SEC EDGAR · 10-Q

10-Q – 2025-10-30 – alny-20250930.htm

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44,755 41,886 | Deferred revenue 2,541 55,481 | Liability related to the sale of future royalties 115,691 113,018
Net revenues from collaborations 351,742 57,387 512,423 403,273 | Royalty revenue 46,202 23,386 112,649 56,407 | Total revenues 1,249,026 500,919 2,616,904 1,655,077
Accounts payable, accrued expenses and other liabilities 249,920 153,200 | Deferred revenue ( 52,940 ) ( 222,636 ) | Net cash provided by operating activities 360,525 86,350
Purchases of marketable securities ( 1,069,170 ) ( 1,148,203 ) | Sales and maturities of marketable securities 1,580,220 1,128,656 | Proceeds from maturity of restricted investments 59,775 57,875
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 an | Liquidity
Recent Accounting Pronouncements | In September 2025, the Financial Accounting Standards Board, or FASB, issued 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 . The guidance refines the scope of Topic 815 to clarify which contracts are subject to derivative accounting. The guidance also provides clarification under Topic 606 for share-based payments from a customer in a revenue contract. The standard wi | In September 2025, the 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.
As of September 30, 2025 and December 31, 2024, net product revenue-related receivables of $ 572.8 million and $ 269.9 million, respectively, were included in accounts receivable, net on our condensed consolidated balance sheets. | 12
The following table summarizes balances and activity in each product revenue allowance and reserve category:

Periodens resultat

Benefit from (provision for) income taxes 12,115 ( 2,907 ) ( 34,687 ) ( 10,977 ) | Net income (loss) $ 251,084 $ ( 111,570 ) $ 127,328 $ ( 194,394 )
Net income (loss) per common share — basic $ 1.91 $ ( 0.87 ) $ 0.98 $ ( 1.53 ) | Net income (loss) per common share — diluted $ 1.84 $ ( 0.87 ) $ 0.95 $ ( 1.53 )
Statements of Comprehensive Income (Loss) | Net income (loss) $ 251,084 $ ( 111,570 ) $ 127,328 $ ( 194,394 ) | Other comprehensive income:
Other comprehensive income — — — 8,177 — 8,177 | Net income — — — — 251,084 251,084 | Balance as of September 30, 2025 131,791 $ 1,318 $ 7,414,771 $ ( 21,775 ) $ ( 7,160,420 ) $ 233,894
Cash flows from operating activities: | Net income (loss) $ 127,328 $ ( 194,394 ) | Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Net income (loss) $ 127,328 $ ( 194,394 ) | Adjustments to reconcile net income (loss) to net cash provided by operating activities: | Depreciation and amortization 42,152 42,502
12. 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 sha
12. 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 sha | 25

Resultat per aktie

The accounting method for convertible debt securities that may be settled in cash, such as the Notes, could have a material effect on our reported financial results. | The accounting method for reflecting the Notes on our condensed consolidated balance sheet, accruing interest expense for the Notes and reflecting the underlying shares of our common stock in our reported diluted earnings per share may adversely affect our reported earnings and financial condition. | The Notes are reflected as a liability on our condensed consolidated balance sheets, with the initial carrying amount equal to the principal amount of the Notes, net of issuance costs. The issuance costs were treated as a debt discount for accounting purposes, which is being amortized into interest expense over the term of the Notes. As a result of this amortization, the interest expense that we expect to recognize for the Notes for accounting purposes will be greater than the cash interest paym
The Notes are reflected as a liability on our condensed consolidated balance sheets, with the initial carrying amount equal to the principal amount of the Notes, net of issuance costs. The issuance costs were treated as a debt discount for accounting purposes, which is being amortized into interest expense over the term of the Notes. As a result of this amortization, the interest expense that we expect to recognize for the Notes for accounting purposes will be greater than the cash interest paym | In addition, the shares of common stock underlying the Notes are reflected in our diluted earnings per share using the “if-converted” method, in accordance with ASU 2020-06. Under this method, diluted earnings per share is generally calculated assuming that all the Notes were converted solely into shares of common stock at the beginning of the reporting period, unless the result would be anti-dilutive. The application of the if-converted method may reduce our reported diluted earnings per share | 78

Kassaflöde

Liquidity and Capital Resources | The following table summarizes our cash flow activities:
Risks Related to Our Convertible Notes | • We may not have sufficient cash flow from our business to pay our indebtedness. | • We may not have the ability to raise the funds necessary to settle for cash conversions of our 2027 Notes, or to repurchase the 2027 Notes or our 2028 Notes and, together with the 2027 Notes, the Notes, for cash upon a fundamental change.
Risks Related to Our Convertible Notes | We may not have sufficient cash flow from our business to pay our indebtedness. | As of September 30, 2025, we had $397.2 million in total aggregate principal amount of Notes issued and outstanding. The interest rate for the 2027 Notes is fixed at 1.00% per annum and is payable semi-annually in arrears on March 15 and September 15 of each year. The 2028 Notes do not bear regular interest. Our ability to make scheduled payments of the principal of, to pay interest on or to refinance our indebtedness, including the Notes, or to make cash payments in connection with any conversi
We may not have sufficient cash flow from our business to pay our indebtedness. | As of September 30, 2025, we had $397.2 million in total aggregate principal amount of Notes issued and outstanding. The interest rate for the 2027 Notes is fixed at 1.00% per annum and is payable semi-annually in arrears on March 15 and September 15 of each year. The 2028 Notes do not bear regular interest. Our ability to make scheduled payments of the principal of, to pay interest on or to refinance our indebtedness, including the Notes, or to make cash payments in connection with any conversi | In addition, our indebtedness, combined with our other financial obligations and contractual commitments, could have other important consequences. For example, it could:

Likvida medel

Current assets: | Cash and cash equivalents $ 1,490,249 $ 966,428 | Marketable debt securities 1,234,375 1,719,920
Marketable debt securities $ 1,234,375 $ 1,719,920 | Cash and cash equivalents 25,024 69,089 | Total $ 1,259,399 $ 1,789,009
(In thousands) 2025 2024 | Cash and cash equivalents $ 1,490,249 $ 1,099,920 | Total restricted cash included in other assets 2,553 2,578

Nettoskuld

Net income (loss) $ 127,328 $ ( 194,394 ) | Adjustments to reconcile net income (loss) to net cash provided by operating activities: | Depreciation and amortization 42,152 42,502
Deferred revenue ( 52,940 ) ( 222,636 ) | Net cash provided by operating activities 360,525 86,350 | Cash flows from investing activities:
Other investing activities ( 2,150 ) — | Net cash provided by (used in) investing activities 473,495 ( 63,930 ) | Cash flows from financing activities:
Net cash used in (provided by) financing activities ( 350,507 ) 263,162 | Effect of exchange rate changes on cash, cash equivalents and restricted cash 40,637 2,032
◦ Regeneron is planning a U.S. regulatory submission for cemdisiran monotherapy in the first quarter of 2026, pending discussions with the FDA. | There is a risk that any drug discovery or development program may not produce revenue for a variety of reasons, including the possibility that we will not be able to adequately demonstrate the safety and effectiveness of the product candidate or obtain approval or the desired labeling for the product candidate from regulatory authorities. The success of AMVUTTRA, ONPATTRO, GIVLAARI, OXLUMO or any other product candidate we develop is highly uncertain. Due to the numerous risks associated with d | Strategic Collaborations
(In thousands) 2025 2024 | Net cash provided by (used in): | Operating activities $ 360,525 $ 86,350
Operating activities | Net cash provided by operating activities increased during the nine months ended September 30, 2025, compared to the same period in 2024, primarily due to stronger cash receipts from increased product sales, partially offset by increased employee compensation and decreased cash received from our collaborators. | Investing activities
Investing activities | Net cash provided by (used in) investing activities increased during the nine months ended September 30, 2025, compared to the same period in 2024, primarily due to the timing of sales, maturities, and purchases of our marketable securities. | Financing activities

Eget kapital

CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY (DEFICIT) FOR THE THREE MONTHS ENDED SEPTEMBER 30, 2025 AND 2024 , THE THREE MONTHS ENDED JUNE 30, 2025 AND 2024, AND THE THREE MONTHS ENDED MARCH 31. 2025 AND 2024 | 7
Total assets $ 4,851,662 $ 4,239,983 | LIABILITIES AND STOCKHOLDERS' EQUITY | Current liabilities:
Stockholders' equity: | Preferred stock, $ 0.01 par value per share, 5,000 shares authorized and no shares issued and outstanding as of September 30, 2025 and December 31, 2024
Accumulated deficit ( 7,160,420 ) ( 7,287,748 ) | Total stockholders' equity 233,894 67,088 | Total liabilities and stockholders' equity $ 4,851,662 $ 4,239,983
Total stockholders' equity 233,894 67,088 | Total liabilities and stockholders' equity $ 4,851,662 $ 4,239,983
ALNYLAM PHARMACEUTICALS, INC. | CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY (DEFICIT) | (In thousands)
Paid-in | Capital Accumulated Other Comprehensive Loss Accumulated Deficit Total Stockholders' Equity | Shares Amount
stockholders’ equity and are not accounted for as derivatives. The $ 35.3 million cost incurred in connection with the 2025 Capped Call Transactions 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

