The U.S. Food and Drug Administration (FDA) has put a hold on Novavax’s COVID-influenza combination vaccine and standalone influenza vaccines being tested in clinical trials after a participant reported nerve damage following receipt of the experimental vaccine in January 2024.1
Reported symptoms were diagnosed as motor neuropathy, a disease process that can be acquired, hereditary or immune mediated that damages nerve fibers, leading to muscle weakness and atrophy. The disease is not usually life-threatening but often progresses and can become debilitating.2
According to Novavax officials, a direct link between the shot and neuropathy has not yet been established, but stated that the company is working closely with the FDA to lift the pause so trials can resume. “Our goal is to successfully resolve this matter and to start our Phase 3 trial as soon as possible,” said Novavax’s chief medical officer, Robert Walker, MD.1
The pharmaceutical company’s shares plunged 24 percent following news of the FDA’s action. Reportedly, if the decline continues, it could erase almost $400 million from the Novavax’s market value. The drop in shares could jeopardize Novavax’s partnership with French drug maker Sanofi, according to one analyst. In May 2024, Sanofi announced the partnership with Novavax to develop and commercialize a global COVID-influenza combination vaccine.3
According to a press release, Novavax would receive up to $1.2 billion from Sanofi, including an upfront payment of $500 million. Another issue for investors is the low demand for Novavax’s COVID-19 vaccine, its only approved product, due to its delayed launch in the U.S. market.3
Novavax’s protein-based COVID vaccine was designed as an alternative for patients who wanted to avoid mRNA COVID shots manufactured by Pfizer/BioNTech and Moderna, which have raised concerns about reported heart complications and other side effects, as well as the potential long-term negative impact on health associated with the new mRNA technology. The clinical hold on its vaccine trial is a significant blow to Novavax, which is trying to launch new products as global demand for its COVID vaccine declines.1
This Year’s Flu Shot Effectiveness “Disappointing”
The news of Novavax’s halted clinical trial for their combination influenza-COVID vaccine follows “disappointing” data on this year’s flu shot effectiveness. New data indicates that this year’s influenza vaccine is less effective, reducing the risk of hospitalization by only 34.5 percent, compared to the more typical estimated 50 percent effectiveness rate. This finding comes from a study conducted in five South American countries—Argentina, Brazil, Chile, Paraguay, and Uruguay—during their flu season from March to July of this year.4
According to the U.S. Centers for Disease Control and Prevention (CDC), influenza vaccination rates among Americans have declined post-pandemic, particularly among white children and seniors over 65. It appears health care professionals are not exempt from this trend. Nebraska Medicine, a prominent academic health network, reported this week that influenza and COVID vaccination rates among its staff are significantly below their targets. As of Oct. 21, 2024, influenza vaccination rates in the health network are 30.7 percent and 28.9 percent, while uptake of COVID shots is just 9.5 percent. The organization has set a goal of 90 percent flu vaccine compliance and 100 percent documentation.5 6
The CDC’s recent report highlights further concerns with declining vaccination rates among healthcare personnel. Only 75.4 percent of health care workers received a flu shot for the 2023-2024 season, with even lower coverage in long-term care settings (65.2 percent). COVID vaccination rates are also very low, with just 31.3 percent of health care personnel receiving the updated shots.7
If you would like to receive an e-mail notice of the most recent articles published in The Vaccine Reaction each week, click here.
Click here to view References:1 Satija B. US FDA pauses Novavax’s trial of combo COVID-flu shot on safety concerns. Reuters Oct. 16, 2024.
2 Verschueren A. Motor neuopathies and lower motorneuron syndromes. Revue Neurologique 2017; 173(5): 320-325.
3 Press Release. Sanofi and Regeneron announce positive results in Phase 3 trial for Dupixent in COPD Sanofi May 10, 2024.
4 Rodriguez A. How effective is the flu shot this year? New report reveals ‘disappointing’ data. USA Today Oct. 4, 2024.
5 U.S. Centers for Disease Control and Prevention. Flu vaccination coverage, United States, 2023-2024 season. 2024.
6 University of Nebraska Medical Center. Colleague vaccination rates for flu, COVID-19 are lagging. Oct. 22, 2024.
7 CDC. Influenza and COVID-19 vaccination coverage among health care personnel – United States, 2023-24 influenza season