LOS ANGELES -- The COVID-19 vaccines made by Pfizer and Moderna both require two doses to be administered, several weeks apart, for them to be fully effective. But there has been some scientific ...

Pfizer Inc.’s covid-19 vaccine remained highly effective after six months, according to new long-term results that the company said could be used to seek an expansion of its regulatory status.

(Reuters) – The first dose of Pfizer Inc and BioNTech’s COVID-19 vaccine is 85% effective, a study of Israeli healthcare workers published in The Lancet https ...

Despite a U.S. factory mixup, more Johnson & Johnson doses are becoming available in the U.S., marking the only single-shot vaccine option. So how effective is it and how does it compare to the Pfizer ...

LOS ANGELES - Following the recent emergency approval by U.S. regulators for a coronavirus vaccine from Johnson & Johnson which contains a single-dose regimen, some medical experts are saying one dose ...

In a new document posted ahead of a key meeting of the US Food and Drug Administration's vaccine advisers, Pfizer says its vaccine is safe and 90.7% effective against symptomatic Covid-19 in children ...