Editor's note: The headline of this article has been updated to reflect that two vaccine programs are affected by the clinical hold.
Novavax’s plans for growth outside of its COVID program have been thrown into chaos after the FDA put two of the biopharma's programs on hold in response to a case of nerve disease from a former participant in a trial of the biotech’s COVID-influenza combination vaccine.
The patient had received the COVID-flu shot back in January 2023, with the phase 2 trial wrapping up six months later, Novavax explained in a Securities and Exchange Commission filing. The report of a patient outside the U.S. who had developed motor neuropathy—a disease of the nerves that control muscles—was not received until last month, the company said.
As a result, the FDA has put the brakes on Novavax’s plans to launch a phase 3 trial of both the combo shot and a standalone flu vaccine later this year.
The company’s shares were rocked by the news, trading down 19% at $10.20 in premarket trading Wednesday from a Tuesday closing price of $12.60.
“We are working closely with the FDA to provide the necessary information that will allow them to better understand this observation and resolve the clinical hold,” Novavax's Chief Medical Officer Robert Walker, M.D., said in a statement. “While we do not believe causality has been established for this serious adverse event, we are committed to working expeditiously to fulfill requests for more information from the FDA. Our goal is to successfully resolve this matter and to start our phase 3 trial as soon as possible.”
It comes at a tricky time for Novavax, with CEO John Jacobs promising in August that the company would “unveil a new and expanded clinical pipeline by the end of this year.” Ahead of this, the biotech had already offloaded half of the commercialization duties for its European Medicines Agency-approved COVID-19 subunit vaccine Nuvaxovid to Sanofi in exchange for $500 million upfront.
That deal saw Novavax retain the rights to its combo COVID-flu vaccine, while Sanofi has the sole license to use Novavax’s adjuvanted COVID-19 vaccine in combination with Sanofi's own flu vaccines.
The biotech entered 2024 overseeing the second round of layoffs in less than a year, with the company’s headcount reduced by about 30% across the two events. It followed news that Novavax was aiming to bring general expenses and R&D costs below $750 million in 2024, a greater than 50% reduction from 2022 levels.
The company’s plans to boost the value of the business are grounded “not only [in] the Sanofi partnership but also through our late-stage combination and influenza assets,” Jacobs said back in August.
Both the combo shot and the standalone flu vaccine held their own in last year’s phase 2 trial. The combo in particular achieved similar anti-S IgG antibody responses to Novavax’s phase 3 protein recombinant COVID-19 vaccine, as well as hemagglutination inhibition (HAI) antibody responses in line with Seqirus’ approved flu shot Fluad or Sanofi’s Fluzone High Dose.
The company said at the time that there were “no adverse events (AE) of special interest” during the trial.