J & J single-shot vaccine has 75% efficacy but boosters required

eAwaz Medicine

NEW BRUNSWICK -The largest real-world evidence study for a COVID-19 vaccine reported to date in the U.S. demonstrated stable vaccine effectiveness of 79 percent (CI, 77%-80%) for COVID-19-related infections and 81 percent (CI, 79%-84%) for COVID-19-related hospitalizations. There was no evidence of reduced effectiveness over the study duration, including when the Delta variant became dominant in the U.S. Sequencing data were not available for analysis. The study included 390,000 people who received the Johnson & Johnson COVID-19 vaccine versus approximately 1.52 million unvaccinated people matched on age, sex, time, three-digit zip code, and comorbidities and predictors for COVID-19 infection severity conducted from March to late July 2021.

These data were consistent with the Phase 3 ENSEMBLE trial, where strong protection against severe/critical disease and death was observed at least 28 days post-final vaccination:

  • 75 percent overall efficacy (CI, 65%-82%) against severe/critical COVID-19, across all age cohorts and all countries included in the study.
  • 74 percent efficacy in the U.S. against severe/critical COVID-19 (CI, 39%-91%); 89 percent against hospitalization (CI, 24%-100%); 83 percent against COVID-19-related death (CI, 41%-97%).

Booster shot at two months provided 94 percent protection against COVID-19 in the U.S.
The Phase 3 ENSEMBLE 2 study showed that another shot of the Johnson & Johnson COVID-19 vaccine given 56 days after the first provided:

  • 100 percent protection (CI, 33%-100%) against severe/critical COVID-19 – at least 14 days post-final vaccination.
  • 75 percent protection against symptomatic (moderate to severe/critical) COVID-19 globally (CI, 55%-87%).
  • 94 percent protection against symptomatic (moderate to severe/critical) COVID-19 in the U.S. (CI, 58%-100%).

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.

Booster shot at six months provided 12-fold increase in antibodies
When a booster of the Johnson & Johnson COVID-19 vaccine was given six months after the single shot, antibody levels increased nine-fold one week after the booster and continued to climb to 12-fold higher four weeks after the booster. All rises were irrespective of age.

The Johnson & Johnson single-shot COVID-19 vaccine, developed by its Janssen Pharmaceutical Companies of Johnson & Johnson, received an Emergency Use Authorization (EUA) in the United States on February 27, 2021 and Conditional Marketing Authorization (CMA) by the European Commission on March 11. The World Health Organization (WHO) issued Emergency Use Listing on March 12, and the Company received an interim recommendation by the Strategic Advisory Group of Experts (SAGE) on Immunization for the WHO on March 17. Many more authorizations have been granted in countries worldwide, and regulatory submissions are ongoing.