Novavax has announced that the U.S. Food and Drug Administration (FDA) has lifted the clinical hold on its Phase 3 study evaluating the company's COVID-19/influenza combination vaccine and its stand-alone influenza vaccine candidates. This decision allows Novavax to proceed with the late-stage trial, marking a significant step forward in the development of these vaccines.
The clinical hold was initially placed in October following a spontaneous report of a serious adverse event, initially characterized as motor neuropathy, in a participant who had received the investigational combination vaccine during a Phase 2 trial completed in 2023. Subsequent information provided to the FDA revised the diagnosis to amyotrophic lateral sclerosis (ALS), a condition not typically associated with immune-mediated responses or vaccination.
According to Novavax, the FDA has determined that the company adequately addressed all concerns related to the clinical hold. This determination enables Novavax to begin enrolling participants in the planned Phase 3 trial. The company is now working with clinical trial investigators and partners to resume trial activities as quickly as possible.
"We thank the FDA for its partnership and thorough review of the additional information provided as part of our response package," said Robert Walker, Novavax’s chief medical officer. "The information provided to the FDA supported our assessment that the serious adverse event was not related to our vaccine. We plan to start our phase 3 trial as soon as possible."
Novavax's vaccines incorporate its Matrix-M adjuvant, designed to enhance the immune system's recognition of vaccine components and prolong immune memory, potentially extending the duration of protection offered by the vaccine.
The lifting of the clinical hold occurs less than three months after the FDA granted emergency use authorization (EUA) to Novavax’s JN.1-adapted COVID-19 vaccine for individuals aged 12 years and older. The EUA was supported by non-clinical data demonstrating cross-reactivity against the JN.1 variant and multiple JN.1 lineage viruses, including KP.2.3, KP.3, KP.3.1.1, and LB.1.
Sanofi Collaboration
Novavax also recently entered into a licensing agreement with Sanofi, valued at over $1.2 billion, to co-commercialize its COVID-19 vaccine and develop combination vaccines for COVID-19 and influenza. This agreement grants Sanofi a co-exclusive license to co-commercialize Novavax’s current stand-alone adjuvanted COVID-19 vaccine globally, excluding countries where Novavax has existing partnership agreements, such as Japan, India, and South Korea, as well as those with advance purchase agreements.
