FDA committee backs Novavax's COVID-19 vaccine despite heart damage concerns

Is the Novavax COVID-19 vaccine associated with a risk of myocarditis, pericarditis or other cardiac events?

In an 80-page briefing document, the FDA noted that six cases of myocarditis/pericarditis were seen in patients receiving the vaccine. These cases, the agency wrote, are “of particular interest” and “similar to myocarditis following mRNA COVID-19 vaccines.” Four patients were young men; the remaining two patients were a 60-year-old woman and 67-year-old man. Five of the six patients were hospitalized.

One case of myocarditis was also seen in a 31-year-old woman who received a placebo.

In addition, the FDA highlighted other potential cardiovascular concerns in its briefing document.

“Review of the data also identified small imbalances in certain thromboembolic events, including cardiac and neurovascular events, hypersensitivity events, cholecystitis, uveitis, cardiac failure and cardiomyopathy,” according to the agency “However, a causal association between vaccination and these events cannot be concluded based on available data. Subgroup analyses of safety data did not reveal any notable differences across demographic groups.”

Novavax issued a separate statement about these concerns.

“We have learned that we can expect to see natural background events of myocarditis in any sufficiently large database, and that young males are at higher risk,” according to the statement. “Myocarditis is most often caused by nonspecific viral infections. The data from our placebo-controlled studies show that overall, in our clinical development program, the rate of myocarditis was balanced between the vaccine and placebo arms. Furthermore, in the post-crossover portions of our studies, the cases we have seen are all within the expected rate.”