REGENERON PHARMACEUTICALS, INC. (REGN) Risk Factors

Recent key developments

Concrete developments — dated events, named agreements and instruments, legal proceedings — that REGENERON PHARMACEUTICALS, INC. surfaced in its latest filing.

• EYLEA U.S. net product sales declined by 45% for the three months and 41% for the six months ended June 30, 2026 compared to 2025.June 30, 2026
• EYLEA HD and EYLEA U.S. net product sales represented 25% of total revenues for the six months ended June 30, 2026, with EYLEA HD U.S. net product sales representing 55% of aggregate EYLEA HD and EYLEA U.S. net product sales.June 30, 2026
• Sanofi collaboration revenue, mostly from Dupixent profits, represented 48% of total revenues for the six months ended June 30, 2026.June 30, 2026
• Amgen's Pavblu™ (aflibercept-ayyh), an EYLEA biosimilar, launched in the United States following expiration of U.S. regulatory exclusivity in May 2024, with additional biosimilar versions expected.May 2024
• Regeneron entered into U.S. Government Agreements in April 2026, agreeing to provide certain wholly-owned products to Medicaid, price certain future U.S. medicines at no greater than Most-Favored-Nation Pricing, and receive exemptions from Section 232 tariffs through January 2029 contingent on continued U.S. manufacturing and R&D investment.April 2026
• The BIOSECURE Act enacted in late 2025 could restrict engaging China-based suppliers.late 2025
• A Phase 3 trial of fianlimab in combination with Libtayo in first-line metastatic melanoma did not reach statistical significance for its primary endpoint compared to pembrolizumab monotherapy in May 2026.May 2026
• The FDA issued a Complete Response Letter (CRL) for the EYLEA HD pre-filled syringe in October 2025 due to findings from inspections at third-party manufacturers, delaying potential FDA approval.October 2025
• In March 2026, the Patent Trial and Appeal Board of the USPTO instituted a post-grant review of U.S. Patent No. 12,168,036 relating to EYLEA HD.March 2026
• Certain European patents pertaining to EYLEA HD, EYLEA, and Dupixent are subject to opposition proceedings before the EPO and/or patent offices of various European countries.
• Regeneron is party to patent infringement and other proceedings relating to EYLEA, as described in Note 12 to Condensed Consolidated Financial Statements.
• In 2018, Regeneron entered into a license agreement with Bristol-Myers Squibb, E. R. Squibb & Sons, and Ono Pharmaceutical to obtain a license under certain patents to develop and sell Libtayo.2018
• In October 2023, the FDA issued a CRL for the sBLA for Dupixent in chronic spontaneous urticaria (CSU) requiring additional efficacy data, delaying approval by nearly 18 months.October 2023
• In July 2025, the FDA issued a CRL concerning the BLA for odronextamab in relapsed/refractory follicular lymphoma due to findings from inspections at third-party manufacturers.July 2025
• Bulk manufacturing production at the Limerick, Ireland facility was temporarily interrupted during the first and second quarters of 2026 due to unanticipated facility repairs.first and second quarters of 2026
• In May 2022, Regeneron completed its acquisition of Checkmate Pharmaceuticals, Inc.May 2022
• In September 2023, Regeneron completed its acquisition of Decibel Therapeutics, Inc.September 2023
• In April 2024, Regeneron acquired full development and commercialization rights to 2seventy bio, Inc.'s oncology and autoimmune preclinical and clinical stage cell therapy pipeline.April 2024
• Regeneron has commenced the Antibody Collaboration Litigation against Sanofi and certain of its affiliated entities, alleging breach of provisions concerning access to commercialization information and audit rights.
• Bayer has the right to terminate its collaboration agreement with Regeneron at any time upon six or twelve months' advance notice.
• In July 2025, the U.S. and EU announced a framework trade agreement generally imposing a 15% tariff on imports from the EU, with pharmaceutical products not subject to future Section 232 duties above 15%.July 2025
• On February 20, 2026, the U.S. Supreme Court ruled that IEEPA does not confer tariff authority, leading to cessation of those duties, and on February 24, 2026, a temporary 10% surcharge under Section 122 of the Trade Act of 1974 was imposed, which expired July 24, 2026.February 20, 2026
• In April 2026, U.S. imposed new Section 232 tariffs on patented pharmaceutical imports, effective July 31, 2026 or September 29, 2026, with tiered rates based on country of origin, onshoring and pricing agreements, and product nature.April 2026
• On July 23, 2026, USTR issued a notice imposing 10% or 12.5% tariffs effective July 24, 2026 on imports from 60 countries including Canada, EU, India, Japan, and UK, with exemptions for 700 specific pharmaceutical articles, but some of Regeneron's imports may not qualify.July 23, 2026
• The 'One Big Beautiful Bill Act' signed into law in 2025 could materially adversely impact Regeneron's effective tax rate or cash flows.2025
• As of June 30, 2026, Regeneron had $2.707 billion of outstanding indebtedness under its senior unsecured notes and the lease financing facility.June 30, 2026
• As of June 30, 2026, Regeneron's five largest shareholders plus Dr. Schleifer beneficially owned approximately 31.3% of outstanding shares of Common Stock.June 30, 2026
• In July 2026, a putative class action civil complaint was filed against the Company and certain employees asserting violations of federal securities laws.July 2026
• A standstill provision in the January 2014 amended and restated investor agreement with Sanofi prohibits Sanofi from seeking control or acquiring more than 30% of Class A and Common Stock.January 2014
• Pending government proceedings and investigations, including civil proceedings initiated by the U.S. Department of Justice and the U.S. Attorney's Office for the District of Massachusetts.