The FDA and CDC greenlit Novavax's (NVAX) original COVID-19 vaccine for use as a booster in some adults, marking the first monovalent vaccine to receive authorization as a booster against the latest Omicron variants.
The authorization specifies that adults who have not yet received a bivalent booster but have completed their primary vaccine series can received the Novavax dose at least six months after their last shot.
That includes if their primary doses were mRNA and if an mRNA bivalent booster is not available or clinically appropriate, according to the FDA.
Novavax chief commercial officer John Trizzino told Yahoo Finance that the company is already working on clinical trial data that it hopes will amend the emergency use authorization (EUA) to include the option for use as a second booster.
"The data that we submitted was exclusively for the first boost dose. Now, logically, you would think that if you're good enough to be the first heterologous boost then you should be good enough to do a second heterologous boost ... but they wanted to see additional data," Trizzino said of the FDA.
He said he doesn't have a timeline for when that second boost data will be available, however.
About 20% of the adult population has yet to receive any vaccine for COVID and at least 50% have not received a booster, Trizzino said.
While mRNA doses have been available for second boosters since September, uptake has been slow.
As of last week, about 5% of the eligible population has received an additional booster. Older adults are doing better, with about 40% of adults over the age of 50 and 46% of adults over 65 having received their second doses, according to the CDC.
That's where Novavax sees market opportunity, according to Trizzino.
"There's still significant opportunity there for those people that want to get another vaccine," he said.
By comparison, mRNA second boosters were required to be bivalent shots with against the BA.4/BA.5 Omicron subvariants, which were the dominant strains in the summer.
At a meeting in June, the FDA determined that the vaccine companies, including Moderna (MRNA) and Pfizer/BioNTech (PFE/BNTX), needed to reformulate in order to provide the best possible protection. Both mRNA vaccines have since been authorized as second boosters, and the original formulas are no longer allowed to be used for boosters, the FDA said. And the companies have only just released data about the efficacy of the new shots — which were approved without clinical data.
Those boosters have no limitations because the potential for a mix and match with a primary Novavax recipient is low.
"We're being held to a different and higher standard," Trizzino said.
But that doesn't mean Novavax's vaccine will not be used as a second booster.
"What a health care provider chooses to do is up to a health care provider," Trizzino said.
Stock under pressure
Despite the news, the company's stock remained under pressure Wednesday.
It has been down from the highs of 2021, as firms like JPMorgan have expressed doubt about the company's future.
That's something Trizzino said the company is acutely aware of.
"I think that the doubts are in overall kind of market size —What does the investment community think about the what the COVID market will be going forward? Will it continue to shrink aggressively? Will people get vaccinated? There's a variety of opinions about what the global Covid market will be," he said.
Novavax isn't the first COVID vaccine company to see a split between regulatory news and stock movement. Pfizer's CEO had been similarly frustrated by the investment community's reaction to its vaccine even after record sales.
Trizzino said the difference is that now people are more complacent about the virus, and another surge — like the one experts are anxious about striking this winter — could trigger more vaccinations.
"I think the investment community, as far as Novavax is concerned, wants to see what the rest of the year looks like. I think there's some doubt ... about what the total global COVID marketplace looks like into the future," Trizzino said.
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