Combination Influenza and COVID-19 Vaccine Candidates Granted Fast Track Designation

The FDA recently granted Fast Track designation to the first non-mRNA combination vaccine candidates of vaccines that have already been licensed to prevent the respiratory diseases influenza and COVID-19 among individuals 50 years and older.¹

These findings highlight the critical importance of flu and COVID-19 vaccination in protecting older populations and reducing the severe consequences of these diseases. Image credit: Eagle - stock.adobe.com

Fast Track designation was granted with the aim of addressing the significant individual and health system burdens of these 2 illnesses, which can lead to hospitalization and even death, especially among older adults.

“Building on our immunology expertise and on 12 years of robust clinical and real-world data, we aim to continue leading the way in protection against flu and its severe outcomes,” said Thomas Triomphe, executive vice president, vaccines, Sanofi, in a statement. “Our goal is to develop a combined flu and COVID-19 vaccine that offers simpler scheduling and fewer injections without compromising on the industry leading levels of efficacy, safety and tolerability of the standalone vaccines included in our combination vaccine.”

The first vaccine candidate (NCT06695117) is comprised of the influenza protein-based trivalent vaccine Fluzone High-Dose combined with the adjuvanted recombinant Novavax COVID-19 vaccine. The second candidate (NCT06695130) includes the influenza recombinant protein-based trivalent vaccine Flublok with the Novavax COVID-19 vaccine.

Both vaccines have been proven to prevent more influenza infections in older adults than standard-dose influenza vaccines and have demonstrated significant and consistent reductions in flu-related hospitalizations in real-world evidence studies. Additionally, the Novavax COVID-19 vaccine has shown a favorable tolerability profile compared with the currently available mRNA COVID-19 vaccines when administered as a booster dose and has also demonstrated high efficacy against COVID-19 as primary vaccination in 2 pivotal phase 3 studies.

Sanofi has begun separate phase 1/2 parallel, randomized, modified double-blind, multi-arm studies to evaluate the safety and immune response induced by the 2 combination vaccine candidates.

Combination vaccines play a critical role in enhancing immunization efforts by offering protection against multiple diseases with a single injection. Recent evidence underscores their potential to boost vaccine uptake, particularly among older adults. A systematic review and meta-analysis found that a combination booster vaccine could increase COVID-19 vaccine uptake by 56% in individuals 50 years and older. These vaccines streamline the immunization process by reducing the number of shots required, leading to less pain and discomfort, as well as less time off from work or family.²

Influenza Vaccination

Influenza poses a significant threat to older adults, particularly those 65 years and older, who account for most flu-related hospitalizations.¹ In this age group, flu often results in a higher hospitalization rate, with hospital stays averaging twice as long as those of younger adults, and nearly one-quarter of patients are readmitted within 90 days post discharge. Beyond hospitalization, flu can disrupt major organ systems, increasing the risk of complications such as an 8-fold rise in stroke and pneumonia risk and a 10-fold rise in heart attack risk. Among those hospitalized, 1 in 5 older adults suffers a decline in their ability to perform basic daily activities, such as bathing and dressing.

COVID-19 Vaccination

COVID-19 remains a significant global health challenge. While most individuals experience mild to moderate respiratory illness and recover without complications, severe cases can result in hospitalization or death. Beyond the acute phase, many people face the burden of long COVID, a condition with a range of symptoms affecting multiple organ systems, complicating diagnosis and management, and often resembling other illnesses.³ A meta-analysis of 12 studies revealed that 30% of patients with COVID-19 continue to experience symptoms 2 years post infection, with fatigue, cognitive impairment, and pain being the most common.¹

These findings highlight the critical importance of flu and COVID-19 vaccination in protecting older populations and reducing the severe consequences of these diseases.

References

1. Two combination vaccine candidates for prevention of influenza and COVID-19 granted Fast Track designation in the US. Sanofi. Press release. December 11, 2024. Accessed December 16, 2024. https://www.sanofi.com/en/media-room/press-releases/2024/2024-12-11-06-00-00-2995072

2. Combination vaccines. CDC. July 2, 2024. Accessed December 16, 2024. https://www.cdc.gov/vaccines-children/about/combination-vaccines.html.

3. Steinzor P. 5 things you should know about long covid. AJMC. November 22, 2024. Accessed December 16, 2024. https://www.ajmc.com/view/5-things-you-should-know-about-long-covid