A  rollout of the protein-based vaccine may not be speedy, however, due to a number of uncertainties related to both safety and manufacturing.  Beyond the Maryland-based biotech’s own production problems that caused it to delay filing with the FDA over several months last year, the health watchdog has raised concerns about the risk of myocarditis.

During Novavax's clinical trial with nearly 30,000 participants between December 2020 and September 2022, the inflammatory hear condition was diagnosed in four people within 20 days of vaccination. The FDA has asked Novavax to list myocarditis, as well as another type of heart inflammation, pericarditis, in its packaging information, but according to reports the company has not yet agreed.

Despite voting to approve the authorization, some of the independent health experts reviewing the Novavax trial data noted that some of it is out of date as Nuaxovid has been not tested against the omicron Covid variant or any of its subvariants. In the pre-omicron trials, the vaccine was shown to be 90% effective.

Along with Novavax itself, some close to the approval process have touted the vaccine as a booster. The same has been said for the shots being developed by latecomers CureVac and GSK.

Some question the need for another vaccine, with three effective shots already on the US market, but Peter Marks, director of the FDA’s Center for Biologics Evaluation and Research, has said he believes a vaccine based on conventional technology might encourage people fearful of the mRNA shots to roll up their sleeves. In Europe, where Nuaxovid has been administered for several months, this has hardly been the case, however.

Marks has argued also that the Janssen vaccine is currently not being used as a frontline vaccine, so  that effectively there are only the two mRNA shots. Because of the risk of a rare and dangerous clotting condition, the FDA last month limited the emergency use authorization of Janssen shot to adults who can’t or won’t have another type of vaccine.

“We do have a problem with vaccine uptake that is very serious in the US, and anything we can do to make people more comfortable to accept these potentially lifesaving products is something we are compelled to do,” the FDA official said.

According to the Centers for Disease Control and Prevention (CDC), 48.7% of US residents over the age of 12 have received three doses. The heath agency said this is a lower than in other countries with similar access to vaccines, including the UK (nearly 70% boosted), Canada (55.5%) and the EU (62.6%).

The CDC’S figures also show that 27 million adults in the US have not received even one dose.

Author: Dede Williams, Freelance Journalist