Medscape Editions Stéphanie Lavaud July 18, 2025 The Vimkunya vaccine, designed for active immunization to prevent chikungunya virus (CHIKV) infection in indivi
Medscape Editions
Stéphanie Lavaud
July 18, 2025
The Vimkunya vaccine, designed for active immunization to prevent chikungunya virus (CHIKV) infection in individuals aged 12 and older, was launched in France on June 17, as announced by its manufacturer, Bavarian Nordic, in a press release.
Vimkunya received European marketing authorization (MA) on February 28, 2025, from the European Medicines Agency (EMA) following an accelerated procedure (PRIME) due to the active circulation of the virus in certain geographical areas. French overseas territories like La Réunion are primarily affected, but mainland France is no longer spared, with 25 locally transmitted chikungunya cases identified as of July 8, 2025. The chikungunya virus is now present in over 110 countries worldwide. "This vaccine aims to meet a real need for the protection of populations and travelers," stated the laboratory.
VLP Technology Behind Vimkunya
Vimkunya is produced using a Virus-Like Particles (VLP) platform. VLPs mimic the virus in their organization and structure but are non-infectious as they do not contain viral genetic material (neither DNA nor RNA). Intramuscular administration of this vaccine triggers a specific immune response that neutralizes the chikungunya virus. Several vaccines based on VLP technology have been successfully used in global immunization programs for years, such as those for papillomavirus and hepatitis B.
Clinical Studies and Efficacy
The EMA's opinion is largely based on data from two placebo-controlled studies. Study 1 evaluated the immunogenicity and safety of the vaccine in 3,258 individuals aged 12 to 64, and Study 2 in 413 elderly individuals. The immune response was assessed in 3,355 participants (2,748 with Vimkunya and 607 with placebo). The clinical efficacy of Vimkunya was inferred from a specific CHIKV neutralizing antibody titer post-vaccination, chosen as a surrogate marker called sero-response. Eight days after vaccination, the difference in sero-response rates (SRR) between those vaccinated with Vimkunya and those who received the placebo in Study 1 was 46.1%. It increased to 96% on day 15, 96.6% on day 22, and 84% on day 183. In Study 2, the SRR difference was 79.5% on day 15, 86.2% on day 22, and 74.4% on day 183.
Safety Profile and Side Effects
The safety profile of Vimkunya is based on pooled data from five completed clinical studies involving 3,522 participants with a follow-up of 6 months. The most frequently reported side effects include fatigue, headaches, muscle pain, and pain at the injection site.
