BENGALURU (REUTERS) - Regeneron Pharmaceuticals Inc said on Monday (Nov 8) a single dose of its antibody cocktail reduced the risk of contracting Covid-19 by 81.6 per cent in the two to eight months period following the drug's administration in a late-stage trial.

The results showed that antibody therapy, REGEN-COV, has the potential to provide long-lasting immunity from Covid-19 infection, said Myron Cohen, who leads monoclonal antibody efforts for the US National Institutes of Health-sponsored Covid-19 Prevention Network.

Such immunity is particularly important for immunocompromised people and those not responding to vaccines, the company said.

The therapy had previously shown an 81.4 per cent risk reduction during the first month after administration.

During the eight-month assessment period, there were no hospitalisations for Covid-19 in the REGEN-COV group, but in the placebo group six such incidents were recorded, Regeneron said.

The US health regulator in July expanded REGEN-COV's authorisation to enable its use as a preventive treatment in people exposed to infected individuals, and those at high risk of such exposure in settings such as nursing homes or prisons.

It was authorised in the United States last November to treat people with mild-to-moderate Covid-19 disease.