Novavax Inc. (NVAX  ) stock is trading lower on Wednesday. The FDA has placed a clinical hold on Novavax's Investigational New Drug (IND) application for its COVID-19-influenza combination (CIC) and stand-alone influenza vaccine candidates.

The clinical hold is due to a spontaneous report of a serious adverse event (SAE) of motor neuropathy in a single CIC Phase 2 trial participant outside the U.S. who received the vaccine in January 2023.

Motor neuropathy is a condition that occurs when the nerves that control movement are damaged.

The trial was completed in July 2023, and the participant reported the SAE in September 2024.

"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 Robert Walker, Chief Medical Officer, Novavax.

Data from Novavax's previous COVID-19 and influenza trials have shown no signals for motor neuropathy. Investigators have been informed of this action.

The clinical hold does not impact the COVID-19 IND for Novavax's COVID-19 vaccine. In April 2022, Novavax announced initial results from the Phase 1/2 trial of its CIC Vaccine.

The preliminary trial results found that various CIC vaccine formulations induced immune responses in participants comparable to reference stand-alone influenza and stand-alone COVID-19 vaccine formulations.

The company said that the combination vaccine was found to be generally well-tolerated. Serious adverse were rare, and none were assessed as related to the vaccine.

Last week, the European Commission approved Novavax's updated 2024-2025 Nuvaxovid COVID-19 Vaccine (recombinant, adjuvanted) (NVX-CoV2705), dispersion for injection, for use in individuals aged 12 and older to prevent COVID-19 in the European Union.

Price Action: NVAX stock is down 19.10% to $10.20 during the premarket session at last check on Wednesday.