FDA advisers recommend authorization of Novavax’s Covid-19 vaccine

Experts who advise the Food and Drug Administration voted overwhelmingly on Tuesday to recommend the agency issue an emergency use authorization for Novavax’s Covid-19 vaccine — a long-awaited win for a company that has struggled to get to this point.

The Vaccines and Related Biological Products Advisory Committee voted 21 to 0 to recommend that the vaccine receive an EUA, with a single abstention. The strong vote belied the tenor of much of the day’s discussion, which started with one member of the committee, Eric Rubin, editor of the New England Journal of Medicine, questioning whether additional EUAs are needed when three vaccines are already in use in the country.

The FDA does not have to follow VRBPAC’s advice, but it generally does. That would suggest Novavax’s Covid vaccine, which has already been authorized for use in more than 40 other countries, will become available in the United States sometime in the next few weeks.

“The advisory committee’s positive recommendation acknowledges the strength of our data and the importance of a protein-based Covid-19 vaccine developed using an innovative approach to traditional vaccine technology,” Stanley Erck, Novavax president and CEO, said in a statement.

“We have heard in today’s VRBPAC meeting the significant support for our vaccine from physicians, healthcare organizations, and consumers who are eagerly anticipating a protein-based vaccine option,” he said, referring to remarks made during a public comment session which heavily favored authorization of the vaccine and in some cases blamed the FDA for the vaccine’s slow progress to market.

Experts have long expressed hope for this vaccine, made using more traditional technology than the messenger RNA vaccines that have been in use since December 2020. But Novavax, which has never brought a vaccine through the licensure process before and which didn’t own a production plant when the pandemic began, has struggled mightily to manufacture its product with a consistency that would satisfy the FDA.

In fact, some efficacy data the company generated on its vaccine weren’t presented to the committee because it was made using a slightly different process than is being currently deployed by the Serum Institute of India, which is making Novavax’s product now. The company said it had shown that the vaccines were comparable, but the FDA did not agree, with Doran Fink, acting deputy director of the office for vaccines research and review, saying the agency believes there are “important differences” in the lots of vaccine used in some of the clinical trials the company conducted. As a consequence of the FDA’s decision, only safety data were presented from the affected trials.

“What you’re seeing is the product you’re getting,” Peter Marks, director of the Center for Biologics Evaluation and Research, said of the data that was presented to VRBPAC.

The one abstention in the vote was from Bruce Gellin, former head of national vaccine program office in the Department of Health and Human Services and now chief of global public health strategy at the Rockefeller Foundation, who made clear his vote should not be seen as a vote against the vaccine. He called Novavax’s efforts to get to this point “a case study in perseverance.”

Gellin explained after the fact that he would have liked to vote a provisional yes, but that wasn’t an option. The data Novavax presented showed its vaccine was safe and effective but they were conducted when the Alpha and Delta variants were circulating, he said. The committee wasn’t shown data to suggest whether the two-dose vaccine would be as effective today, in the era of Omicron; Gellin said it will be important to evaluate the product going forward if it is authorized.

The company’s chief scientific officer, Filip Dubrovsky, argued that the way the vaccine is made — using a boosting compound known as an adjuvant — leads the company to believe that its vaccine will offer broader cross-protection against different variants of the SARS-CoV-2 virus.

Likewise Novavax and the FDA disagreed on some safety data. Five cases of myocarditis — inflammation of the heart muscle — were seen among people who have received the vaccine in the clinical trials Novavax conducted. While one of the individuals had strep throat, which might have explained the myocarditis, the FDA concluded that a causal association with the vaccine couldn’t be ruled out in these cases. It has asked the company to list a risk of myocarditis on the vaccine’s product insert. The company, though, believes a causal association has not been shown.

Myocarditis and pericarditis — inflammation of the muscle around the heart — have been seen following vaccination with the mRNA vaccines produced by Moderna and by the partnership of Pfizer and BioNTech.

The Novavax vaccine is a two-dose vaccine, with the doses given 21 days apart. While both the Pfizer and Moderna vaccines are also licensed as two-dose products, the reality is two doses do not provide adequate protection against the Omicron variant and the FDA and the Centers for Disease Control and Prevention have recommended a booster shot for everyone who received those vaccines. A fourth dose — characterized as a second booster — has been authorized for older adults.

Novavax’s Dubrovsky said the company has generated data on the impact of booster shots and will apply to the FDA for authorization for boosters down the road. It has also tested the vaccine in adolescents aged 12 to 17 and will be applying for an expansion of the EUA to included that age group if and when the vaccine receives an EUA.