This press release was originally published by Regeneron.
October 26, 2026 at 7:00 AM EDT
Updated agreement expands 2020 procurement agreement with BARDA for Regeneron’s first-in-class antibody treatment for Orthoebolavirus zairense, adding value of approximately $270 million
TARRYTOWN, N.Y., Oct. 26, 2026 (GLOBE NEWSWIRE) — Regeneron Pharmaceuticals, Inc. (NASDAQ: REGN) announced today that it has extended its agreement with the Biomedical Advanced Research and Development Authority (BARDA), part of the Administration for Strategic Preparedness and Response (ASPR) within the U.S. Department of Health and Human Services (HHS), to provide additional supply of Inmazeb® (a three-antibody cocktail of atoltivimab, maftivimab, and odesivimab-ebgn) for U.S. preparedness against Ebola disease. Inmazeb was the first Ebola treatment approved by the U.S. Food and Drug Administration (FDA), indicated specifically for infection caused by Orthoebolavirus zairense in adult and pediatric patients, including neonates born to infected mothers, and has been administered to hundreds of patients since 2019. In a clinical trial, Inmazeb reduced mortality by approximately 55 percent compared to an active control treatment in patients with low viral load. This agreement continues a partnership that began with BARDA’s original procurement of the treatment in 2020.
Under the new agreement, Regeneron expects to deliver additional treatment doses of Inmazeb treatment to the U.S. government through 2031 and receive payment of approximately $270 million.
“Maintaining a ready supply of Inmazeb is exactly the kind of preparedness this country needs for the threats we can already see on the horizon,” said Leonard S. Schleifer, M.D., Ph.D., Board Co-Chair, President and Chief Executive Officer of Regeneron. “This extended agreement reflects the strength of our long-standing collaboration with BARDA and our shared commitment to ensuring that at-the-ready medicines are available whenever an Ebola outbreak occurs.”
Maftivimab Development Program
Separately, Regeneron’s investigational maftivimab monotherapy is being added to the PARTNERS trial to assess use as a potential treatment in the current Bundibugyo virus disease outbreak
Maftivimab has demonstrated positive in vitro and non-human primate activity against Bundibugyo; preprint data now available
Separate from the Inmazeb procurement agreement, Regeneron is evaluating maftivimab, the most potent virus-neutralizing component of Inmazeb, as a potential treatment for Ebola disease caused by Bundibugyo virus, the orthoebolavirus driving the current outbreak in the Democratic Republic of the Congo (DRC) and for which there are no currently approved treatment options. Maftivimab has demonstrated strong efficacy against Bundibugyo virus in in vitro and non-human primate (NHP) studies conducted with Texas Biomedical Research Institute, supporting its continued development as a monotherapy or combination treatment candidate. These data are now available in preprint on BioRxiv.org and pending peer review publication.
“Inmazeb was created by Regeneron scientists in record time using our proprietary VelociSuite® rapid-response technologies,” said George D. Yancopoulos, M.D., Ph.D., Board Co-Chair, President and Chief Scientific Officer of Regeneron. “We are now advancing maftivimab, which has already demonstrated positive results in non-human primates infected with Bundibugyo, so that we can bring another potential Ebola treatment forward as quickly as possible to help in the current outbreak. Regeneron’s continued supply of Inmazeb to the U.S. government, our advancement of maftivimab and our partnerships to support frontline response capacity reflect the Company’s long-term commitment to infectious diseases preparedness, from the laboratory to the communities most affected by outbreaks.”
Based on in vitro and NHP efficacy studies, maftivimab is being added to the PARTNERS (Platform Adaptive Randomised Trial for New and Repurposed Filovirus TreatmentS) clinical trial, which is evaluating potential treatments for Bundibugyo virus disease. PARTNERS is delivered through a global partnership of Ministries of Health, researchers, healthcare workers and international research and non-governmental organizations. The trial has been designed and is coordinated internationally by the Pandemic Sciences Institute, University of Oxford, and is being led nationally in the DRC by the Institut National de Recherche Biomédicale (INRB), supported by the Institute of Tropical Medicine (ITM), Antwerp. The trial is sponsored by the World Health Organization (WHO) and is made possible with the support of Africa CDC.
Regeneron also continues to support Afya Foundation’s emergency response efforts aimed at safeguarding frontline healthcare workers and strengthening healthcare system resilience during the current outbreak.
About Inmazeb
Inmazeb is approved by the U.S. FDA for the treatment of infection caused by Orthoebolavirus zairense (formerly known as Zaire ebolavirus) in adult and pediatric patients, including neonates born to a mother who is RT-PCR positive for Orthoebolavirus zairense infection. Inmazeb was created using Regeneron’s
VelocImmune® platform and associated VelociSuite® technologies. The treatment consists of three monoclonal antibodies that help neutralize the Ebola virus by blocking its ability to invade a patient’s cells and/or enlisting other immune cells to target infected cells and remove them from the body.
The safety and efficacy of Inmazeb was established through the 681-patient PALM Trial, which was independently conducted by the WHO, the U.S. National Institutes of Health and the INRB during the 2018 DRC outbreak of Ebola virus. In 2019, as reported in the New England Journal of Medicine, the PALM Trial was stopped early following a pre-specified interim analysis that showed the superiority of Inmazeb in preventing death versus two other investigational treatments.
Inmazeb was approved by the FDA in 2020, and in 2022, WHO published its first guidelines for Ebola virus therapeutics, which strongly recommends the use of Inmazeb for treatment of Ebola virus infection and calls on the global community to engage all possible mechanisms to improve access to life-saving Ebola disease medicines. In November 2023, Inmazeb became the first and only Ebola disease treatment to be prequalified by the WHO, certifying that the medicine meets WHO’s standards for quality, safety and efficacy and is considered “essential.”
Since 2018, Inmazeb has been offered by Regeneron at no cost under a compassionate use protocol to infected persons in countries experiencing an Ebola virus disease outbreak caused by Orthoebolavirus zairense, including the DRC and Guinea. In September 2025, the company committed to donate up to 500 doses of Inmazeb to the WHO for exclusive use by governments of low- and lower-middle income countries that are most at-risk for Ebola disease outbreaks.1 In addition, Regeneron has worked with governments in higher- and middle-income countries to establish Inmazeb stockpiles.
This project has been supported in whole or in part with federal funds from the U.S. Department of Health and Human Services
; Administration for Strategic Preparedness and Response; Biomedical Advanced Research and Development Authority
(BARDA), under contract numbers HHSO100201700016C and HHSO100201500013C. The contract and federal funding are not an endorsement of the product or company.
About Regeneron
Regeneron (NASDAQ: REGN) is a leading biotechnology company that invents, develops and commercializes life-transforming medicines for people with serious diseases. Founded and led by physician-scientists, our unique ability to repeatedly and consistently translate science into medicine has led to numerous approved treatments and product candidates in development, most of which were homegrown in our laboratories. Our medicines and pipeline are designed to help patients with eye diseases, allergic and inflammatory diseases, cancer, cardiovascular and metabolic diseases, neurological diseases, hematologic conditions, infectious diseases, and rare diseases.
Regeneron pushes the boundaries of scientific discovery and accelerates drug development using our proprietary technologies, such as VelociSuite®, which produces optimized fully human antibodies and new classes of bispecific antibodies. We are shaping the next frontier of medicine with data-powered insights from the Regeneron Genetics Center® and pioneering genetic medicine platforms, enabling us to identify innovative targets and complementary approaches to potentially treat or cure diseases. For more information, please visit www.Regeneron.com or follow Regeneron on LinkedIn, Instagram, Facebook or X.