** Shares of Pfizer Inc rise ~1% to $43.2 premarket
** Co says a late-stage study with 10,000 participants showed high efficacy of a booster dose of its COVID-19 vaccine against the virus, including the Delta variant
** The co and its German partner BioNTech also say research conducted in Israel shows that their COVID-19 vaccine is highly effective at preventing infection and symptomatic disease from the Delta variant among 12- to 18-year-olds.
** U.S. regulators have already authorized a third dose of PFE/BNTX's COVID-19 vaccine at least six months after the first round of shots, for people aged 65 and older and those at risk of severe disease
** Up to Wednesday's close, PFE up ~16.4% YTD
(Reporting by Manojna Maddipatla in Bengaluru) ((firstname.lastname@example.org; +91 8061822700;))