The U.S. Food and Drug Administration’s (FDA) Vaccines and Related Biological Products Advisory Committee (VRBPAC) unanimously voted 19-0 to recommend emergency use authorization (EUA) for a booster dose of the Johnson & Johnson COVID-19 vaccine for adults aged 18 and older at least two months following initial vaccination with the single-shot vaccine, according to a news release from Johnson & Johnson.
The vote was based on findings from two clinical trials, including the Phase 3 ENSEMBLE 2 study, which evaluated a booster dose of the Johnson & Johnson COVID-19 vaccine administered two months after the single-shot, as well as a large and robust real-world evidence study. The company also presented data that support the increased potential of a booster when administered at six months. Phase 3 clinical data and real-world data both demonstrated the Johnson & Johnson single-shot COVID-19 vaccine was strong and long-lasting.
The company’s EUA amendment submission included results from the Phase 3 ENSEMBLE 2 study, which found a booster dose at two months provided 94% protection against symptomatic (moderate to severe/critical) COVID-19 in the United States and 100% protection against severe/critical COVID-19, at least 14 days post-booster vaccination. Also submitted were findings from a Phase 1/2a study evaluating a booster dose given six months after the first shot, which show antibody levels increased nine-fold one week after the booster and continued to climb to 12-fold higher four weeks after the booster.
The submission also included data from a large and robust U.S. real-world evidence study, conducted from March to July 31, 2021, and recently extended to August 31, 2021. These real-world data demonstrated the single-dose Johnson & Johnson COVID-19 vaccine showed stable vaccine effectiveness of 76% for COVID-19-related infections and 81% for COVID-19-related hospitalizations, with no evidence of reduced effectiveness over the study duration of six months — including when the Delta variant became dominant in the United States.
The Johnson & Johnson single-shot COVID-19 vaccine, developed by its subsidiary, Janssen Pharmaceutical Companies, received initial EUA in the United States on February 27.
