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# J&J Touts Vaccine Booster Data
- URL: https://www.fdaweb.com/j-j-touts-vaccine-booster-data/
- Published: 2021-09-21T12:00:00.000Z
- Updated: 2026-09-14T17:15:25.000Z
- Author: David McFarland
- Tags: Drugs, #legacy-id-D5150190

Johnson & Johnson says new data show increased protection against Covid-19 when a booster shot of its vaccine is administered, adding that the vaccine’s safety profile remained consistent after the booster shot. The company says a [real-world evidence study](https://www.medrxiv.org/content/10.1101/2021.09.10.21263385v2?ref=fdaweb.com) for its vaccine demonstrated 79% effectiveness for Covid-19-related infections and 81% for Covid-related hospitalizations. Data also showed that a booster given 56 days after the first dose provided 100% protection against severe/critical Covid-19, and 94% protection against symptomatic (moderate to severe/critical) Covid-19 in the U.S. “When a booster of the Johnson & Johnson Covid-19 vaccine was given two months after the first shot, antibody levels rose to four to six times higher than observed after the single shot,” it says, adding that when a booster was given six months after the first dose, antibody levels were 12-fold higher four weeks after the booster. The data are being submitted to FDA for review.