Novavax’s combination COVID-19 & Flu vaccine shows promise in elderly trial

USA—Novavax has announced encouraging early results from its phase 3 trial of two vaccines aimed at protecting older adults against respiratory infections.

The study tested a combination vaccine targeting both COVID-19 and influenza, called CIC, alongside a stand-alone influenza vaccine, known as tNIV.

The trial focused on adults aged 65 and older, a group particularly vulnerable to severe respiratory infections.

The trial enrolled about 2,000 participants and found that both vaccines generated strong immune responses while being well tolerated.

Specifically, the vaccines elicited neutralising antibodies against multiple influenza strains—H1N1, H3N2, and B—as well as against SARS-CoV-2, the virus responsible for COVID-19.

Antibody levels increased by a factor of between 2.4 and 5.7 compared to baseline measurements.

These immune responses were comparable to those observed with established vaccines such as Fluzone High-Dose (HD) for influenza and Nuvaxovid for COVID-19.

Importantly, the safety profiles of the new vaccines were similar to those of the licensed products, with over 98% of reported side effects being mild or moderate.

 No serious adverse events related to the vaccines were reported during the trials, supporting their continued development.

Although the study was not designed to provide definitive statistical comparisons, the descriptive data offer valuable insights.

Novavax plans to use these findings to guide the design of its upcoming Phase 3 registrational program and to support ongoing partnership discussions.

These phase 3 results build on earlier phase 2 data, which showed that Novavax’s CIC vaccine, its stand-alone influenza vaccine, and a high-dose COVID-19 vaccine candidate all produced robust immune responses and were well tolerated in adults aged 50 to 80 years.

Notably, the stand-alone flu vaccine outperformed other influenza vaccines such as Fluad (Seqirus) and Fluzone HD (Sanofi) in hemagglutination inhibition (HAI) responses—a key measure of flu vaccine effectiveness.

It showed 31% to 56% higher antibody titers for all tested strains and up to 89% higher titers specifically for A strains.

Meanwhile, the CIC vaccine induced antibody levels similar to Novavax’s original COVID-19 vaccine and flu responses comparable to authorized vaccines.

The high-dose COVID-19 vaccine candidate elicited IgG and neutralizing antibody responses approximately 30% higher than the prototype vaccine, while maintaining a similar safety and side effect profile.

Overall, these promising findings have informed the ongoing phase 3 trial design and strengthen Novavax’s position in the competitive vaccine market for respiratory diseases affecting older adults.

 The company’s continued progress offers hope for more effective combined vaccines that can protect vulnerable populations against multiple respiratory viruses simultaneously.