J&J’s single-dose vaccine review was released today by the FDA committee. This review is an advisory document to brief the FDA’s Vaccines and Related Biological Products Advisory Committee.
While this vaccine may not have produced the remarkable protection of the mRNA vaccines from Pfizer and Moderna, it was still strongly endorsed by the FDA reviewers. They believe that it could provide robust protection, particularly against severe COVID-19 disease.
The FDA confirmed that in a trial of just under 40,000 volunteers, the vaccine was 66% effective at preventing symptomatic Covid-19, 72% effective in the United States, presumably due to presence of fewer variant viruses. This means that the number of infections in the 20,000 immunized people was 66% less than in the 20,000 controls.
Although that’s significantly less than the 95% protection from either the Moderna or Pfizer-BioNTech vaccines, the J&J shot was 85% effective at stopping severe disease 28 days after administration. Mortality was also eliminated as there were seven deaths in the placebo group but none in the vaccine group.
There was evidence that the immune response strengthened over time, as infections stopped eventually over time, but the study showed protection began after just 14 days.
My guess is that this vaccine will show even better efficacy in the two dose trials currently underway. This certainly provides another option at a time of vaccine shortages!