Regeneron's COVID-19 antibody-drug cocktail treats SARS-CoV-2 virus in animals

By Angela Betsaida B. Laguipo, BSNAug 5 2020

The coronavirus pandemic is actively wreaking havoc across the globe, with more than 18.54 million confirmed cases. There is still no vaccine for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) or specific treatment for the coronavirus disease (COVID-19). However, the race toward developing an effective vaccine and treatment is on, but it may take months or even years before a vaccine or drug is approved.

Now, Regeneron Pharmaceuticals says its COVID-19 antibody-drug cocktail under development prevented and treated the disease in monkeys and hamsters, showing promise that it may work in humans.

Colorized scanning electron micrograph of a cell (purple) infected with SARS-CoV-2 virus particles (yellow), isolated from a patient sample. Image captured at the NIAID Integrated Research Facility (IRF) in Fort Detrick, Maryland. Credit: NIAID

The study

The company's cocktail of two monoclonal antibodies, called the REGN-COV-2, was able to prevent and treat the disease in rhesus macaques and hamsters.

Further, the scientists behind the project said the animals did not show any signs of increased viral load or worsening conditions after treatment.

The U.S. biotech company said that the animal study, which has not yet been peer-reviewed, showed that the two monoclonal antibodies were able to almost completely block the establishment of virus infection. The researchers also said the drugs were able to reduce infection in a second study in which the animals were infected with a higher level of the virus.

The company said that the infected animals treated with REGN-COV2 cleared the virus faster than those who were given a placebo. The data suggests that the therapy may offer clinical benefit in both the prevention and treatment of COVID-19.

Promising results

Regeneron Pharmaceuticals announced earlier in July that it has been awarded a $450 million contract with the U.S. government, as part of its Operation Warp Speed program, to manufacture and supply REGN-COV2, the company's investigational double-antibody cocktail that is being trialed as a treatment for COVID-19.

"Regeneron's thirty years of investment in our innovative VelociSuite® antibody discovery and development technologies and our large-scale manufacturing facilities, coupled with the expertise and passion of our people, has enabled us to move the REGN-COV2 program forward at remarkable speed," Dr Leonard S. Schleifer, Co-Founder, President and Chief Executive Officer of Regeneron, said in a statement.

"We made the decision early on to begin large-scale manufacturing at our own risk to ensure that product would be available immediately if our clinical trials prove successful and an Emergency Use Authorization is granted. This manufacturing and supply agreement with BARDA and the Department of Defense could help REGN-COV2 reach many people quickly, hopefully helping to change the course of this deadly and still-raging pandemic," he added.

What is REGN-COV2?

Scientists at Regeneron studied thousands of fully-human antibodies produced by laboratory mice, called the VelovImmune. These mice were genetically engineered to have a human immune system with antibodies identified from humans who have recovered from the novel coronavirus infection.

The team chose two of the most potent, robust, and virus-neutralizing antibodies to produce REGN-COV2. To work, the drug bind to the receptor-binding domain (RBD) of the virus's spike protein, reducing the ability of the virus to evade treatment and protects against spike variants that have emerged in the human population.

The company used the same technique and cocktail approach to develop REGN-EB3, a novel antibody treatment for Ebola, which is now being reviewed by the Food and Drug Administration (FDA).

COVID-19 global toll

The coronavirus pandemic has so far killed more than 700,000 worldwide. The United States and Brazil remain as the countries with the highest number of cases, at more than 4.77 million and 2.8 million, respectively.

The death toll in the U.S. has topped 156,000, while Brazil trails behind, with at least 95,000 deaths. India, Russia, South Africa, and Mexico report an increasing number of cases, with more than 1.9 million, 859,000, 521,000, and 449,000 confirmed cases, respectively.

The epicenter of the pandemic has moved from Europe to the United States and South America. Brazil, Peru, Chile, and Colombia have skyrocketing cases.