Pfizer’s Covid-19 vaccine’s efficacy erodes over time

Pfizer Inc. said that data from the US and Israel suggest that the efficacy of its Covid-19 vaccine wanes over time, and that a booster dose was safe and effective at warding off the virus and new variants. The company detailed the data in a presentation it will deliver to a meeting of outside advisers to the Food and Drug Administration on Friday. The panel is expected to make recommendations for whether more Americans should receive booster shots. “Real-world data from Israel and the United States suggest that rates of breakthrough infections are rising faster in individuals who were vaccinated earlier,” Pfizer said in its presentation.