For at least eight months following a single dose, the REGEN-COV COVID-19 drug cocktail developed by Regeneron Pharmaceuticals, Inc. could provide affiliated risk reductions of 81.6 percent, according to a new analysis of a Phrase 3 trial.
That trial, jointly run by Regeneron and the National Institute of Allergy and Infectious Diseases (NIAID), indicated that the 1,200 mg mix of casirivimab and imedivimab was also able to cut severe, hospitalized cases of COVID-19 entirely from the mix. Tests were conducted on uninfected individuals, and then researchers charged any lab-confirmed symptomatic SARS-CoV-2 infections that cropped up in the months following.
“Today’s new data demonstrate how a single dose of REGEN-COV can help protect people from COVID-19 for many months after administration,” said Dr. Myron Cohen., lead for monoclonal antibody efforts at the COVID Prevention Network (CoVPN) and director of the Institute for Global Health & Infectious Diseases at the University of North Carolina at Chapel Hill. “These results demonstrate that REGEN-COV has the potential to provide long-lasting immunity from SARS-CoV-2 infection, a result particularly important to those who do not respond to COVID-19 vaccines including people who are immunocompromised.”
The results build on those previously published in the New England Journal of Medicine, which found that REGEN-COV reduced risk by 81.4 percent during the first month after administration. The cocktail utilizes fully human antibodies to do its work, with no artificial mutations or sequencing to achieve its results.
“In this trial, a single dose of REGEN-COV provided long-term protection against COVID-19, including times of particularly high risk from household exposure, and in the longer-term during ongoing broader exposure,” Dr. GeorgeYancopoulos, president and Chief Scientific Officer at Regeneron, said. “These data add to the increasing body of evidence supporting use of REGEN-COV to prevent COVID-19 in uninfected individuals, which may be especially useful for the many immunocompromised people who do not respond adequately to vaccines and remain ‘prisoners of the pandemic.’ With infections still occurring despite widespread vaccination, the immunocompromised face an ongoing risk of encountering the virus during their daily lives.”
Enrollment in the trial ended earlier this year. During the follow-up period, no new hospitalizations, deaths, or side effects emerged among those issued REGEN-COV, compared to six people hospitalized in the placebo group. The drug is currently authorized by the U.S. Food and Drug Administration to treat those at high risk of serious consequences from COVID-19 or those either already infected but not yet hospitalized or in specific post-exposure prophylaxis settings.
The U.S. federal government has partly funded the development and manufacturing of REGEN-COV, but Regeneron is also collaborating with Roche to increase supplies outside the United States.