Antal aktier

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 cap price of the 2025 Capped Call Transactions is initially $ 837.61 per share, which represents a premium of 75 % above the U.S. composite volume weighted average | 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
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 | Revolving Credit Agreement
12. 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 sha | 25
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 nine months ended September 30, 2025, we excluded 5.8 million shares and 5.4 million shares, respectively, and in the three and nine months ended September
In the past, securities class action litigation has often been brought against companies following declines in the market price of their securities. This risk is especially relevant for biopharmaceutical companies, which have experienced significant stock price volatility in recent years. We may be the target of securities litigation that could result in substantial costs and divert our management’s attention and resources, which could cause serious harm to our business, prospects, operating res | Sales of a substantial number of shares of our common stock, including by us, our officers or directors, or our significant stockholders, into the public market could cause the price of our common stock to decline. | A small number of our stockholders beneficially own a substantial amount of our common stock. As of September 30, 2025, our seven largest stockholders beneficially owned in excess of 50% of our outstanding shares of common stock. If we, our officers or directors, or our significant stockholders sell substantial amounts of our common stock in the public market, or there is a perception that such sales may occur, the market price of our common stock could be adversely affected. Sales of common sto
convert their notes, we may settle our conversion obligation by delivering to them a significant number of shares of our common stock, which would cause dilution to our existing stockholders. | In addition, in connection with the issuance of the Notes, we entered into the Capped Calls with certain financial institutions, or the Option Counterparties. The Capped Calls are generally expected to reduce potential dilution to our common stock upon any conversion or settlement of the Notes and/or offset any cash payments we are required to make in excess of the principal amount of converted Notes, with such reduction and/or offset subject to a cap.

Antal anställda

In March 2022, we filed separate lawsuits in the U.S. District Court for the District of Delaware, or the District Court, against (1) Moderna, Inc. and its subsidiaries ModernaTX, Inc. and Moderna US, Inc., collectively referred to as Moderna, which we refer to as the Moderna lawsuit, and (2) Pfizer Inc. and its subsidiary Pharmacia & Upjohn Co. LLC, collectively referred to as Pfizer, which we refer to as the Pfizer lawsuit, seeking damages for patent infringement in Moderna’s and Pfizer’s manu | On July 12, 2024, Acuitas Therapeutics, Inc., or Acuitas, filed a declaratory judgment action against us in the District Court, seeking a judgment adding certain Acuitas employees as co-inventors on the patents we have asserted against Pfizer/BioNTech and Moderna in our lawsuits. On September 19, 2024, we filed a motion to dismiss, arguing Acuitas did not have standing to sue and failed to state a claim upon which relief could be granted. On July 1, 2025, the District Court granted our motion to | 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
We have additional late-stage investigational programs advancing toward potential commercialization, including cemdisiran for the treatment of complement-mediated diseases, which our collaborator, Regeneron Pharmaceuticals, Inc., or Regeneron, is advancing in combination with pozelimab in Phase 3 clinical trials in myasthenia gravis, geographic atrophy and paroxysmal nocturnal hemoglobinuria. In August 2025, Regeneron announced that cemdisiran monotherapy met the primary and key secondary endpoi | In further support of our Alnylam P 5 x25 strategy and in view of our evolving risk profile, we remain focused on the continued evolution of our global infrastructure, including key objectives such as optimizing our global structure for execution in key markets, enhancing performance consistent with our values, and continuing to strengthen our culture. We continue to build our global compliance program to drive its evolution and enhancement through the launch of new systems and leveraging data a | 30
In addition to the manufacture of synthetic siRNAs, we may have additional manufacturing requirements related to the technology required to deliver the siRNA to the relevant cell or tissue type, such as LNPs or conjugates or other drug delivery technologies. In some cases, the delivery technology we utilize is specialized or proprietary, and for technical and/or legal reasons, we may have access to only one or a limited number of potential manufacturers for such delivery technology. In addition, | In developing manufacturing capabilities by building our own manufacturing facilities, we have incurred substantial expenditures, and expect to incur significant additional expenditures in the future. Also, we have had to, and will likely need to continue to, recruit, hire, and train qualified employees to staff our facilities. If we are unable to manufacture sufficient quantities of material or if we encounter problems with our facilities in the future, we may also need to secure alternative su | The manufacturing processes for our products and any other product candidates that we may develop is subject to the FDA and foreign regulatory authority approval processes and we will need to meet, and will need to contract with CMOs that can meet, all applicable FDA and foreign regulatory authority requirements on an ongoing basis. The failure of any CMO to meet required regulatory authority requirements could result in the delayed submission of regulatory applications, or delays in receiving r
We rely on third parties to conduct our clinical trials, and if such third parties fail to fulfill their obligations, our development plans may be adversely affected. | We rely on independent clinical investigators, CROs, and other third-party service providers to assist us in managing, monitoring and otherwise carrying out our clinical trials. We have contracted with, and we plan to continue to contract with, certain third parties to provide certain services for our clinical trials, including site selection, enrollment, monitoring, auditing and data management services. These investigators and CROs are not our employees, and we have limited control over the am | 51
If we are unable to attract and retain qualified key management and scientists, development, medical and commercial staff, consultants and advisors, our ability to implement our business plan may be adversely affected. | We are highly dependent upon our senior management and our scientific, clinical, sales and medical staff. The loss of the services of any members of our senior management could significantly delay or prevent the achievement of product development and commercialization, and other business objectives, and adversely impact our stock price. Our employment arrangements with our key personnel are terminable without notice. We do not carry key person life insurance on any of our employees. | We have grown our workforce significantly over the past several years and anticipate additional employee growth in the future, and we face intense competition for qualified individuals from numerous pharmaceutical and biotechnology companies, universities, governmental entities and other research institutions, many of which have substantially greater resources to attract and reward qualified individuals than we do. If we are not able to attract and retain highly qualified sales and marketing, re
We are increasingly dependent on our information technology systems and infrastructure for our business. We collect, store and transmit sensitive information including intellectual property, proprietary business information, including highly sensitive clinical trial data, and personal information in connection with our business operations. The secure maintenance of this information is critical to our operations and business strategy. Some of this information could be subject to information breac | The pervasiveness of cybersecurity incidents in general and the risks of cyber-crime are complex and continue to evolve. Although we are making significant efforts to maintain the security and integrity of our information systems and are exploring various measures to manage the risk of a security breach or disruption, there can be no assurance that our security efforts and measures will be effective or that attempted security breaches or disruptions would not be successful or damaging. Despite t | 53
several changes to the reach and oversight of the FDA, which could affect its relationship with the pharmaceutical industry, transparency in decision making and ultimately the cost and availability of prescription drugs. The FDA may pursue legislative, regulatory or policy changes regarding the standards or processes for approving our products or product candidates that we may be unable to satisfy. Additionally, over the last several years, the U.S. government has shut down multiple times and ce | The FDA or foreign regulatory authorities may request additional clinical or other data or information in connection with the regulatory review of our or our collaborators’ product candidates, including by issuing a complete response letter that may require that we or our collaborators submit additional clinical or other data or impose other conditions that must be met in order to secure final approval of our or our collaborators’ NDA applications, including potentially requiring a facility insp
We are subject to U.S. and certain foreign export and import controls, sanctions, embargoes, anti-corruption laws, and anti-money laundering laws and regulations. Failure to comply with these legal standards could impair our ability to compete in domestic and international markets. We can face criminal liability and other serious consequences for violations, which can harm our business. | We are subject to export control and import laws and regulations, including the U.S. Export Administration Regulations, U.S. Customs regulations, various economic and trade sanctions regulations administered by the U.S. Treasury Department’s Office of Foreign Assets Control, and anti-corruption laws, including the U.S. Foreign Corrupt Practices Act of 1977, as amended, the U.S. domestic bribery statute contained in 18 U.S.C. § 201, the U.S. Travel Act, the USA PATRIOT Act, the UK Bribery Act 201 | We remain focused on these laws and the activities they regulate and maintain a global compliance program designed to empower our business to operate in compliance with their requirements.

