Vaccine Info

VLA1553 Chikungunya Vaccine


VLA1553 is a monovalent, single dose, live-attenuated vaccine candidate.


VLA1553 is indicated for the protection against chikungunya.


VLA1553 is administered intramuscularly.  The dosing is being evaluated in Phase 1 clinical trial


May 22, 2019: Phase 1 unblinded results up to month 7 showed excellent immunogenicity and safety profile confirming Valneva's unique, single-shot vaccine candidate.

These results strongly support further development acceleration

  • VLA1553 was generally safe in all dose groups
    • Well-tolerated in the low and medium dose. (Superior safety profile, including viremia, compared to the high dose group)
    • Excellent local tolerability
  • Excellent immunogenicity profile in all dose groups after a single vaccination
    • 100% Seroconversion1 achieved at Day 14 after a single vaccination in all dose groups
    • Sustained at 100% after six months

May 2, 2019: Valneva reported positive Phase 1 interim results for, VLA1553, its chikungunya vaccine candidate.

  • The interim results showed an excellent immunogenicity profile after a single vaccination with a 100% seroconversion rate achieved at Day 28 in a pooled analysis of all vaccinated groups.
  • Results also showed that 96.5% of subjects achieved at least a 16-fold increase in antibody titres and a high geometric mean titre, fully supporting VLA1553′s differentiated target product profile.
  • The pooled safety profile of all groups was considered acceptable, supporting further development.
  • No serious adverse events nor adverse events of special interest were reported up to Day 28 and the local tolerability was considered excellent.

December 2018: VLA1553 was granted Fast Track designation by the US Food and Drug Administration (FDA).

Clinical Trial NCT03382964:  A Phase 1 Study to Assess the Safety and Immunogenicity of a Chikungunya Virus Vaccine Candidate (VLA1553) in Healthy Volunteers

  • Randomized, observer-blinded, multicenter, dose-escalation Phase 1 clinical study investigating three dose levels of VLA1553 after a single immunization.
  • 120 study participants will be enrolled in the study to receive three different doses (30 subjects in the low and medium and 60 subjects in the high dose group). Vaccination will be given intramuscularly on Day 0.
  • As a safety precaution, the study will begin with the enrolment of 20 sentinel subjects in an open-label fashion.
  • Thereafter, subjects will be enrolled in a blinded, randomized manner in the three study arms.
  • A re-vaccination will be given at Month 6 or Month 12 to confirm that a single vaccination will be sufficient to induce high titer neutralizing antibodies and protect subjects from CHIKV viremia.
  • Study participants will be followed up until 13 months after initial vaccination.


September 30th, 2019