https://www.bioworld.com/articles/520241-novavax-vaccine-shows-its-chops?v=previewNovavax vaccine shows its chops
Given that Novavax Inc.'s COVID-19 vaccine will be a latecomer to the U.S. scene if it gets FDA authorization, it's been cast in a supporting role to the lead being played by the mRNA vaccines from Moderna Inc. and Pfizer Inc.-Biontech SE.
But the data presented at the June 28 Vaccines and Related Biologic Products Advisory Committee (VRBPAC) meeting suggest the Novavax adjuvanted protein vaccine may have the chops to take on a larger role in taming the pandemic.
"The Novavax data was pretty significant in that the ancestral strain in their formulation was able to give pretty good protection against omicron 5," said VRBPAC panelist Wayne Marasco, a professor at the Dana-Farber Cancer Institute and Harvard Medical School.
At the same time, "we may be witnessing some limitations with the mRNA vaccines," he said. "Yes, they were the first ones out of the gate, but they don't appear to be able to have that kind of breadth of protection."
Marasco wasn't the only one impressed with the Novavax data. "The most compelling thing that I've seen today is the data from Novavax" showing protection against BA.1, BA.2 and BA.5, said James Hildreth, president and CEO of Meharry Medical College. "It might be timely for the agency to quickly review the data" and approve the Novavax vaccine, he added. As an additional selling point for the Novavax vaccine, Hildreth noted that many people who have shied away from the mRNA vaccines might be more comfortable with the protein vaccine.
Novavax submitted a request to the FDA in January for an emergency use authorization (EUA) for its vaccine. Earlier this month, the vaccine won unanimous VRBPAC support. Although the FDA has acted within one day of similar VRBPAC meetings to grant or expand EUAs for COVID-19 vaccines, it has yet to act on the Novavax vaccine. Speaking at the June 28 meeting, Peter Marks, director of the FDA's Center for Biologics Evaluation and Research, said he couldn't say when the agency would make its decision, citing confidentiality.
Amid the VRBPAC enthusiasm for the Novavax vaccine, the FDA's Jerry Weir cautioned that the agency had yet to review the new data presented about the company's vaccine and boosters. In addition to reviewing the efficacy data for its primary vaccine, the Gaithersburg, Md.-based company discussed preclinical data on the boosters it has in development, including the prototype vaccine, an omicron BA.1 monovalent vaccine and a bivalent product containing BA.1.
All the boosters, given eight months after the primary series (instead of the five months for the Moderna and Pfizer shots), generated antibody levels consistent with those seen in the original phase III vaccine trials conducted in the U.K. and the U.S./Mexico, according to the company.
In those trials, the Novavax vaccine showed a 90% efficacy against any COVID-19 infection and 100% efficacy against severe disease. In the U.S./Mexico trial, it showed 93% efficacy against all the variants of interest or of concern circulating at the time. In the U.K. trial, the efficacy against the variants was 86%.
"We are confident that our prototype COVID-19 vaccine generates broad levels of antibodies as a primary series, and that boosting with this prototype vaccine increases the magnitude of the breadth of response," Gregory Glenn, president of R&D at Novavax, said following the VRBPAC meeting. "While we believe in the strength of our prototype vaccine data, we are prepared to supply an omicron-based vaccine this fall in accordance with health authority recommendations."
Global concerns
In addition to the Novavax EUA, the FDA has a lot to consider when it comes to preparing for the next scene of the pandemic. While the VRBPAC supported the inclusion of an omicron component in future boosters, FDA officials will have to decide what that component should be, how it should be used and whether the data should be extrapolated for all age groups. A few VRBPAC members also encouraged the agency to be cognizant of the impact its decisions may have on other countries, especially since the decisions will involve global manufacturers.
The World Health Organization's Technical Advisory Group on COVID-19 Vaccine Composition addressed that issue in its most recent guidance. While the advisory group is recommending boosters with an omicron component, it said the recommendation doesn't preclude the consideration of other variant-specific formulations by regulators. Given the way the virus is evolving in different countries, the needs could differ.
To date, the vaccines in use globally are based on the original Wuhan strain. VRBPAC panelist Bruce Gellin, chief of global public health strategy at the Rockefeller Foundation, asked what would happen to the global vaccine supply if the U.S. were to require a composition change.
"I don't have an answer for that," the FDA's Weir responded, adding that the concern factored into WHO's recommendation to maintain the current primary vaccine based on the ancestral strain.
These are global manufacturers, Gellin said, so the FDA has to consider the ramifications of having a different booster and what's available elsewhere in the world.
In his closing remarks, Weir said he heard the committee's concerns about the importance of global coordination. The FDA will consider that and work on it going forward, he said.
