The Biden administration is warning states to prepare for a "limited supply" of Novavax's COVID-19 vaccine to be made available after federal health authorities cleared the shots for use on Tuesday. States will likely be unable to begin requesting their first shipments until next week.
"A limited number of doses of Novavax COVID-19 vaccine will be distributed and not all providers are expected to carry Novavax COVID-19 vaccine," says a planning document published this week by the Centers for Disease Control and Prevention.
States will not be able to begin ordering from the Biden administration's supply of Novavax's vaccine until the week of July 25, the document "tentatively" estimates.
That could mean the first shots of Novavax's vaccine will not arrive in doctors' offices and pharmacies until August – a timeline previously floated by health authorities.
Spokespeople for the Department of Health and Human Services did not respond to multiple requests for comment.
Why is there a delay in rolling out the vaccines?
The federal approach to rolling out Novavax's vaccine marks a departure from the high-profile campaigns to quickly deploy previous brands, like Pfizer-BioNTech or Moderna. Those shots saw shipments begin within days after they were first authorized.
At least part of the delay in supplying Novavax's doses appears to be the result of quality testing still ongoing to clear the company's shots, which is only now wrapping up.
Novavax said in a statement that the Food and Drug Administration had recently signed off on the quality of its first vaccine lot, clearing it for release.
"Novavax expects to ship doses to the U.S. Government-designated distribution center in the coming days," the company said.
How much of the vaccine will be available, and who will be able to get it?
Approximately three million doses of Novavax's vaccine will be made available for health departments to request in total. The Biden administration has urged states to direct doses from their "one-time" allocation "to providers with expected demand among unvaccinated patients."
Around 1 in 10 American adults have yet to get at least one COVID-19 vaccine dose, according to the CDC's figures, or at least 26 million adults. Around 16% of those unvaccinated adults told a CDC survey that they "probably" or "definitely" will get vaccinated if a protein-based vaccine like Novavax was available.
The document also says states should try to plan for redistributing the shots in ways that minimizes wastage of the limited stocks of Novavax's vaccine, which come in 10-dose vials that must be used within 6 hours after opening.
But like with other shots, the CDC also emphasizes that doctors "should not miss any opportunities to vaccinate every eligible person" who requests a shot, even if it ends up wasting several other doses in the vial.
"We are working feverishly to get a lower format of presentations that we can submit to the regulators and get approval in due course," Novavax's Filip Dubovsky said at a meeting of the CDC's advisers on Tuesday.
Where will I be able to get it?
It's unclear how those initial batches of Novavax's vaccine will be divided up by the Biden administration between states and other federal vaccination channels like drug stores or health centers.
For example, the CDC says its federal retail pharmacy program had administered more than 250 million doses in the COVID-19 vaccination campaign through early July. But a spokesperson for at least one of the program's participants, CVS, said their drug stores have "no immediate plans to offer the Novavax vaccine at our retail locations."
"The Moderna and Pfizer COVID-19 vaccines remain readily available for patients," said CVS spokesperson Matt Blanchette.
What was the reason for the previous delays?
This timeline is the latest delay for Novavax's vaccine reaching unvaccinated adults, now more than six weeks after the company's shots won the near-unanimous backing of the FDA's outside vaccine advisers on June 7.
The FDA did not grant emergency authorization for the company's shots until July 13.
Documents published by the FDA this week reveal that during that time, talks with the regulator yielded changes to how Novavax described the risk of allergic reactions and a rare heart inflammation side effect known as myocarditis or pericarditis.
The company went from calling them "important potential risks" to "important identified risks" linked to their vaccine.
The documents also say that Novavax told the regulator "during the late stage" of its review that it had made tweaks to how its vaccine was being manufactured. Testing later showed that those changes did not appear to impact the purity or quality of the shots.
In a statement after the shots were authorized, the FDA's Dr. Peter Marks said the agency's "comprehensive analysis and evaluation" had concluded that Novavax's vaccine "meets the FDA's high standards for safety and effectiveness for emergency use authorization."
"The American public can trust that this vaccine, like all vaccines that are used in the United States, has undergone the FDA's rigorous and comprehensive scientific and regulatory review," said Marks.
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