Novavax’s Covid-19 vaccine wins backing of CDC advisory panel

An expert panel that advises the Centers for Disease Control and Prevention on vaccine policy voted Tuesday to recommend use of Novavax’s Covid-19 vaccine — an achievement a long time in the making for the Gaithersburg, Md.-based company.

The Advisory Committee on Immunization Practices voted 12-to-0 to recommend the vaccine, with several members expressing hope that the vaccine’s makeup may persuade some people who have been reluctant to get vaccinated against Covid to finally roll up a sleeve. The vaccine is a recombinant protein product, developed with the same kind of approach that has been used for a number of vaccines over the years. Some people who have refused Covid vaccines have expressed hesitancy over the messenger RNA vaccines produced by Moderna and the Pfizer and BioNTech partnership.

CDC Director Rochelle Walensky accepted ACIP’s recommendation within hours of the vote. In a statement, she said the Novavax vaccine will be available “in the coming weeks.”

“Today, we have expanded the options available to adults in the U.S. by recommending another safe and effective Covid-19 vaccine,” she said. “If you have been waiting for a Covid-19 vaccine built on a different technology than those previously available, now is the time to join the millions of Americans who have been vaccinated. With Covid-19 cases on the rise again across parts of the country, vaccination is critical to help protect against the complications of severe COVID-19 disease.”

The Novavax vaccine will be the fourth Covid vaccine to be authorized in the United States, following vaccines developed by Pfizer, Moderna, and Johnson & Johnson. The latter vaccine is only recommended for people who cannot take one of the other options, because of a rare but serious side effect.

“We think vaccine choice is important, particularly as we expect to see ongoing surges of COVID-19 and work to increase vaccination rates,” said Stanley C. Erck, Novavax president and chief executive officer, said in a statement. “With demonstrated efficacy and a reassuring safety profile, our vaccine is the country’s first protein-based option.”

This is the first product Novavax has brought to market. The vaccine showed impressive efficacy when it was tested in Phase 3 clinical trials, results that almost rivaled the mRNA vaccines.

But those trials were done last year, when the Alpha variant was the predominant strain of the SARS-CoV-2 virus in circulation.

There are no efficacy data available with which to gauge how well the vaccine has held up against the Omicron variant, which is so different from earlier versions of the virus that it has eroded the efficacy of other Covid vaccines. Immunogenicity data — looking at antibody levels in people vaccinated — suggest the vaccine has lower but still important effectiveness against Omicron variants.

Novavax’s chief medical officer, Filip Dubrovsky, said the company is testing a new version of the vaccine, which includes an Omicron strain. If it works, the company hopes to have supplies in the fourth quarter of this year, he told the ACIP.

The vaccine has already been authorized by a number of other countries, though only 1 million doses had been used worldwide by the end of June, according to slides presented by Dubrovsky. The U.S. government recently announced it has secured 3.2 million doses of the Novavax vaccine.

Initially the vaccine will only be authorized for use in people 18 and older. The vaccine is given in two doses, which ideally are given three weeks apart. But CDC staff advising the ACIP noted that health care providers who are concerned about the possibility of myocarditis in recipients of the vaccine — the risk is highest among males in their teens and early 20s — could delay giving the second dose to lower that risk. If the second dose is delayed, it should be given within eight weeks of the first dose.

The problem of myocarditis and pericarditis — inflammation of the heart and tissue around the heart, respectively — was first seen with the mRNA vaccines. It is also a rare but real side effect of the Novavax vaccine.

“I was kind of disappointed about the myocarditis data,” said ACIP member Pablo Sanchez, a professor pediatrics at the Ohio State University, saying more research needs to be done to determine why Covid vaccines trigger the condition in some people.

The authorization at this point is only for use of the vaccine as a primary series; it cannot be given as a booster for other brands of vaccine. Likewise, there currently isn’t an authorization for additional booster doses for people who get the Novavax vaccine — though the CDC staff told the committee it is expected they will be needed.

The vaccine has some characteristics that would have given it an advantage against the mRNA vaccines, if the company had been able to bring it through the approval process sooner. It does not require the ultra-cold temperatures needed to store the Pfizer and Moderna vaccines; it can be stored at fridge temperature.

But because of its lateness to the market, it now faces a disadvantage. The vaccine is sold in 10-dose vials and vials must be discarded six hours after the first dose is withdrawn. Given the numbers of Americans who still haven’t had a primary vaccination series at this point, there could be substantial wastage.

The company announced Tuesday that it will produce its Omicron-containing vaccine in single-dose, pre-filled syringes.