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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
____________________________________________
FORM 10-Q
____________________________________________
☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the quarterly period ended September 30, 2025
OR
☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the transition period from ___________ to ___________
Commission File Number 001-36407
__________________________________________
ALNYLAM PHARMACEUTICALS, INC.
(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 October 24, 2025, the registrant had 132,113,818 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 S EPTEMBER 30, 2025 AND DECEMBER 31, 202 4
5

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME ( LOSS ) FOR THE THREE AND NINE MONTHS ENDED SEPTEMBER 30, 2025 AND 202 4
6

CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY (DEFICIT) FOR THE THREE MONTHS ENDED SEPTEMBER 30, 2025 AND 2024 , THE THREE MONTHS ENDED JUNE 30, 2025 AND 2024, AND THE THREE MONTHS ENDED MARCH 31. 2025 AND 2024
7

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS FOR THE NINE MONTHS ENDED SEPTEMBER 30, 2025 AND 202 4
9

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS
10

ITEM 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS
29

ITEM 3. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK
42

ITEM 4. CONTROLS AND PROCEDURES
42

PART II.  OTHER INFORMATION

ITEM 1. LEGAL PROCEEDINGS
43

ITEM 1A. RISK FACTORS
43

ITEM 5. OTHER INFORMATION
79

ITEM 6. EXHIBITS
80

SIGNATURES
81

“Alnylam,” AMVUTTRA ® , ONPATTRO ® , GIVLAARI ® and OXLUMO ® 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,” “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 views with respect to the potential for 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 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;
• 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 ability to successfully execute on our Alnylam P 5 x25 strategy and our intention to achieve the metrics associated with this strategy, including to become a top-tier biotech company by the end of 2025;
• our ability to achieve sustainable operating profitability beginning in 2025;
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• 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 of 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 above 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.

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PART I. FINANCIAL INFORMATION
ITEM 1. FINANCIAL STATEMENTS ( UNAUDITED )

ALNYLAM PHARMACEUTICALS, INC.
CONDENSED CONSOLIDATED BALANCE SHEETS
(In thousands, except per share amounts)
(Unaudited)

September 30, 2025 December 31, 2024
ASSETS
Current assets:
Cash and cash equivalents $ 1,490,249   $ 966,428  
Marketable debt securities 1,234,375   1,719,920  
Marketable equity securities —   8,156  
Accounts receivable, net 964,768   405,308  
Inventory 75,383   78,509  
Prepaid expenses and other current assets 188,036   116,964  

Total current assets 3,952,811   3,295,285  
Property, plant and equipment, net 501,754   502,784  
Operating lease right-of-use assets 191,390   191,148  
Deferred tax assets
98,558   116,863  
Restricted investments 51,314   68,593  
Other assets 55,835   65,310  
Total assets $ 4,851,662   $ 4,239,983  
LIABILITIES AND STOCKHOLDERS' EQUITY
Current liabilities:
Accounts payable $ 117,591   $ 88,415  
Accrued expenses 1,153,648   793,692  
Operating lease liabilities
44,755   41,886  
Deferred revenue 2,541   55,481  
Liability related to the sale of future royalties 115,691   113,018  
Development derivative liability 121,251   93,780  
Total current liabilities 1,555,477   1,186,272  
Operating lease liabilities, net of current portion
223,421   229,541  

Convertible debt 1,040,276   1,024,621  
Liability related to the sale of future royalties, net of current portion 1,349,166   1,334,353  
Development derivative liability, net of current portion 439,659   393,139  
Other liabilities 9,769   4,969  
Total liabilities
4,617,768   4,172,895  
Commitments and contingencies (Note 13)

Stockholders' equity:
Preferred stock, $ 0.01 par value per share, 5,000 shares authorized and no shares issued and outstanding as of September 30, 2025 and December 31, 2024
—   —  
Common stock, $ 0.01 par value per share, 250,000 shares authorized; 131,791 shares issued and outstanding as of September 30, 2025; 129,294 shares issued and outstanding as of December 31, 2024
1,318   1,293  
Additional paid-in capital 7,414,771   7,388,061  
Accumulated other comprehensive loss ( 21,775 ) ( 34,518 )
Accumulated deficit ( 7,160,420 ) ( 7,287,748 )
Total stockholders' equity 233,894   67,088  
Total liabilities and stockholders' equity $ 4,851,662   $ 4,239,983  

The accompanying notes are an integral part of these condensed consolidated financial statements.
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ALNYLAM PHARMACEUTICALS, INC.
CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME (LOSS)
(In thousands, except per share amounts)
(Unaudited)

Three Months Ended
September 30, Nine Months Ended
September 30,
2025 2024 2025 2024
Statements of Operations
Revenues:
Net product revenues $ 851,082   $ 420,146   $ 1,991,832   $ 1,195,397  
Net revenues from collaborations 351,742   57,387   512,423   403,273  
Royalty revenue 46,202   23,386   112,649   56,407  
Total revenues 1,249,026   500,919   2,616,904   1,655,077  
Operating costs and expenses:
Cost of goods sold 197,231   81,980   409,443   203,864  
Cost of collaborations and royalties 2,923   3,925   4,705   16,689  
Research and development 358,814   270,926   947,557   826,063  
Selling, general and administrative 322,076   220,993   885,339   680,187  
Total operating costs and expenses 881,044   577,824   2,247,044   1,726,803  
Income (loss) from operations 367,982   ( 76,905 ) 369,860   ( 71,726 )
Other (expense) income:

Interest expense ( 44,398 ) ( 34,376 ) ( 123,290 ) ( 102,887 )
Interest income 28,681   32,146   84,840   90,973  
Loss related to convertible debt
( 39,146 ) —   ( 39,146 ) —  
Other expense, net ( 74,150 ) ( 29,528 ) ( 130,249 ) ( 99,777 )
Total other expense, net ( 129,013 ) ( 31,758 ) ( 207,845 ) ( 111,691 )
Income (loss) before income taxes 238,969   ( 108,663 ) 162,015   ( 183,417 )
Benefit from (provision for) income taxes 12,115   ( 2,907 ) ( 34,687 ) ( 10,977 )
Net income (loss) $ 251,084   $ ( 111,570 ) $ 127,328   $ ( 194,394 )

Net income (loss) per common share — basic $ 1.91   $ ( 0.87 ) $ 0.98   $ ( 1.53 )
Net income (loss) per common share — diluted $ 1.84   $ ( 0.87 ) $ 0.95   $ ( 1.53 )

Weighted-average common shares — basic
131,447   128,590   130,590   127,159  
Weighted-average common shares — diluted 137,348   128,590   134,146   127,159  

Statements of Comprehensive Income (Loss)
Net income (loss) $ 251,084   $ ( 111,570 ) $ 127,328   $ ( 194,394 )
Other comprehensive income:
Unrealized gains on marketable securities 1,131   9,078   1,818   4,783  
 Foreign currency translation gains (losses) 6,993   703   10,764   ( 6,327 )
Defined benefit pension plans, net of tax 53   30   161   93  
Total other comprehensive income (loss) 8,177   9,811   12,743   ( 1,451 )
Comprehensive income (loss) $ 259,261   $ ( 101,759 ) $ 140,071   $ ( 195,845 )

The accompanying notes are an integral part of these condensed consolidated financial statements.
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ALNYLAM PHARMACEUTICALS, INC.
CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY (DEFICIT)
(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  
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 —  —  —  —  ( 57,479 ) ( 57,479 )
Balance as of March 31, 2025 130,311   1,303   7,496,876   ( 37,517 ) ( 7,345,227 ) 115,435  
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 —  —  —  —  ( 66,277 ) ( 66,277 )
Balance as of June 30, 2025 130,977   1,310   7,690,737   ( 29,952 ) ( 7,411,504 ) 250,591  
Exercise of common stock options, net of tax withholdings 625   6   80,414   —  —  80,420  
Issuance of common stock under equity plans 189   2   ( 2 ) —  —  —  
Stock-based compensation —  —  109,339   —  —  109,339  
Repurchase of 1.00 % Convertible Senior Notes due 2027
—  —  ( 430,406 ) —  —  ( 430,406 )
Purchase of capped calls related to 0.00 % Convertible Senior Notes due 2028
—  —  ( 35,311 ) —  —  ( 35,311 )
Other comprehensive income —  —  —  8,177   —  8,177  
Net income —  —  —  —  251,084   251,084  
Balance as of September 30, 2025 131,791   $ 1,318   $ 7,414,771   $ ( 21,775 ) $ ( 7,160,420 ) $ 233,894  

The accompanying notes are an integral part of these condensed consolidated financial statements.
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ALNYLAM PHARMACEUTICALS, INC.
CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY (DEFICIT)
(In thousands)
(Unaudited)

Common Stock Additional
Paid-in
Capital Accumulated
Other
Comprehensive
Loss
Accumulated
Deficit Total
Stockholders’
(Deficit) Equity

