FDA Halts Novavax Trial of Combo COVID-Flu Vaccine Citing Patient With Nerve Damage

The FDA halted Novavax’s trial of its experimental COVID-19-flu combination vaccine and its standalone flu shot after a trial participant reported nerve damage, the company said today.

by Brenda Baletti, Ph.D.

The U.S. Food and Drug Administration (FDA) halted Novavax’s trial of its experimental COVID-19-flu combination vaccine and its standalone flu shot after a trial participant reported nerve damage, the company said today.

The patient received the COVID-flu shot in January 2023 during Phase 2 trials for the drug. However, Novavax said it didn’t receive the report showing the participant had developed motor neuropathy — a disease affecting the nerves that control muscles — until last month.

In response, the FDA put a clinical hold on Novavax’s COVID-flu Phase 3 trial, which was set to begin this month, and on its flu vaccine trials. The company finished its Phase 2 trial last year.

In a press release, Novavax said the data from previous COVID-19 and flu trials showed no safety signals for motor neuropathy.

The company said it did not believe there was sufficient evidence to show the neuropathy was causally linked to its 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,” Novavax’s Chief Medical Officer Robert Walker said.

Novavax’s share price immediately plummeted about 20% in early trading. The company is struggling financially, FierceBiotech reported, having begun 2024 with a second round of layoffs that reduced its workforce by around 30%. Its growth plans are largely based on these two vaccines.

Patients in other recent drug trials injured, but FDA approved drugs anyway

Novavax’s only commercial product is its protein-based COVID-19 vaccine, which has failed to garner a significant market share relative to the Pfizer and Moderna mRNA vaccines, Reuters reported.

As of Aug. 17, 2022, only 11,990 doses of the Novavax COVID-19 vaccine had been administered in the U.S. And between July 13, 2022, and March 13, 2023, only 69,227 Novavax doses were administered.

There have been 545 adverse events reported to the Vaccine Adverse Event Reporting System (VAERS) associated with the Novavax COVID-19 vaccine. They include serious adverse events such as Guillan-Barré syndrome — a rare disorder in which the body’s immune system attacks its nerves — thrombosis, pericarditis and seizures.

Dr. Meryl Nass, an internist, told The Defender there have been other recent drug trials in which participants suffered serious adverse events similar to the one reported by Novavax today — yet the trials were allowed to continue, and the drugs were approved.

For example, in the adult RSV trials for Pfizer’s Abrysvo, two participants were diagnosed with Guillain-Barré syndrome. In GSK’s Arexvy vaccine trial, there was one reported case of Guillain-Barré and one death, both of which the FDA found to be potentially linked to the vaccine.

In May 2023, the FDA approved Abrysvo for adults over 60, and in June 2023, the agency approved Arexvy for the same population.

The Centers for Disease Control and Prevention narrowed the recommended age group for the drug to adults over 75 in June 2024, citing growing evidence of adverse events associated with the RSV vaccine. Consistent with evidence from clinical trials, those adverse events included the documented risk of Guillain-Barré syndrome.

“Although I’m glad the trial was suspended, I strongly believe the FDA should explain why some trials are given a pass for serious adverse events, including death, and others are not,” Brian Hooker, Ph.D., chief scientist for Children’s Health Defense, told The Defender.

He added:

“With industry money flowing freely at FDA through programs like Fast Track, this type of move is not surprising. Unfortunately, it puts the patient-consumers in the direct line-of-fire of faulty products that are inappropriately approved based on corporate pressure and not safety.”