Nov 8 (Reuters) - Regeneron Pharmaceuticals Inc (REGN.O) said on Monday a single dose of its antibody cocktail reduced the risk of contracting COVID-19 by 81.6% in a late-stage trial, in the two to eight months period following the drug"s administration. Shares of the company were up about 1.2% on the update as the data is expected to support the ongoing regulatory review to extend therapy"s use in preventing COVID-19 in people who are not exposed to the virus. The antibody therapy, REGEN-COV, is currently authorized in the United States to treat people with mild-to-moderate COVID-19 and for prevention of infection in those exposed to infected individuals, and others at high risk of exposure in settings such as nursing homes or prisons. read more The extended authorization could help boost sales of Regeneron"s antibody cocktail, in the face of competition from oral COVID-19 pills such as those being developed by Pfizer Inc (PFE.N) and Merck & Co (MRK.N).Data showed that Regeneron"s drug has the potential to provide long-lasting immunity from COVID-19 infection, said Myron Cohen, who leads monoclonal antibody efforts for the U.S. National Institutes of Health-sponsored COVID Prevention Network, making it particularly helpful for immunocompromised people and those unresponsive to vaccines. "With infections still occurring despite widespread vaccination, the immunocompromised face an ongoing risk of encountering the virus during their daily lives," Regeneron Chief Scientific Officer George Yancopoulos said. During the 8-month assessment period, there were no hospitalizations for COVID-19 in the REGEN-COV group, but in the placebo group 6 such incidents were recorded, Regeneron said. Regeneron said researchers were able to demonstrate the impact of its drug even after the immediate risk of household infection had subsided. It intends to rapidly share the additional data with regulatory authorities.