A Novavax Covid-19 vaccine developed for the fall vaccination season now has the FDA green light, bringing an alternative to the messenger RNA shots that are already rolling out to pharmacies, doctor’s offices, and other locations throughout the country.
The FDA decision announced Tuesday afternoon is not an approval. Last year’s emergency authorization for the Novavax vaccine is now amended to include an updated formula, which reflects currently circulating variants. The initial Novavax vaccine was authorized for those 18 and older. For the updated shot, the FDA expanded the age range to 12 and older. The regulatory decision for the latest version of the Novavax vaccine means the company’s initial vaccine, developed for the original SARS-CoV-2 strain, is no longer authorized for use in the U.S.
Gaithersburg, Maryland-based Novavax makes its protein-based vaccines with nanoparticle technology that engineers proteins that mimic antigens found on natural pathogens. For its Covid-19 vaccine, the technology yields a version of the spike protein from SARS-CoV-2. The updated formula is designed to prompt an immune response to XBB.1.5, the same omicron variant addressed by the updated messenger RNA vaccines. This target was recommended in June by an FDA advisory committee and is consistent with guidance from the European Medicines Agency and the World Health Organization.
Since June, different strains emerged. Over the summer, Novavax and the mRNA Covid-19 vaccine makers each reported data showing their respective vaccines produced antibody responses to newer variants accounting for most of the cases in the U.S. and Europe. Novavax said the amended emergency authorization is based on non-clinical data showing its shot induced immune responses against XBB.1.5, XBB.1.16, and XBB.2.3. The company also said additional data showed its vaccine induced neutralizing antibody responses to newly emerging subvariants and robust T cell responses against EG.5.1 and XBB.1.16.6, suggesting a broad response that stimulates both arms of the immune system.
Novavax’s vaccine comes with an adjuvant, an ingredient that boosts the immune response. Inclusion of the adjuvant means it takes a lower dose to achieve the desired immune response. Stretching those doses in turn extends Novavax’s vaccine manufacturing capacity.
According to the FDA authorization for the Novavax vaccine, those previously vaccinated with any Covid-19 shot may receive the updated vaccine as a single shot, as long as it comes at least two months after a person’s last coronavirus vaccination. For those who have not received any Covid-19 vaccine, the FDA said dosing of the Novavax vaccine is two shots, given three weeks apart. Immunization of immunocompromised people is a single dose administered at least two months after the last Covid-19 vaccine shot. Additional doses and the timing of those doses may be given at the discretion of a patient’s healthcare provider.
The FDA last month approved the updated mRNA Covid-19 vaccines from Moderna and partners Pfizer and BioNTech. The Centers for Disease Control and Prevention subsequently recommended that everyone age 6 and older receive an updated Covid-19 vaccine. That recommendation now encompasses Novavax’s vaccine, except for those younger than 12 who are not eligible under the amended authorization.
“Novavax’s authorization today means people will now have the choice of a protein-based non-MRNA option to help protect themselves against Covid-19, which is now the fourth leading cause of death in the U.S.,” Novavax CEO John Jacobs said in a prepared statement. “In the coming days, individuals in the U.S. can go to pharmacies, physicians’ offices, clinics and various government entities to receive an updated Novavax vaccine.”
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