Shares Amount
Balance as of December 31, 2023 125,794   $ 1,259   $ 6,811,063   $ ( 23,375 ) $ ( 7,009,591 ) $ ( 220,644 )
Exercise of common stock options, net of tax withholdings 223   2   24,763   —  —  24,765  
Issuance of common stock under equity plans 446   4   ( 4 ) —  —  —  
Stock-based compensation —  —  46,155   —  —  46,155  
Other comprehensive loss —  —  —  ( 3,613 ) —  ( 3,613 )
Net loss —  —  —  —  ( 65,935 ) ( 65,935 )
Balance as of March 31, 2024 126,463   1,265   6,881,977   ( 26,988 ) ( 7,075,526 ) ( 219,272 )
Exercise of common stock options, net of tax withholdings 1,264   13   140,273   —  —  140,286  
Issuance of common stock under equity plans 294   3   10,358   —  —  10,361  
Stock-based compensation —  —  90,096   —  —  90,096  
Other comprehensive loss —  —  —  ( 7,649 ) —  ( 7,649 )
Net loss —  —  —  —  ( 16,889 ) ( 16,889 )
Balance as of June 30, 2024 128,021   1,281   7,122,704   ( 34,637 ) ( 7,092,415 ) ( 3,067 )
Exercise of common stock options, net of tax withholdings 785   8   90,560   —  —  90,568  
Issuance of common stock under equity plans 35   —   —   —  —  —  
Stock-based compensation —  —  46,612   —  —  46,612  

Other comprehensive income —  —  —  9,811   —  9,811  
Net loss —  —  —  —  ( 111,570 ) ( 111,570 )
Balance as of September 30, 2024 128,841   $ 1,289   $ 7,259,876   $ ( 24,826 ) $ ( 7,203,985 ) $ 32,354  

The accompanying notes are an integral part of these condensed consolidated financial statements.
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ALNYLAM PHARMACEUTICALS, INC.
CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS
(In thousands)
(Unaudited)

Nine Months Ended September 30,
2025 2024
Cash flows from operating activities:
Net income (loss) $ 127,328   $ ( 194,394 )
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization 42,152   42,502  
Non-cash interest expense on liability related to the sale of future royalties 112,298   91,834  
Stock-based compensation expense
276,603   180,439  
Realized and unrealized loss on marketable equity securities
2,306   2,856  
Loss on extinguishment of debt 39,146   —  
Change in fair value of development derivative liability 138,813   100,499  
Deferred income taxes
24,972   631  
Other ( 31,464 ) ( 32,228 )
Changes in operating assets and liabilities:
Accounts receivable, net ( 544,210 ) ( 27,042 )
Inventory 22,335   12,741  
Prepaid expenses and other assets ( 46,734 ) ( 22,052 )
Accounts payable, accrued expenses and other liabilities 249,920   153,200  
Deferred revenue ( 52,940 ) ( 222,636 )
Net cash provided by operating activities 360,525   86,350  
Cash flows from investing activities:
Purchases of property, plant and equipment ( 35,405 ) ( 25,183 )
Purchases of marketable securities ( 1,069,170 ) ( 1,148,203 )
Sales and maturities of marketable securities 1,580,220   1,128,656  
Proceeds from maturity of restricted investments 59,775   57,875  
Purchases of restricted investments ( 59,775 ) ( 77,075 )
Other investing activities ( 2,150 ) —  
Net cash provided by (used in) investing activities 473,495   ( 63,930 )
Cash flows from financing activities:
Proceeds from issuance of 0.00 % Convertible Senior Notes due 2028, net
646,372   —  
Purchases of capped calls related to 0.00 % Convertible Senior Notes due 2028
( 35,311 ) —  
Repayment of 1.00 % Convertible Senior Notes due 2027
( 1,102,659 ) —  
Payment of issuance costs for revolving credit agreement
( 2,414 ) —  
Proceeds from exercise of stock options and other types of equity, net 208,327   266,673  

(Repayment of) proceeds from development derivative, net
( 64,822 ) ( 3,511 )

Net cash used in (provided by) financing activities ( 350,507 ) 263,162  
Effect of exchange rate changes on cash, cash equivalents and restricted cash 40,637   2,032  
Net increase in cash, cash equivalents and restricted cash 524,150   287,614  
Cash, cash equivalents and restricted cash, beginning of period 968,652   814,884  
Cash, cash equivalents and restricted cash, end of period $ 1,492,802   $ 1,102,498  
Supplemental disclosure of cash flows:
Cash paid for interest $ 105,390   $ 55,248  
Cash paid for taxes $ 2,375   $ 8,168  
Operating lease right-of-use assets obtained in exchange for new operating lease liabilities
$ 12,379   $ 9,732  
Supplemental disclosure of noncash investing activities:
Capital expenditures included in accounts payable and accrued expenses $ 9,604   $ 742  

The accompanying notes are an integral part of these condensed consolidated financial statements.
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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 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 September 30, 2025, 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, 2024, which were included in our Annual Report on Form 10-K that was filed with the Securities and Exchange Commission on February 13, 2025. 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. Certain prior period amounts in the condensed consolidated financial statements have been reclassified to conform to the current period presentation.
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, 2024. There have been no material changes to our significant accounting policies during the nine months ended September 30, 2025.
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, liability related to the sale of future royalties, development derivative liability, income taxes, deferred tax asset valuation allowances, revenue recognition, research and development expenses, and stock-based compensation expense. We base our estimates on historical experience and on various other 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, and available borrowing capacity under the revolving credit agreement, or the Revolving Credit Agreement, as of September 30, 2025, 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.
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ALNYLAM PHARMACEUTICALS, INC.
NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS
(Unaudited)

Recent Accounting Pronouncements
In September 2025, the Financial Accounting Standards Board, or FASB, issued 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 . The guidance refines the scope of Topic 815 to clarify which contracts are subject to derivative accounting. The guidance also provides clarification under Topic 606 for share-based payments from a customer in a revenue contract. The standard will be effective for annual reporting periods beginning after December 15, 2026, and interim reporting periods within those annual reporting periods, with early adoption permitted. The standard updates may be applied on either a prospective or a modified retrospective basis. We are currently evaluating the impact this guidance could have on our condensed consolidated financial statements and related disclosures.
In September 2025, the 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 2024-04, Induced Conversions of Convertible Debt Instruments, which clarifies the requirements for determining whether certain settlements of convertible debt instruments should be accounted for as an induced conversion or extinguishment of convertible debt. We adopted ASU 2024-04 in the third quarter of 2025 and applied it on a retrospective basis as of January 1, 2025. The adoption did not have a material effect on our condensed consolidated financial statements, but we applied the guidance to the repurchase of our 1.00 % Convertible Senior Notes due 2027, or the 2027 Notes, in the third quarter of 2025. Please refer to Note 8, Convertible Debt and Other Financing, for further information related to the repurchase.
In November 2024, the FASB issued ASU 2024-03, Disaggregation of Income Statement Expenses , 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. The standard 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.
In December 2023, the FASB issued ASU 2023-09, Improvements to Income Tax Disclosures , which requires entities to disclose disaggregated information about their effective tax rate reconciliation as well as expanded information on income taxes paid by jurisdiction. The disclosure requirements will be applied on a prospective basis, with the option to apply them retrospectively. The standard is effective for annual reporting periods beginning after December 15, 2024, with early adoption permitted. We are currently evaluating the disclosure requirements related to ASU 2023-09.
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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) consist of the following:

Three Months Ended September 30, Nine Months Ended September 30,
(In thousands) 2025 2024 2025 2024
AMVUTTRA
United States $ 530,347   $ 168,658   $ 1,089,657   $ 447,359  
Europe 111,944   65,140   284,900   165,633  
Rest of World 43,012   24,792   112,691   70,948  
Total 685,303   258,590   1,487,248   683,940  

ONPATTRO
United States 12,480   16,207   50,105   54,858  
Europe 19,678   24,327   67,465   106,091  
Rest of World 6,917   9,759   23,532   35,805  
Total 39,075   50,293   141,102   196,754  

Total TTR
724,378   308,883   1,628,350   880,694  

GIVLAARI
United States 50,426   40,372   149,371   120,328  
Europe 18,706   16,281   58,216   47,910  
Rest of World 4,742   14,390   14,104   22,988  
Total 73,874   71,043   221,691   191,226  

OXLUMO
United States 20,727   14,933   50,855   44,009  
Europe 22,346   19,977   65,259   61,907  
Rest of World 9,757   5,310   25,677   17,561  
Total 52,830   40,220   141,791   123,477  

