Johnson & Johnson’s Booster Shot Prevents Severe Infection
- Added dose spurs Covid antibody production, aids protection
- J&J joins rivals showing booster benefits as delta circulates
A health worker prepares a dose of the Johnson & Johnson Covid-19 vaccine in Cape Town, South Africa.
Photographer: Dwayne Senior/BloombergThis article is for subscribers only.
A booster dose of Johnson & Johnson’s Covid-19 vaccine provided 100% protection against severe disease when given two months after the first inoculation, according to widely anticipated data that suggests it increases the potency of the one-time shot.
The booster was 94% effective at preventing symptomatic Covid infections in the U.S. portion of the Phase III trial, and 75% effective overall when it was given 56 days after the initial dose, the company said in a statement Tuesday. A second study found the additional shot spurred a 12-fold increase in production of antibodies against Covid when it was given six months after the first.