FDA places hold on Novavax’s COVID-influenza combo vaccine

The FDA has placed a hold on the investigational new drug (IND) application for Novavax’s COVID-19 and influenza combination vaccine candidate, as well as a standalone influenza vaccine candidate. The hold does not affect the standalone COVID-19 vaccine.

The FDA’s decision follows a report of a serious adverse event from a patient outside the US who took part in a phase 2 trial with the combination vaccine that had been completed in July 2023.

The participant, who received the vaccine in January 2023, reported developing a case of motor neuropathy in September this year. This report led the FDA to halt the development of the vaccine to investigate whether the adverse event could be related to the vaccine candidate.

Robert Walker, Chief Scientific Officer of Novavax, stated that the company has no reason to believe this adverse event was caused by the vaccine. No other cases of motor neuropathy have been reported in previous clinical trials evaluating the combination COVID-19 and influenza vaccine.

"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," said Walker. "It is important to note that safety is our top priority, and 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."

The results of the completed phase 2 trial with both the combination and standalone influenza vaccine were positive. For the influenza vaccine candidate, the response was significantly higher than that of Novartis’ Fluad and Sanofi’s Fluzone, two commercially available influenza vaccines

Novavax had plans to launch a phase 3 trial of both the combination and standalone influenza vaccine later this year, which may be affected by the clinical hold placed by the FDA.

The news comes as the company executes a strategy to reduce annual expenses and R&D costs by more than 50% — including two layoffs that reduced its workforce by approximately 30%​ at the beginning of this year.