Osivax has reported phase 2b results for OVX836 and outlined the next stage of development for its next-generation seasonal influenza vaccine strategy.
The study evaluated OVX836 in 2,850 healthy adults in Europe and delivered what the company describes as the first consistent efficacy signal for a monovalent nucleoprotein-based influenza vaccine across both major influenza A subtypes.
The trial did not meet its pre-specified primary endpoint of 50% vaccine efficacy, with a point estimate of 24% that was not statistically significant.
Secondary endpoints showed emerging efficacy signals, including 28% for CDC-defined influenza-like illness, 27% for A/H3 and 25% for A/H1N1pdm09. OVX836 also demonstrated a favourable safety profile and induced robust NP-specific antibody and T-cell responses. Osivax said these findings support advancing OVX836 in combination with traditional seasonal influenza vaccines to provide a complementary layer of protection.
Dr Nicola Groth said: “Large efficacy studies are designed not only to evaluate clinical benefit, but also to deepen our understanding of novel immune mechanisms under real-world conditions.”
She added: “While the study did not meet its primary endpoint, the consistency of the efficacy signal across influenza A subtypes, together with the observed immunogenicity and favourable safety profile, reinforces our confidence that nucleoprotein-targeted immunity can provide a complementary mechanism of protection alongside conventional seasonal influenza vaccines.”
Alexandre Le Vert said: “These results provide a clear direction for the future development of OVX836. Rather than replacing existing seasonal influenza vaccines, we believe the greatest opportunity lies in complementing them.”
He added: “By combining strain-specific antibody protection with the broad cellular immunity induced by OVX836, we aim to develop next-generation influenza vaccines capable of delivering broader and more durable protection against seasonal influenza.”
Osivax has secured collaborations with GC Biopharma and a second undisclosed pharmaceutical partner to support development of single-injection combination candidates. The first phase 1/2 combination study is expected in Q4 2027.
