myocarditis with the Novavax vaccine
WASHINGTON (awp/afp) – The United States Medicines Agency (FDA) expressed concern on Friday about a risk of myocarditis potentially linked to the Novavax Covid-19 vaccine, before a meeting of experts to decide the week next on the authorization of this remedy in the United States.
The Novavax vaccine is already authorized in other countries, particularly in Europe.
In the United States, an independent committee convened at the request of the FDA is to meet on Tuesday to evaluate the data from the clinical trials of Novavax and give its recommendation. Upstream, the agency published a long document on Friday analyzing these results, as it had done for the three other vaccines already authorized in the country.
The title of Novavax has in the wake collapsed by 20% on the New York Stock Exchange.
Novavax’s vaccine was found to be 90% effective against symptomatic cases of the disease, in trials conducted before the appearance of the Omicron variant, according to the FDA.
But six cases of myocarditis, inflammation of the heart muscle, were detected in the group that received the vaccine, against one case in the placebo group, the agency pointed out. Five cases occurred within two weeks of vaccination.
“The identification of several potentially vaccine-associated cases,” out of 40,000 clinical trial participants, “raises concern that if a causal link exists, the risk of myocarditis following vaccination with NVX-CoV2373 may be higher than that which has been reported during the post-licensing period of messenger RNA vaccines,” the FDA said in its analysis.
The risk of myocarditis has indeed been identified after vaccination with Pfizer or Moderna, particularly in young men and adolescent boys. But the FDA recalled that during clinical trials of these vaccines, no cases had yet been detected. She seems to be worried that this risk is higher with Novavax.
The company issued a response statement on Friday: “We believe there is insufficient evidence to establish a causal relationship” between the myocarditis cases and the vaccine, she said, adding that it was normal “to expect to see a number of myocarditis” occurring in the population anyway “in any large enough database”.
the/led