Novavax COVID-19-Influenza Combination Vaccine Candidate Shows Promise in Early Trial

Positive results from a phase 1/2 clinical trial of Novavax’s COVID-19-influenza combination (CIC) vaccine candidate showed the vaccine is able to produce an immune response, including both antibody and polyfunctional CD4+ T-cell responses against SARS-CoV-2 and homologous and heterologous influenza strains.

The CIC vaccine formulation was found to induce polyfunctional CD+4 T-cell responses against both SARS-CoV-2 and homologous and heterologous influenza strains at levels comparable to the standalone NVX-CoV2373 vaccine and quadrivalent influenza vaccine candidate reference formulations. NVX-CoV2373 has previously been found to induce functional SARS-CoV-2-specific CD4+ and CD8+ T-cell responses.

NVX-CoV2373 is a protein-based vaccine that was engineered from the genetic sequence of the first strain of SARS-CoV-2 and was formulated with the Novavax’s patented saponin-based Matrix-M adjuvant, which enhances the immune response and stimulated high levels of neutralizing antibodies. In the phase 3 PREVENT-19 trial, the recombinant nanoparticle protein-based vaccine was found to provide 100% protection against moderate and severe disease and 90.4% efficacy overall.

During the trial, investigators enrolled 29,960 people across 119 sites in the United States and Mexico to assess the efficacy, safety, and immunogenicity of the vaccine. Data from the trial demonstrated that NVX-CoV2373 met its primary endpoint with an overall efficacy of 90.4% (95% CI: 82.9, 94.6). During the trial, 77 cases of COVID-19 were observed, with 63 in the placebo group and 14 in the vaccine group. The observed cases in the vaccine group were mild and in the placebo group there were 10 moderate cases and 4 severe cases observed, translating to a vaccine efficacy of 100% (95% CI: 87, 100) against moderate or severe disease.

Novavax’s quadrivalent influenza vaccine candidate has previously induced cross-reactive polyfunctional CD4+ T-cell responses, according to a company press release.

The safety and tolerability profile of CIC was consistent with the standalone NVX-CoV2373 prototype vaccine and quadrivalent influenza vaccine candidate reference formulations in the trial. The candidate vaccine was generally well-tolerated with serious adverse events, none of which were assessed as related to the vaccine, according to Novavax.

"[The] results demonstrate that our COVID-19-Influenza Combination vaccine candidate is feasible, well-tolerated, and immunogenic, inducing both antibody and T-cell responses," said Gregory M. Glenn, MD, president of Research and Development, Novavax, in a press release. "As we transition from a SARS-CoV-2 pandemic to endemic circulation, we believe our protein-based combination vaccine candidate can help address two global public health threats with one vaccine."

The phase 1/2 CIC vaccine trial evaluated a combination of NVX-CoV2373 and patented saponin-based Matrix-M adjuvant in a single formulation. The trial analyzed the safety, tolerability, and immune response to the CIC in 642 healthy adults 50 to 70 years of age. The participants were either previously infected with SARS-CoV-2 or vaccinated with an authorized vaccine approximately 8 weeks prior to enrollment.

Both protein-based vaccines used in the trial were formulated with the saponin-based Matrix-M adjuvant.

In July, the FDA granted emergency use authorization to the NVX-CoV2373 2-dose primary series for individuals 18 years of age and older.

REFERENCE

Novavax COVID-19-Influenza Combination Vaccine Candidate Induced Antibody and T-Cell Responses Against SARS-CoV-2 and Homologous and Heterologous Influenza Strains. Novavax. October 13, 2022. Accessed October 14, 2022. https://ir.novavax.com/2022-10-13-Novavax-COVID-19-Influenza-Combination-Vaccine-Candidate-Induced-Antibody-and-T-Cell-Responses-Against-SARS-CoV-2-and-Homologous-and-Heterologous-Influenza-Strains