Total Rare
126,704   111,263   363,482   314,703  

Total net product revenues $ 851,082   $ 420,146   $ 1,991,832   $ 1,195,397  

As of September 30, 2025 and December 31, 2024, net product revenue-related receivables of $ 572.8 million and $ 269.9 million, respectively, were included in accounts receivable, net on our condensed consolidated balance sheets.
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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 Trade Discounts and Allowances Returns Reserve and Other Incentives Total
Beginning balance as of December 31, 2024
$ 350,908   $ 975   $ 9,933   $ 361,816  
Provision related to current period sales 522,200   7,748   52,456   582,404  
Provision related to prior period sales
( 43,500 ) —   —   ( 43,500 )
Credit or payments made during the period for current period sales
( 240,997 ) ( 6,003 ) ( 34,834 ) ( 281,834 )
Credit or payments made during the period for prior period sales
( 51,896 ) ( 926 ) ( 6,648 ) ( 59,470 )
Total as of September 30, 2025
$ 536,715   $ 1,794   $ 20,907   $ 559,416  

4. NET REVENUES FROM COLLABORATIONS
Net revenues from collaborations consist of the following:

Three Months Ended September 30, Nine Months Ended September 30,
(In thousands) 2025 2024 2025 2024
Roche
$ 326,604   $ 16,289   $ 361,927   $ 107,475  
Regeneron Pharmaceuticals 22,542   37,948   106,123   272,141  
Novartis AG —   2,936   —   19,756  

Other 2,596   214   44,373   3,901  
Total $ 351,742   $ 57,387   $ 512,423   $ 403,273  

The following table presents the balance of our receivables and contract liabilities related to our collaboration agreements:

(In thousands) As of September 30, 2025 As of December 31, 2024
Receivables included in accounts receivable, net
$ 346,625   $ 102,743  

Contract liabilities included in deferred revenue
$ 2,541   $ 55,481  

We recognized net revenues from collaborations of $ 12.5 million and $ 53.6 million in the three and nine months ended September 30, 2025, respectively, and $ 19.5 million and $ 248.6 million in the three and nine months ended September 30, 2024, 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.
Product Collaborations
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
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development activities that are conducted to support regulatory approval of zilebesiran solely in the Co-Commercialization 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
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the assumptions used to determine the transaction price allocated to the obligation, the revenue recognized for this obligation 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 September 30, 2025, the total transaction price was determined to be $ 1.74  billion, an increase of $ 423.6  million from December 31, 2024 attributed to the achievement of a $ 300.0  million development milestone due to us upon the first patient dosing in the ZENITH Phase 3 study in September 2025, as well as a higher probability of success associated with initiation of the Phase 3 study offset by a decrease in the expected costs to perform the development services based on an updated development plan approved by the joint steering committee in September 2025. We recognized $ 300.0  million in net revenue from collaborations as the development milestone specifically relates to the transfer of the license to Roche which occurred on the Effective Date.
The following table provides a summary of the transaction price allocated to each performance obligation:

(In thousands)
As of September 30, 2025
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 consist of the following:

Three Months Ended September 30, Nine Months Ended September 30,
(In thousands) 2025 2024 2025 2024
Roche License Obligation
$ 300,000   $ —   $ 300,000   $ 65,000  
Roche Development Services Obligation
25,166   14,884   57,696   34,832  

Other
1,438   1,405   4,231   7,643  
Total
$ 326,604   $ 16,289   $ 361,927   $ 107,475  

As of September 30, 2025, the aggregate amount of the transaction price allocated to the Roche Performance Obligations that was unsatisfied was $ 935.7 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 $ 44.8 million and $ 105.6 million, during the three and nine months ended September 30, 2025, respectively, and $ 27.8 million and $ 72.1 million, during the three and nine months ended September 30, 2024, 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
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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.
Under the terms of the Regeneron Collaboration, we continue to work exclusively with Regeneron to discover RNAi therapeutics for eye and CNS diseases for an initial research period of up to seven years , which we refer to as the Initial Research Term. Regeneron has an option to extend the Initial Research Term (referred to as the Research Term Extension Period, and together with the Initial Research Term, the Research Term) for up to an additional five years , for a research term extension fee of $ 300.0 million. The Regeneron Collaboration also covers a select number of RNAi therapeutic programs designed to target genes expressed in the liver.
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. In addition, we and Regeneron are continuing to advance programs nominated during the Initial Research Term, and Regeneron has the right to nominate up to six additional targets per year during this period. 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. If Regeneron exercises the option to extend the research term, Regeneron will retain the right to nominate up to six additional targets per year, and we will remain eligible to achieve $ 2.5  million in funding at each program initiation and an additional $ 2.5  million at each lead candidate identification during the Research Term Extension Period.
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.
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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 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 September 30, 2025, the total transaction price was determined to be $ 100.5  million related to this obligation. As of September 30, 2025, the aggregate amount of the transaction price that was unsatisfied was $ 34.3  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 consist of the following:

Three Months Ended September 30, Nine Months Ended September 30,
(In thousands) 2025 2024 2025 2024
Research Services Obligation
$ 12,540   $ 11,100   $ 39,306   $ 29,800  
C5 License Obligation
—   8,400   21,370   18,900  
C5 Monotherapy Obligation
—   —   —   191,520  
C5 Co-Co Obligation
—   —   —   700  
Regeneron Technology Transfer Obligation
—   —   2,431   —  
Other license programs
10,002   18,448   43,016   31,221  
Total
$ 22,542   $ 37,948   $ 106,123   $ 272,141  

Revenue recognized for the “Other license programs” relates to seven separate programs subject to individual license agreements with Regeneron.
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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. The composition of deferred revenue related to the Regeneron Collaboration is as follows:

(In thousands) As of September 30, 2025

Research Services Obligation
$ 2,541  
Total
$ 2,541  

(In thousands) As of December 31, 2024

Research Services Obligation
$ 41,156  
C5 License Obligation
12,018  
Regeneron Technology Transfer Obligation
2,307  
Total
$ 55,481  

We incurred research and development costs related to the Regeneron Collaboration of $ 14.6 million and $ 46.1 million, during the three and nine months ended September 30, 2025, respectively, and $ 27.9 million and $ 60.8 million, during the three and nine months ended September 30, 2024, respectively.
Novartis AG
In February 2013, we entered into a license and collaboration agreement with The Medicines Company, or MDCO, pursuant to which we granted to MDCO an exclusive, worldwide license to develop, manufacture and commercialize RNAi therapeutics targeting proprotein convertase subtilisin/kexin type 9 for the treatment of hypercholesterolemia and other human diseases, including inclisiran. We refer to this agreement, as amended through the date hereof, as the MDCO License Agreement. In 2020, Novartis AG, or Novartis, completed its acquisition of MDCO and assumed all of MDCO’s rights and obligations under the MDCO License Agreement. We are entitled to royalties ranging from 10 % up to 20 % based on annual worldwide net sales of licensed products by Novartis, its affiliates and sublicensees, subject to reduction under specified circumstances.
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 nine months ended September 30, 2025.
Other
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.
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5. FAIR VALUE MEASUREMENTS
The following tables present information about our financial assets and liabilities 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 September 30, 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 $ 121,966   $ 121,966   $ —   $ —  
U.S. treasury securities 14,952   —   14,952   —  
Commercial paper 10,072   —   10,072   —  

Marketable debt securities:
U.S. treasury securities 638,615   —   638,615   —  
Corporate notes 343,349   —   343,349   —  
U.S. government-sponsored enterprise securities 238,743   —   238,743   —  
Commercial paper 8,654   —   8,654   —  

Municipal securities 5,014   —   5,014   —  

Restricted cash (money market funds) 916   916   —   —  
Total financial assets $ 1,382,281   $ 122,882   $ 1,259,399   $ —  
Financial liabilities
Development derivative liability $ 560,910   $ —   $ —   $ 560,910  

(In thousands) As of December 31, 2024 Quoted Prices in Active Markets
(Level 1) Significant Observable Inputs
(Level 2) Significant Unobservable Inputs
(Level 3)
Financial assets
Cash equivalents:
Money market funds $ 190,779   $ 190,779   $ —   $ —  
U.S. treasury securities 36,428   —   36,428   —  
Commercial paper 22,709   —   22,709   —  
U.S. government-sponsored enterprise securities 9,952   —   9,952   —  

Marketable debt securities:
U.S. treasury securities 921,627   —   921,627   —  
U.S. government-sponsored enterprise securities 396,143   —   396,143   —  
Corporate notes 361,739   —   361,739   —  
Commercial paper 35,408   —   35,408   —  

Municipal securities 5,003   —   5,003   —  
Marketable equity securities 8,156   8,156   —   —  
Restricted cash (money market funds) 910   910   —   —  
Total financial assets $ 1,988,854   $ 199,845   $ 1,789,009   $ —  
Financial liabilities
Development derivative liability $ 486,919   $ —   $ —   $ 486,919  

