an amount between 0.20% to 0.35% (depending on our Total Leverage Ratio) of unused available commitments under the Revolving Credit Facility. We are also obligated to pay the Agent fees customary for revolving credit facilities of this size and type. The obligations under the Revolving Credit Agreement are required to be guaranteed by certain of our material domestic subsidiaries and are secured by substantially all of our assets and the assets of such subsidiary guarantors, subject to customary exceptions. The Revolving Credit Agreement contains customary affirmative and negative covenants and conditions to borrowing, as well as customary events of default. Revolving loans under the Revolving Credit Agreement may be borrowed, repaid and reborrowed, without premium or penalty (subject to customary breakage costs), until their maturity date under the Revolving Credit Agreement, or the Maturity Date, at which time all amounts borrowed must be repaid. The Maturity Date is currently September 30, 2030, but may be adjusted to an earlier date upon the occurrence of certain events in accordance with the terms of the Revolving Credit Agreement. Research and Development Since our inception, we have focused primarily on drug discovery and development programs. Research and development expenses represent a substantial percentage of our total operating expenses, as reflected by our broad pipeline of clinical development programs, which includes multiple programs in late-stage development. Our Product Pipeline 33 Table of Contents Our broad pipeline includes six approved products and multiple late and early-stage investigational RNAi therapeutics across a broad range of disease areas and indications. We describe our commercial and clinical-stage pipeline in more detail below. The clinical-stage therapeutics described below are in various stages of clinical development and the scientific information included about these therapeutics is preliminary and investigative. These clinical-stage therapeutics have not been approved by the FDA, EMA, or any other health authority and no conclusions can or should be drawn regarding the safety or efficacy of these investigational therapeutics. The table below represents our commercial products and late- and early-stage development programs as of July 30, 2026. 34 Table of Contents