Regeneron Sees Promising Results for Antibody Cocktail vs. COVID-19 in Animals

NEW YORK – Regeneron Pharmaceuticals Inc said on August 3 that “the COVID-19 antibody drug combination it is developing both prevented and treated the disease in rhesus macaques and hamsters, adding to hope that it might work for people,” Reuters reported.

The U.S. biotech company said “in the animal study, which has not yet been peer reviewed, that the cocktail of two monoclonal antibodies was able to ‘almost completely block establishment of virus infection,’” Reuters reported.

Regeneron said “the cocktail was also able to minimize infection in a second study in which animals were infected with a much higher level of the virus,” Reuters reported, adding that “the prophylactic effect was greatly diminished with a lower dose of the drug, the company said.”

According to Regeneron, “the results matched or exceeded effects recently shown in animal studies of vaccine candidates,” Reuters reported.

“The infected animals treated with the antibodies cleared the virus faster than those given a placebo,” the company said, Reuters reported, adding that “the lead researchers said the data suggests the therapy may offer clinical benefit in both prevention and treatment of COVID-19,” and “they also said the animals did not show any signs of increased viral load or worsening of pathology after treatment, an important safety signal that suggests it will not worsen symptoms in humans.”

“The studies were conducted on a total of 36 rhesus macaques and 50 hamsters,” Reuters reported, noting that “positive results in animals are no guarantee of success in humans.”

Regeneron “has already started late-stage clinical trials in humans to assess the antibody treatment’s ability to prevent and treat COVID-19,” Reuters reported, adding that “the company signed a $450 million contract with the U.S. government as part of its Operation Warp Speed program to provide the United States with the treatment if it succeeds.”

Greek-American Dr. George D. Yancopoulos, Co-Founder, President and Chief Scientific Officer of Regeneron, had told The National Herald in an interview in March about the effort to develop the antibody cocktail in the fight against COVID-19, and noted even then that trials could begin as early as June.

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.

More information about Regeneron is available online: www.regeneron.com or follow @Regeneron on Twitter.


NEW YORK – Dr. Macrene Alexiades was featured in Vogue magazine for reconnecting with her Greek heritage and “her vision of natural skin care” after building a home on the island of Skyros.

Top Stories


A pregnant woman was driving in the HOV lane near Dallas.

General News

FALMOUTH, MA – The police in Falmouth have identified the victim in an accident involving a car plunging into the ocean on February 20, NBC10 Boston reported.

General News

NEW YORK – Meropi Kyriacou, the new Principal of The Cathedral School in Manhattan, was honored as The National Herald’s Educator of the Year.


Enter your email address to subscribe

Provide your email address to subscribe. For e.g. [email protected]

You may unsubscribe at any time using the link in our newsletter.