Pfizer's Covid-19 vaccine trial data shows long-term efficacy in adolescents

Pfizer Inc said on Monday its Covid-19 vaccine provided strong long-term protection against the virus in a late-stage study conducted among adolescents aged 12 to 15 years.

A two-dose series of the vaccine was 100 percent effective against Covid-19, measured seven days through over four months after the second dose, the company said...