During the three and nine months ended September 30, 2025 and 2024, 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.
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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 nine months ended September 30, 2025 or 2024.
The following tables summarize our marketable debt securities:

As of September 30, 2025
(In thousands) Amortized
Cost Gross Unrealized Gains
Gross Unrealized Losses
Fair Value
U.S. treasury securities $ 651,985   $ 1,621   $ ( 39 ) $ 653,567  
Corporate notes 342,147   1,207   ( 5 ) 343,349  
U.S. government-sponsored enterprise securities 238,179   614   ( 50 ) 238,743  
Commercial paper 18,726   —   —   18,726  
Municipal securities 5,000   14   —   5,014  
Total $ 1,256,037   $ 3,456   $ ( 94 ) $ 1,259,399  

As of December 31, 2024
(In thousands) Amortized
Cost Gross Unrealized Gains
Gross Unrealized Losses
Fair Value
U.S. treasury securities $ 957,145   $ 1,377   $ ( 467 ) $ 958,055  
U.S. government-sponsored enterprise securities 405,890   575   ( 370 ) 406,095  
Corporate notes 361,311   769   ( 341 ) 361,739  
Commercial paper 58,117   —   —   58,117  

Municipal securities 5,002   1   —   5,003  
Total $ 1,787,465   $ 2,722   $ ( 1,178 ) $ 1,789,009  

The fair values of our marketable debt securities by classification in the condensed consolidated balance sheets were as follows:

(In thousands) As of September 30, 2025 As of December 31, 2024
Marketable debt securities $ 1,234,375   $ 1,719,920  
Cash and cash equivalents 25,024   69,089  
Total $ 1,259,399   $ 1,789,009  

7. OTHER BALANCE SHEET DETAILS
Inventory
The components of inventory are summarized as follows:

(In thousands) As of September 30, 2025 As of December 31, 2024
Raw materials $ 22,251   $ 23,965  
Work in process
35,504   64,978  
Finished goods 38,850   26,433  
Total inventory
$ 96,605   $ 115,376  

As of September 30, 2025 and December 31, 2024, we had $ 21.2 million and $ 36.9 million of long-term inventory, respectively, included within other assets in our condensed consolidated balance sheets as we anticipate it being consumed beyond our normal operating cycle.
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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 September 30,
(In thousands) 2025 2024
Cash and cash equivalents $ 1,490,249   $ 1,099,920  
Total restricted cash included in other assets 2,553   2,578  
Total cash, cash equivalents, and restricted cash shown in the condensed consolidated statements of cash flows
$ 1,492,802   $ 1,102,498  

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, 2024 $ ( 32,792 ) $ ( 4,249 ) $ 1,544   $ 979   $ ( 34,518 )
Other comprehensive income before reclassifications
—   —   3,001   10,764   13,765  
Amounts reclassified from accumulated other comprehensive loss
—   161   ( 1,183 ) —   ( 1,022 )
Net other comprehensive income
—   161   1,818   10,764   12,743  
Balance as of September 30, 2025 $ ( 32,792 ) $ ( 4,088 ) $ 3,362   $ 11,743   $ ( 21,775 )

(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, 2023 $ ( 32,792 ) $ ( 2,753 ) $ 1,548   $ 10,622   $ ( 23,375 )
Other comprehensive loss before reclassifications
—   —   ( 4 ) ( 6,327 ) ( 6,331 )
Amounts reclassified from accumulated other comprehensive loss
—   93   4,787   —   4,880  
Net other comprehensive income (loss)
—   93   4,783   ( 6,327 ) ( 1,451 )
Balance as of September 30, 2024 $ ( 32,792 ) $ ( 2,660 ) $ 6,331   $ 4,295   $ ( 24,826 )

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 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.
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NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS
(Unaudited)

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 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, 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 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 this quarter.
The 2028 Notes were issued at par. As of September 30, 2025, the 2028 Notes were classified as a long-term liability on the condensed consolidated balance sheet and had a carrying value of $ 646.0 million, representing the outstanding principal amount, net of unamortized issuance costs of $ 15.3 million. The issuance costs are amortized to interest expense over the contractual term of the 2028 Notes. As of September 30, 2025, the estimated fair value of the 2028 Notes was approximately $ 655.3 million, which was determined based on the last actively traded price per $100 of the 2028 Notes (Level 2) on that day. As of September 30, 2025, the effective interest rate of the 2028 Notes is 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 cap price of the 2025 Capped Call Transactions is initially $ 837.61 per share, which represents a premium of 75 % 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, 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
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NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS
(Unaudited)

stockholders’ equity and are not accounted for as derivatives. The $ 35.3 million cost incurred in connection with the 2025 Capped Call Transactions 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 issued and outstanding 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.
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 met in the third quarter of 2025 due to our common stock trading for at least 20 days during a period of 30 consecutive trading days ending on, and including, the last trading day of the quarter above 130 % of the conversion price, and the 2027 Notes became convertible in the fourth quarter of 2025.
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 September 30, 2025, we have not redeemed any of the 2027 Notes under this option.
No sinking fund is provided for the Notes and therefore we are not required to redeem or retire the 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 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 in accordance with ASU 2024-04. We recorded an inducement expense of $ 39.1 million within loss related to convertible debt in the condensed consolidated statements of operations and comprehensive income (loss) for the three and nine months ended September 30, 2025 and a charge to additional paid-in capital of $ 430.4  million within stockholders’ equity. As of September 30, 2025, we had $ 397.2 million of aggregate principal amount of the 2027 Notes outstanding.
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NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS
(Unaudited)

As of September 30, 2025 and December 31, 2024, the 2027 Notes were classified as a long-term liability on the consolidated balance sheets and had a carrying value of $ 394.3 million and $ 1.02 billion, respectively, representing outstanding principal amount net of unamortized issuance costs of $ 2.9 million and $ 10.4 million, respectively. The issuance costs are amortized to interest expense over the contractual term of the 2027 Notes. As of September 30, 2025 and December 31, 2024, the estimated fair value of the 2027 Notes was approximately $ 652.9 million and $ 1.11 billion, 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 September 30, 2025 and December 31, 2024, the effective interest rate of the 2027 Notes is 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 September 30, 2025, 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.
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 September 30, 2025, we had no borrowings and $ 17.5  million of letters of credit outstanding under the Revolving Credit Agreement.

9. LIABILITY RELATED TO THE SALE OF FUTURE ROYALTIES
As of September 30, 2025 and December 31, 2024, the carrying value of the liability related to the sale of future royalties was $ 1.46  billion, net of closing costs of $ 8.5  million, and $ 1.45  billion, net of closing costs of $ 9.1  million, respectively. The carrying value of the liability related to the sale of future royalties approximates fair value as of September 30, 2025 and is based on our current estimates of future royalties expected to be paid over the life of the arrangement, which are considered Level 3 inputs.
The following table shows the activity with respect to the liability related to the sale of future royalties, in thousands:

Carrying value as of December 31, 2024
$ 1,447,371  
Interest expense
112,298  
Payments ( 94,812 )
Carrying value as of September 30, 2025
$ 1,464,857  

10. DEVELOPMENT DERIVATIVE LIABILITY
As of September 30, 2025 and December 31, 2024, we recorded $ 121.3  million and $ 93.8  million, respectively, within development derivative liability and $ 439.7  million and $ 393.1  million, respectively, within development derivative liability, net of current portion on our condensed consolidated balance sheets, based on expected timing of our payments to BXLS V
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NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS
(Unaudited)

Bodyguard – PCP L.P. and BXLS Family Investment Partnership V – ESC L.P., collectively referred to as Blackstone Life Sciences. The change in fair value due to the remeasurement of the development derivative liability is recorded within other expense, net on our condensed consolidated statements of operations and comprehensive income (loss).
As of September 30, 2025, the derivative liability is classified as a Level 3 financial liability in the fair value hierarchy. The valuation method incorporates certain unobservable Level 3 key inputs, including (i) the probability and timing of achieving stated development milestones to receive payments from Blackstone Life Sciences, (ii) the probability and timing of achieving regulatory approval and payments to Blackstone Life Sciences, (iii) an estimate of the amount and timing of the royalty payable on net sales of AMVUTTRA, (iv) our cost of borrowing ( 10 %), and (v) Blackstone Life Sciences’ cost of borrowing ( 7 %).
The following table presents the activity with respect to the development derivative liability, in thousands:

Carrying value as of December 31, 2024
$ 486,919  

Change in fair value
138,813  
Payments
( 64,822 )
Carrying value as of September 30, 2025
$ 560,910  

11. 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 (deficit):

