Valneva presents positive Phase III results for Chikungunya vaccine candidate

French vaccines developer Valneva (Euronext Paris: VLA) gained as much as 5% to 12.40 euros yesterday, as it announced positive top-line results from the Phase III pivotal trial of its single-shot chikungunya vaccine candidate, VLA1553, which was recently awarded Breakthrough Designation status by the Food and Drug Administration.

The trial, involving 4,115 adults, aged 18 years and above, across 44 sites in the USA, met its primary endpoint inducing protective CHIKV neutralizing antibody titers in 98.5% of participants 28 days after receiving a single shot (264 of 268 subjects from the per-protocol subgroup tested for immunogenicity, 95%CI: 96.2-99.6). The seroprotection rate result of 98.5% exceeded the 70% threshold (for non-acceptance) agreed with the FDA.

The seroprotective titer was agreed with the FDA to serve as a surrogate of protection that can be utilized in a potential FDA submission of VLA1553 under the accelerated approval pathway. The vaccine candidate was highly immunogenic with a GMT of approximately 3,270, confirming the immunogenicity profile seen in the Phase I trial, said Valneva.