Novavax’s COVID-19-Influenza Combination vaccine faces a clinical hold after a trial participant developed motor neuropathy, pending further investigation by the FDA. The FDA has placed a clinical hold on the investigational new drug (IND) application for Novavax’s COVID-19-Influenza Combination (CIC) and stand-alone influenza vaccines because of a severe adverse event (AE) of motor neuropathy reported to occur in a trial participant of the ongoing phase 2 trial of the CIC vaccine, which completed in July 2023.1 This patient was at a site outside of the US and received the vaccine in January 2023—the serious AE was reported in September 2024.