  Three Months Ended September 30, Nine Months Ended September 30,
(In thousands) 2025 2024 2025 2024
Research and development $ 48,725   $ 19,794   $ 122,075   $ 87,124  
Selling, general and administrative 59,486   26,010   154,528   93,315  
Total stock-based compensation expense
108,211   45,804   276,603   180,439  
Capitalized stock-based compensation costs
1,128   808   3,383   2,424  
Total stock-based compensation charges
$ 109,339   $ 46,612   $ 279,986   $ 182,863  

12. 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.
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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 September 30, Nine Months Ended September 30,
(In thousands, except per share amounts)
2025 2024 2025 2024
Net income (loss), as reported $ 251,084   $ ( 111,570 ) $ 127,328   $ ( 194,394 )
Adjustment for the elimination of interest expense on the convertible debt
1,608   —   —   —  
Net income (loss), for use in diluted income per share $ 252,692   $ ( 111,570 ) $ 127,328   $ ( 194,394 )

Weighted-average common shares — basic
131,447   128,590   130,590   127,159  
Effect of dilutive securities:

Convertible debt 1,583   —   —   —  
Options to purchase common stock, inclusive of performance-based stock options 2,454   —   2,245   —  
Restricted stock units, inclusive of performance-based restricted stock units
1,847   —   1,304   —  
Employee stock purchase program
17   —   7   —  
Weighted-average common shares — diluted
137,348   128,590   134,146   127,159  

Net income (loss) per common share — basic $ 1.91   $ ( 0.87 ) $ 0.98   $ ( 1.53 )
Net income (loss) per common share — diluted $ 1.84   $ ( 0.87 ) $ 0.95   $ ( 1.53 )

The following table sets forth the potential common shares (prior to consideration of the treasury stock or if-converted methods) excluded from the calculation of diluted net loss per common share because their inclusion would be anti-dilutive:

Three Months Ended September 30, Nine Months Ended
September 30,
(In thousands) 2025 2024 2025 2024
Options to purchase common stock, inclusive of performance-based stock options —   5,388   157   5,388  
Unvested restricted stock units, inclusive of performance-based restricted stock units 3   2,779   7   2,779  
Convertible debt 1,788   3,616   3,491   3,616  
Total 1,791   11,783   3,655   11,783  

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 nine months ended September 30, 2025, we excluded 5.8 million shares and 5.4 million shares, respectively, and in the three and nine months ended September 30, 2024, we excluded 5.2 million shares related to these transactions.

13. 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 September 30, 2025, 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 course of our business, including the matters described below. The claims and legal proceedings in which we could be involved include challenges to the scope, validity or enforceability of patents relating to our products or product candidates, and challenges by us to the scope,
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NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS
(Unaudited)

validity or enforceability of the patents held by others. These include claims by third parties that we infringe their patents or breach our license or other agreements with such third parties. 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, our business, results of operations, liquidity and financial condition could be adversely affected. Our accounting policy for accrual of legal costs is to recognize such expenses as incurred.
Patent Infringement Lawsuits
In March 2022, we filed separate lawsuits in the U.S. District Court for the District of Delaware, or the District Court, against (1) Moderna, Inc. and its subsidiaries ModernaTX, Inc. and Moderna US, Inc., collectively referred to as Moderna, which we refer to as the Moderna lawsuit, and (2) Pfizer Inc. and its subsidiary Pharmacia & Upjohn Co. LLC, collectively referred to as Pfizer, which we refer to as the Pfizer lawsuit, seeking damages for patent infringement in Moderna’s and Pfizer’s manufacture and sale of their messenger RNA, or mRNA, COVID-19 vaccines. In May 2022, Pfizer added BioNTech SE to the Pfizer lawsuit. In August 2025, we and Moderna settled all claims between the parties in the Moderna lawsuit, and in September 2025, we and Pfizer settled all claims between the parties in the Pfizer lawsuit.
On July 12, 2024, Acuitas Therapeutics, Inc., or Acuitas, filed a declaratory judgment action against us in the District Court, seeking a judgment adding certain Acuitas employees as co-inventors on the patents we have asserted against Pfizer/BioNTech and Moderna in our lawsuits. On September 19, 2024, we filed a motion to dismiss, arguing Acuitas did not have standing to sue and failed to state a claim upon which relief could be granted. On July 1, 2025, the District Court granted our motion to dismiss the complaint without prejudice, finding that the plaintiffs had failed to plead facts sufficient to establish standing.
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, which remains pending before the Texas District Court. In light of the early stage of this matter, a loss is not probable or reasonably estimable at this time.
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
intend to produce records responsive to the subpoena.
Indemnifications
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 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 September 30, 2025.

14. 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
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NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS
(Unaudited)

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
September 30, Nine Months Ended
September 30,
(In thousands)
2025 2024 2025 2024
Clinical research and outside services $ 170,756   $ 134,880   $ 438,791   $ 379,886  
Compensation and related 146,089   95,110   388,726   326,411  
Occupancy and all other costs (1)
41,969   40,936   120,040   119,766  
Total research and development expense
$ 358,814   $ 270,926   $ 947,557   $ 826,063  

Selling, General and Administrative

Three Months Ended
September 30, Nine Months Ended
September 30,
(In thousands)
2025 2024 2025 2024
Compensation and related
$ 188,669   $ 115,683   $ 511,339   $ 370,735  
Consulting and professional services
88,738   68,329   236,062   191,819  
Occupancy and all other costs (1)
44,669   36,981   137,938   117,633  
Total selling, general and administrative expense
$ 322,076   $ 220,993   $ 885,339   $ 680,187  

(1) Occupancy and all other costs includes facilities, information technology, depreciation and certain departmental expenses .

