Regeneron's COVID-19 Cocktail Helps Prevent Symptomatic Disease

Regeneron will seek U.S. approval for its COVID-19 antibody cocktail as a preventative treatment after a trial showed it helped reduce the risk of symptomatic infections in households where someone else is ill, the U.S. drugmaker said on Monday.

REGEN-COV, as the combination shot of casirivimab and imdevimab is called, reduced the overall risk of progressing to symptomatic COVID-19 by 31%, and by 76% after the third day. The trial also demonstrated that it shortened symptom duration and markedly lowered viral levels, Regeneron said in a statement.

Regeneron has enlisted Switzerland's Roche and its massive biotech facility in South San Francisco to help make around 2 million doses annually, a substantial amount although only a fraction of what would be needed to cover the people who get the illness, which is currently infecting about 3.5 million people weekly worldwide.

The drug has emergency U.S. approval for mild to moderate COVID-19 patients, and the companies are hoping the latest trial convinces regulators to expand its deployment. European regulators have voiced some support and are letting countries decide if they want to use it.

"These data pave the way for REGEN-COV to be used before patients become symptomatic, with a more convenient subcutaneous administration," Katharine Bar, co-principal investigator and a professor at the University of Pennsylvania hospital, said in Regeneron's release.

Regeneron said its trial met primary and key secondary endpoints: Beyond reducing symptomatic infection risk, the total number of weeks patients experienced symptoms was nearly halved (45%) with REGEN-COV, and the viral burden was cut by 90%-plus, potentially helping halt the disease's spread.

Regeneron booked around $260 million in U.S. government orders for the drug in the first quarter. Roche has not given financial projections for sales outside the United States.