The FDA completed review of the vaccine, now marketed as Comirnaty, in just over three months, or some 40% faster than usual, Marks said. During the review process, the FDA evaluated updated clinical trial data on vaccine efficacy among 40,000 participants aged 16 years and older, half of whom received a placebo. Trial results indicated the vaccine was 91% effective in preventing COVID-19 disease, though data will continue to be monitored as real-world evidence suggests waning immunity over time.
The FDA also evaluated vaccine safety among 44,000 trial participants aged 16 and older, with available follow-up safety data extending at least four months post-second dose for over half of trial participants. The most common side effects among participants included pain, redness and swelling at the injection site, fatigue, headache, muscle or joint pain, chills and fever. Data also demonstrated an increased risk of myocarditis, or heart inflammation, among males under 40, with males aged 12-17 facing the highest observed risk. However, available data suggest most patients’ symptoms have resolved, Marks said.