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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 developed 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 a 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. 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 2021, we launched our Alnylam P 5 x25 strategy, which focuses on our planned transition to a top-tier biotech company by the end of 2025. With Alnylam P 5 x25 , we aim to deliver transformative medicines across a broad range of disease areas and indications, benefiting patients around the world through sustainable innovation and exceptional financial performance, resulting in a leading biotech profile.
We currently have six marketed products and more than 20 clinical programs, including several in late-stage development.
AMVUTTRA is approved in the 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. Regulatory reviews continue in other territories. 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 each of 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 the Colombian Health Authority for the treatment of ATTR amyloidosis with cardiomyopathy.
ONPATTRO is approved in the United States, or U.S., for the treatment of the polyneuropathy of hATTR amyloidosis in adults and has also been 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 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 2025 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 2025 and beyond.
Leqvio (inclisiran), our fifth product, 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 maximally tolerated statin therapy for the treatment of adults with
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heterozygous familial hypercholesterolemia, or HeFH, or clinical atherosclerotic cardiovascular disease, or ASCVD, who require additional lowering of low-density lipoprotein cholesterol, or LDL-C. In July 2023, the FDA approved an expanded indication for Leqvio to include treatment of adults with high LDL-C and who are at increased risk of heart disease. Leqvio has also been approved in China and Japan, and as of the end of September 2025, Leqvio had been registered in more than 107 countries worldwide and was commercially available in 87 countries.
Qfitlia (fitusiran), our sixth product, 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). 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. Regulatory submissions for Qfitlia have also been completed in China and Brazil.
In addition to our marketed products, as part of our Alnylam P 5 x25 strategy, we have multiple drivers of future growth, including the development of transformative medicines to treat prevalent disease. In addition to Leqvio, we are advancing zilebesiran, an investigational, subcutaneously administered RNAi therapeutic targeting angiotensinogen in development 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 March 2024, we reported positive topline results from our KARDIA-2 clinical trial, which is designed to evaluate the safety and efficacy of zilebesiran administered biannually as a concomitant therapy in patients whose blood pressure is not adequately controlled by a standard of care antihypertensive medication. 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 ( Z ileb E sira N Card I ovascular Ou T come Study in H ypertension), 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 nucresiran (formerly ALN-TTRsc04), an 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 a single dose of nucresiran at 300 mg or higher resulted in mean reductions of serum TTR of greater than 90% from baseline achieved at Day 15 and were sustained through at least Day 180. We have initiated the TRITON-CM Phase 3 clinical trial of nucresiran in patients with ATTR amyloidosis with cardiomyopathy and in October 2025, we announced that initiation is underway in the TRITON-PN Phase 3 clinical trial of nucresiran in patients with hATTR polyneuropathy.
We are also advancing mivelsiran (formerly ALN-APP), an investigational RNAi therapeutic targeting amyloid precursor protein in development for the treatment of Alzheimer’s disease, or AD, and cerebral amyloid angiopathy, or CAA. In July 2025, we presented multiple and single 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 (sAPPβ) in cerebrospinal fluid. Further lowering of sAPPβ was observed after administration of a second 50 mg dose of mivelsiran. In July 2024, we initiated dosing in the cAPPricorn-1 Phase 2 clinical trial of mivelsiran in patients with CAA. We expect to initiate a Phase 2 clinical trial of mivelsiran in patients with AD in the fourth quarter of 2025.
We have additional late-stage investigational programs advancing toward potential commercialization, including cemdisiran for the treatment of complement-mediated diseases, which our collaborator, Regeneron Pharmaceuticals, Inc., or Regeneron, is advancing in combination with pozelimab in Phase 3 clinical trials in myasthenia gravis, geographic atrophy and paroxysmal nocturnal hemoglobinuria. In August 2025, Regeneron announced that cemdisiran monotherapy met the primary and key secondary endpoints from the Phase 3 NIMBLE clinical trial of cemdisiran in generalized myasthenia gravis, and also announced that a U.S. regulatory submission for cemdisiran monotherapy is planned for the first quarter of 2026, pending discussions with the FDA.
In further support of our Alnylam P 5 x25 strategy and in view of our evolving risk profile, we remain focused on the continued evolution of our global infrastructure, including key objectives such as optimizing our global structure for execution in key markets, enhancing performance consistent with our values, and continuing to strengthen our culture. We continue to build our global compliance program to drive its evolution and enhancement through the launch of new systems and leveraging data analytics to strengthen the efficiency and effectiveness of our program. Building from our global Code of Business Conduct and Ethics, our compliance program is designed to empower our employees and those with whom we work to execute on our strategy consistent with our values and in compliance with applicable laws and regulations, and to mitigate risk. Comprised of components such as risk assessment and monitoring; policies, procedures, and guidance; training and communications; dedicated resources; and systems and processes supporting activities such as third party engagements and
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investigations and remediation, and our enterprise risk management program; our program and related controls are built to enhance our business processes, structures, and controls across our global operations, and to empower ethical decision making.
Based on our expertise in RNAi therapeutics and broad intellectual property estate, we have formed collaborations with leading pharmaceutical and life sciences companies to support our development and commercialization efforts, including Roche, Regeneron, Sanofi, and Novartis (which acquired our collaborator The Medicines Company, or MDCO, in 2020).
We have incurred significant losses since we commenced operations in 2002 and as of September 30, 2025, we had an accumulated deficit of $7.16 billion. Historically, we have generated losses principally from costs associated with research and development activities, acquiring, filing and expanding intellectual property rights, and selling, general and administrative costs. As a result of planned expenditures for research and development activities relating to our research platform, our drug development programs, including clinical trial and manufacturing costs, the continued build-out of late-stage clinical and commercial capabilities, including global commercial operations, continued management and growth of our patent portfolio, collaborations and general corporate activities, we may incur additional operating losses. While we are targeting financial self-sustainability by the end of 2025, we will continue to require significant resources over the next several years as we expand our efforts to discover, develop and commercialize RNAi therapeutics. 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.
We currently have programs focused on a number of therapeutic areas and, as of September 30, 2025, we generate worldwide product revenues from four commercialized products, AMVUTTRA, ONPATTRO, GIVLAARI and OXLUMO, primarily in the U.S. and Europe. However, our ongoing development and regulatory efforts may not be successful and we may not be able to commence sales of any other products and/or successfully market and sell our existing commercialized products or any other approved products in the future. A meaningful portion of our total revenues in recent years has been derived from collaboration revenues from collaborations with Roche, Regeneron and Novartis. In addition to revenues from the commercial sales of our approved products and potentially from sales of future products, we expect our sources of potential funding for the next several years to continue to be derived in part from existing and new strategic collaborations. Such collaborations include, or may include in the future, license and other fees, equity investments, funded research and development, milestone payments and royalties on product sales by our collaborators.
Convertible Senior Notes and Repurchases
In September 2025, we issued $661.25 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 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 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 all 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 cap price of the capped call transaction will initially be approximately $837.61 per share, which represents a premium of approximately 75.0% 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 $478.6327 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 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 $1,105.8 million.
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.
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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
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, European Medicines Agency, or EMA, or any other health authority and no conclusions can or should be drawn regarding the safety or efficacy of these investigational therapeutics.
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The table below represents our commercial products and late- and early-stage development programs as of October 30, 2025.

During the third quarter of 2025 and recent period, we reported the following updates from our commercially approved products and our late-stage clinical programs:
Commercial
Total TTR: AMVUTTRA & ONPATTRO
• We achieved global net product revenues for AMVUTTRA and ONPATTRO for the third quarter of 2025 of $685.3 million and $39.1 million, respectively.
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Total Rare: GIVLAARI & OXLUMO
• We achieved global net product revenues for GIVLAARI and OXLUMO for the third quarter of 2025 of $73.9 million and $52.8 million, respectively.
Late-Stage Clinical Development
• Announced that initiation is underway in the TRITON-PN Phase 3 trial of nucresiran in patients with hATTR-PN.
• Reported results from the Phase 2 KARDIA-3 trial and initiated the ZENITH Phase 3 cardiovascular outcomes trial of zilebesiran, an investigational RNAi therapeutic, in patients with hypertension.
• Initiated a Phase 2 trial of ALN-6400, an investigational RNAi therapeutic targeting plasminogen for bleeding disorders, in patients with hereditary hemorrhagic telangiectasia (HHT).
• Our partner, Regeneron, announced positive results from the Phase 3 NIMBLE trial of cemdisiran, an investigational RNAi therapeutic, in generalized myasthenia gravis.
◦ Cemdisiran monotherapy, dosed subcutaneously every three months, met the primary and key secondary endpoints, showing a 2.3-point placebo-adjusted improvement in the Myasthenia Gravis Activities of Daily Living total score.
◦ Regeneron is planning a U.S. regulatory submission for cemdisiran monotherapy in the first quarter of 2026, pending discussions with the FDA.
There is a risk that any drug discovery or development program may not produce revenue for a variety of reasons, including the possibility that we will not be able to adequately demonstrate the safety and effectiveness of the product candidate or obtain approval or the desired labeling for the product candidate from regulatory authorities. The success of AMVUTTRA, ONPATTRO, GIVLAARI, OXLUMO or any other product candidate we develop is highly uncertain. Due to the numerous risks associated with developing drugs, we cannot reasonably estimate or know the nature, timing and estimated costs of the efforts necessary to complete the development of any potential product candidate or indication, or the period, if any, in which material net cash inflows will commence from any approved product or indication. Any failure to complete any stage of the development of any potential products in a timely manner or successfully launch, market and sell any of our commercially approved products, could have a material adverse effect on our operations, financial position and liquidity. A discussion of some of the risks and uncertainties associated with completing our research and development programs within the planned timeline, or at all, and the potential consequences of failing to do so, are set forth in Part II, Item 1A below under the heading “Risk Factors.”
Strategic Collaborations
Our business strategy is to develop and commercialize a broad pipeline of RNAi therapeutic products directed across a broad range of disease areas and indications. As part of this strategy, we have entered into, and expect to enter into additional, collaboration and licensing agreements as a means of obtaining resources, capabilities and funding to advance our investigational RNAi therapeutic programs. Our collaboration strategy is to form collaborations that create significant value for ourselves and our collaborators in the advancement of RNAi therapeutics. We expect these collaborations to provide us with financial support in the form of upfront cash payments, license fees, equity investments, research and development and sales and marketing support and/or funding, milestone payments and/or royalties or profit sharing based on sales of RNAi therapeutics.
Below is a brief description of certain of our key collaborations.
Roche . In July 2023, we entered into the Roche Collaboration and License Agreement, pursuant to which we and Roche established a worldwide, strategic collaboration for the joint development of pharmaceutical products containing zilebesiran. Under the Roche Collaboration and License Agreement, we granted to Roche (i) co-exclusive rights to develop zilebesiran worldwide and commercialize zilebesiran in the U.S., (ii) exclusive rights to commercialize zilebesiran outside of the U.S., and (iii) non-exclusive rights to manufacture zilebesiran for the development and commercialization of zilebesiran outside of the U.S. Roche made an upfront payment of $310.0 million and in April 2024 we achieved the development milestone associated with the dosing of the first patient in the KARDIA-3 Phase 2 clinical trial and received a $65.0 million development milestone payment from Roche. In September 2025, we achieved the development milestone associated with the dosing of the first patient in our ZENITH Phase 3 cardiovascular outcomes trial and received a $300.0 million development milestone payment from Roche. In addition, we are eligible to receive up to an additional $2.15 billion in contingent payments based on the achievement of specified development, regulatory and sales-based milestones. We are responsible for forty percent (40%), and Roche is responsible for 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 in the U.S., and Roche is solely responsible for all costs incurred in the conduct of development activities that primarily support regulatory approval outside the U.S. Roche will be solely responsible for costs incurred in connection with commercialization of zilebesiran outside of the U.S.
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