Pharmaceuticals said on Tuesday that its antibody cocktail was effective in preventing Covid-19 in people exposed to people infected with the new coronavirus, based on provisional results from a final-stage study.
The cocktail of two antibodies, REGEN-COV, caused a 100 percent reduction in symptomatic infection and overall infection rates about 50 percent lower, based on an analysis of about 400 study participants who had a member of the family with Covid-19.
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Regeneron said it would discuss the interim results with US health regulators to expand the current emergency use authorization (USA) of the antibody cocktail. The full data from the trial is expected at the beginning of the second quarter.
In November, the US Food and Drug Administration granted the USA the antibody cocktail for the treatment of mild to moderate Covid-19 in adults and children.
The current trial tested REGEN-COV for use as a passive vaccine, which involves the direct delivery of anti-virus antibodies to the body, unlike traditional vaccines in which the recipient’s immune system is activated to develop its own antibodies.
REGEN-COV may be able to provide immediate passive immunity for those at high risk for infection, in contrast to active vaccines that take weeks to provide protection, the company said.
“This data using REGEN-COV as a passive vaccine suggests that it can reduce transmission of the virus, as well as reduce viral load and disease in those who are still infected,” said George Yancopoulos, president and chief scientific officer of Regeneron.
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The drugmaker also hopes that REGEN-COV will help people who respond poorly to vaccination.
During the trial, performed jointly by Regeneron and the National Institute of Allergy and Infectious Diseases, a death and hospitalization related to Covid-19 was reported among those who received a placebo, but there was no such incident in the treatment group, the company said. .
REGEN-COV is also being studied in two final-stage clinical trials of hospitalized patients and an advanced-stage clinical trial for the treatment of out-of-hospital patients.
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