In short
Trosovavilp alfa is a recombinant, adsorbed chikungunya vaccine authorised as a medicine under the name VIMKUNYA. It is given as an intramuscular injection and is being studied in a Phase 3 trial in La Réunion with 1,800 participants at risk of severe chikungunya. The trial measures real-life vaccine effectiveness against confirmed chikungunya infection.
Key points
- Trosovavilp alfa is a recombinant, adsorbed vaccine against chikungunya.
- The authorised product name is VIMKUNYA, supplied by Bavarian Nordic A/S.
- A Phase 3 trial in La Réunion is enrolling 1,800 participants.
- The trial studies vaccine effectiveness in populations at risk of severe or complicated chikungunya.
- The vaccine is given as a 0.80 ml intramuscular injection.
- The trial is currently authorised and follows an ambispective design.
What is trosovavilp alfa?
Trosovavilp alfa is a vaccine against chikungunya. It is a protein-based, structurally diverse substance classified as a vaccine, with the Anatomical Therapeutic Chemical code J07BP02. The vaccine is authorised as a medicine in the European Union under the authorisation record EU/1/25/1916/001 and is supplied by Bavarian Nordic A/S. The authorised product name is VIMKUNYA, a suspension for injection in a pre-filled syringe containing the recombinant, adsorbed chikungunya vaccine. Trosovavilp alfa is the active substance in VIMKUNYA.
How does trosovavilp alfa work?
Trosovavilp alfa is a recombinant, adsorbed vaccine. Recombinant vaccines contain a protein from the virus, produced in the laboratory, that teaches the immune system to recognise and fight the chikungunya virus. The term "adsorbed" means the vaccine protein is attached to an adjuvant, a substance that strengthens the immune response. The trial record describes the mechanism in the context of measuring how well vaccination protects against confirmed chikungunya infection, defined by a positive PCR or IgM test.
Which conditions is trosovavilp alfa used or studied for?
- Chikungunya — a viral disease spread by mosquitoes that causes fever and severe joint pain. Trosovavilp alfa is authorised for use against chikungunya and is being studied in people at risk of severe or complicated disease.
How is trosovavilp alfa given?
Trosovavilp alfa is given as an intramuscular injection. The authorised product VIMKUNYA is a suspension for injection in a pre-filled syringe, and the trial uses a 0.80 ml dose. The injection is administered into the muscle, as recorded in the trial protocol.
What do the clinical trials show?
One clinical trial in the EU registry investigates trosovavilp alfa. The trial, with the EU CT number 2025-521307-43-00, is a Phase 3 study taking place in La Réunion with 1,800 participants. It is an ambispective study, meaning it looks both at data collected in the past and data collected going forward. The trial evaluates the real-life efficacy, safety, and immunogenicity of chikungunya vaccination in populations at risk of severe or complicated disease.
The primary outcome is vaccine effectiveness, defined as the difference in attack rate between unvaccinated and vaccinated participants divided by the attack rate in unvaccinated participants. The attack rate is the cumulative incidence of confirmed chikungunya at the end of the follow-up period. The trial compares VIMKUNYA, the recombinant vaccine containing trosovavilp alfa, with IXCHIQ, a live chikungunya vaccine. The study status is authorised, meaning it has received regulatory approval to begin.
What side effects are known?
The registry data provided does not include a list of side effects for trosovavilp alfa. The clinical trial is designed to evaluate safety, but specific adverse events are not listed in the available trial record.