Regeneron’s COVID-19 cocktail gets FDA emergency use authorization

The Food and Drug Administration has granted emergency use authorization for Regeneron Pharmaceuticals’ antibody cocktail casirivimab and imdevimab administered together (formerly known as REGN-COV2 or REGEN-COV2).

Casirivimab and imdevimab administered together are authorized for the treatment of mild to moderate COVID-19 in adults, as well as in pediatric patients at least 12 years of age and weighing at least 40 kg, who have received positive results of direct SARS-CoV-2 viral testing and are at high risk for progressing to severe COVID-19 and/or hospitalization.

The clinical evidence from Regeneron’s outpatient trial suggests that monoclonal antibodies such as casirivimab and imdevimab have the greatest benefit when given early after diagnosis and in patients who have not yet mounted their own immune response or who have high viral load.

Casirivimab and imdevimab are not authorized for use in patients who are hospitalized or require oxygen therapy due to COVID-19, or for people currently using chronic oxygen therapy because of an underlying comorbidity who require an increase in baseline oxygen flow rate due to COVID-19. 

“This FDA Emergency Use Authorization is an important step in the fight against COVID-19, as high-risk patients in the United States will have access to a promising therapy early in the course of their infection,” said Leonard Schleifer, president and CEO of Regeneron. “The science and technology investments Regeneron has made over three decades positioned us to move rapidly to invent, study and maximize production of our antibody cocktail. Even with these incredible efforts, demand may exceed supply initially, making it even more critical that federal and state governments ensure the casirivimab and imdevimab antibody cocktail is distributed fairly and equitably to the patients most in need. In the first quarter of 2021, we expect to increase available global supply as we continue our collaboration with Roche.”

“The casirivimab and imdevimab antibody cocktail is designed to mimic what a well-functioning immune system does by using very potent antibodies to neutralize the virus,” said George Yancopoulos, president and chief scientific officer of Regeneron.

Yancopoulos continued, “Data from approximately 800 non-hospitalized patients showed significant reductions in virus levels within days of receiving the combination, which were associated with significantly fewer medical visits. This benefit was greatest in patients most at risk for poor outcomes due to high viral load, ineffective immune response at baseline or pre-existing risk factors. We are encouraged that no variants resistant to the cocktail were identified in the clinical trial analyses to date, which is consistent with our preclinical findings. We are also very encouraged by recently announced promising vaccine results; however, there remains a need to treat patients who develop COVID-19, especially as some may not have had access to or were not protected by vaccination. Importantly, we continue to advance our rigorous clinical trial program evaluating the safety and efficacy of the antibody cocktail for both the treatment and prevention of COVID-19, and we will share new results as available.”

Regeneron now expects to have treatment doses ready for approximately 80,000 patients by the end of November, approximately 200,000 patients by the first week of January, and approximately 300,000 patients in total by the end of January 2021.

As part of Operation Warp Speed, in July the U.S. government and Regeneron signed an agreement for this initial supply of the casirivimab and imdevimab antibody cocktail. The U.S. government will coordinate with state authorities to allocate the antibody cocktail on a weekly basis based on the number of COVID-19 cases in each state. The government has committed to providing these 300,000 doses at no cost to patients, although healthcare facilities may charge fees related to administration. Regeneron will immediately begin shipping doses to Amerisource Bergen, which will distribute the therapy as directed by the government, the company said.