Pfizer Inc. and German partner BioNTech SE said Wednesday they have started a Phase 2 study to evaluate an enhanced COVID-19 vaccine aimed at the original strain of the virus and the omicron variant that seeks to create a more robust and longer-lasting immune response. The new bivalent vaccine called BNT162b5 will be tested in a randomized, active-controlled, observer-blind Phase 2 study to evaluate the safety, tolerability, and immune response. The study will be U.S.-based and involve about 200 participants aged 18 to 55, who have received one booster dose of a U.S.-authorized vaccine at least 90 days prior to their first study visit. The study will not include a placebo. “This is the first of multiple vaccine candidates with an enhanced design which the companies plan to evaluate as part of a long-term scientific COVID-19 vaccine strategy to potentially generate more robust, longer-lasting, and broader immune responses against SARS-CoV-2 infections and associated COVID-19,” the companies said in a joint statement. The move comes as health experts say the next generation of vaccines need to offer greater protection against infection, and not just severe disease and death. BioNTech shares rose 0.8% premarket, while Pfizer shares were flat.

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