Clinical program consists of four separate study populations: two for treatment and two for prevention

First studies evaluate safety and efficacy in hospitalized and non-hospitalized patients with COVID-19

Two-antibody ‘cocktail’ is designed to help protect against viral escape

TARRYTOWN, NY, USA I June 11, 2020 IRegeneron Pharmaceuticals, Inc. (NASDAQ: REGN) today announced initiation of the first clinical trial of REGN-COV2, its investigational dual antibody cocktail for the prevention and treatment of COVID-19. The REGN-COV2 clinical program will consist of four separate study populations: hospitalized COVID-19 patients, non-hospitalized symptomatic COVID-19 patients, uninfected people in groups that are at high-risk of exposure (such as healthcare workers or first responders) and uninfected people with close exposure to a COVID-19 patient (such as the patient’s housemate). The placebo-controlled trials will be conducted at multiple sites.

“We have created a unique anti-viral antibody cocktail with the potential both to prevent and treat infection, and also to preempt viral ‘escape,’ a critical precaution in the midst of an ongoing global pandemic,” said George D. Yancopoulos, M.D., Ph.D., Co-Founder, President and Chief Scientific Officer of Regeneron. “REGN-COV2 could have a major impact on public health by slowing spread of the virus and providing a needed treatment for those already sick – and could be available much sooner than a vaccine. The antibody cocktail approach may also have long-term utility for elderly and immuno-compromised patients, who often do not respond well to vaccines. Ultimately, the world needs multiple solutions for COVID-19, and the innovative biopharma industry is collectively working hard to help as many people as possible with a variety of complementary approaches.”

Regeneron scientists evaluated thousands of fully-human antibodies produced by the company’s proprietary VelocImmune® mice, which have been genetically-modified to have a human immune system, as well as antibodies isolated from humans who have recovered from COVID-19. They selected the two most potent, non-competing and virus-neutralizing antibodies and have scaled them up for clinical use with the company’s in-house VelociMab® and manufacturing capabilities. The two antibodies bind non-competitively to the critical receptor binding domain (RBD) of the virus’s spike protein, which diminishes the ability of mutant viruses to escape treatment, as demonstrated in upcoming Science publications of preclinical research.

Regeneron used the same ‘rapid response’ capabilities and cocktail approach to develop REGN-EB3, a novel triple antibody treatment for Ebola that is now under regulatory review by the U.S. Food and Drug Administration (FDA). REGN-COV2’s preclinical development and preclinical/clinical manufacturing has been funded in part with federal funds from the Biomedical Advanced Research and Development Authority (BARDA), part of the office of the Assistant Secretary for Preparedness and Response at the U.S. Department of Health and Human Services, under OT number: HHSO100201700020C.

The first two adaptive Phase 1/2/3 studies are evaluating REGN-COV2 (REGN10933+REGN10987) as a treatment for hospitalized and non-hospitalized patients with COVID-19. The Phase 1 portion will focus on virologic and safety endpoints, and the Phase 2 portion will focus on virologic and clinical endpoints. Data from the Phase 1 and Phase 2 studies will be used to refine the endpoints and determine size for the Phase 3 studies.

“We are particularly excited to begin studies of REGN-COV2, which is a novel antibody cocktail targeted specifically against SARS-CoV-2,” said trial investigator Dr. Suraj Saggar, Chief of Infectious Disease at Holy Name Medical Center in Teaneck, New Jersey. “Over the last long months, we have learned that repurposing existing medicines unfortunately does not offer a broadly effective solution for COVID-19. For this reason, we need to investigate custom-designed approaches like REGN-COV2. The first studies will evaluate if REGN-COV2 can improve disease outcomes in both hospitalized and non-hospitalized patients with COVID-19.”

About Regeneron’s Anti-Viral Antibodies
When faced with a harmful pathogen, such as a virus or bacteria, the human immune system typically produces antibodies to fight the invader. Specifically, the immune system produces ‘anti-viral’ antibodies that recognize, bind, and kill or neutralize the virus. Vaccination involves injecting a dead or weakened virus, or a critical small piece of a virus, to induce this protective immune response, resulting in the same antibodies the immune system would typically make in a person who actually had the infectious disease.

Regeneron’s core technologies allow for rapid and efficient generation of these protective anti-viral antibodies outside of the body, derived from either genetically-humanized mice or convalescent humans. The resulting antibodies correspond to the most potent of anti-viral antibodies that could be elicited by a vaccine or through exposure to a pathogen. These antibodies can be delivered to people via injection, providing “passive immunity” and protection from the disease immediately, though they must be re-administered to remain effective over time. These antibodies can also treat an existing infection, unlike vaccines which can only be used preventatively.

The concept that drug cocktails can prevent viral escape has previously been demonstrated for traditional antiviral drugs used to treat HIV and other viruses. In the upcoming Science publications, Regeneron scientists report the fundamental realization that this can also be true for antibody-based therapies. Regeneron’s preclinical studies demonstrate that, in the setting of a single therapeutic antibody that blocks the ability of a virus to infect healthy cells, spontaneously arising mutant forms of the virus are able to ‘escape’ or evade the antibody’s blocking action. These mutants are then ‘selected’ (i.e., are able to survive and proliferate despite the single antibody treatment) and may ultimately become the dominant strain of the virus. Regeneron therefore pursues a multi-antibody cocktail approach designed to decrease the potential for the virus to escape.

Regeneron has developed additional technologies that allow for the large-scale manufacturing and purification of these anti-viral antibodies, potentially allowing many people to be granted immunity before vaccines become widely available.

About Regeneron
Regeneron (NASDAQ: REGN) is a leading biotechnology company that invents life-transforming medicines for people with serious diseases. Founded and led for over 30 years by physician-scientists, our unique ability to repeatedly and consistently translate science into medicine has led to seven FDA-approved treatments and numerous product candidates in development, all 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, pain, infectious diseases and rare diseases.

Regeneron is accelerating and improving the traditional drug development process through our proprietary VelociSuite® technologies, such as VelocImmune® which uses unique genetically-humanized mice to produce optimized fully-human antibodies and bispecific antibodies, and through ambitious research initiatives such as the Regeneron Genetics Center, which is conducting one of the largest genetics sequencing efforts in the world. For additional information about the company, please visit www.regeneron.com or follow @Regeneron on Twitter.

SOURCE: Regeneron Pharmaceuticals