• REGN-EB3 developed via same rapid response platform currently being leveraged to develop novel COVID-19 antibody therapy

Regeneron Pharmaceuticals, Inc. (NASDAQ: REGN) today announced that the U.S. Food and Drug Administration (FDA) has accepted for Priority Review a new Biologics License Application (BLA) for REGN-EB3, an investigational triple antibody cocktail treatment for Ebola virus infection. The target action date for the FDA decision is October 25, 2020.

The REGN-EB3 BLA is supported by data from the randomized, controlled PALM clinical trial conducted in the Democratic Republic of Congo. In August 2019, the trial was stopped early when preliminary results showed that REGN-EB3 crossed the pre-specified superiority threshold for preventing death compared to the control arm, ZMapp. REGN-EB3 demonstrated superior efficacy compared to ZMapp across multiple measures, including reduced mortality and fewer days until the Ebola virus was no longer detected in the bloodstream.

"Developed using Regeneron's proprietary VelociSuite^® rapid response technologies, REGN-EB3 was shown to save lives in the PALM trial, which evaluated multiple therapies against the current standard of care," said George D. Yancopoulos, M.D., Ph.D., Co-Founder, President and Chief Scientific Officer of Regeneron. "Regeneron is now applying this same approach to develop an antibody medicine that can potentially prevent and treat COVID-19, with initial clinical trials expected to begin in June."

Regeneron's VelociSuite technologies enable the efficient creation and selection of potent fully-human antibodies against a specific biological target, which is particularly critical for addressing new and/or quickly-spreading pathogens such as Ebola and COVID-19. These technologies facilitate the rapid cloning and generation of optimized fully-human antibodies from both VelocImmune^® mice (which are genetically-engineered to have genetically-humanized immune systems) and convalescing human volunteers, and allow for the rapid escalation of fully-human antibodies into manufacturing-quality cell line production and large-scale bioreactor manufacturing. Once strong therapeutic antibody candidates are identified, the company's in-house preclinical, clinical and commercial-scale manufacturing capabilities allow for fast scale-up and flexibility to adapt to current need.

REGN-EB3 has received Orphan Drug and Breakthrough Therapy designation from the FDA. It is being developed under an ongoing collaboration and with funding provided by the Biomedical Advanced Research and Development Authority (BARDA), part of the office of the Assistant Secretary for Preparedness and Response within the U.S. Department of Health and Human Services (USG Contract Nos. HHSO100201700016C and HHSO100201500013C).

Contacts:

Media Relations
Alexandra Bowie
Tel: +1 (914) 847-3407
alexandra.bowie@regeneron.com

Investor Relations
Mark Hudson
Tel: +1 (914) 847-3482
mark.hudson@regeneron.com