Pfizer Inc. said it had asked U.S. regulators to expand access to its Covid-19 booster shot to all adults, and submitted data from a large trial showing that an additional dose is safe and highly effective at preventing infection. The pharmaceutical giant and partner BioNTech SE said in a statement on Tuesday that they had requested that the Food and Drug Administration amend the shot’s existing emergency-use authorization and extend eligibility for a third dose to everyone 18 and older. The partners shared data from a more than 10,000-person late-stage study evaluating the safety and efficacy of a booster dose administered to participants who had received two doses at least 6 months prior. The trial launched in the U.S., Brazil and South Africa among people 16 and older this past summer as cases caused by the delta variant surged. Findings from the trial demonstrated a relative vaccine efficacy of 95% when compared with those who didn’t get a booster, the companies said. Pfizer shares fell 2.1% to $47.30 at 4 p.m. in New York. BioNTech’s American depositary receipts declined 6.7%. View More……