Chikungunya Virus InfectionPhase 3NCT04838444
Antibody Persistence And Long Term Safety Of A Chikungunya Virus Vaccine (VLA1553)
A Phase 3 study testing VLA1553 in people with Chikungunya Virus Infection, run by Valneva Austria GmbH at 10 sites in United States.
Trial summary
In this open-label Phase 3b, single arm trial, persistence of antibodies and long term safety will be evaluated in up to 375 participants rolled over from trial VLA1553-301 (NCT number: NCT04546724). Read more about this study
- Who is it for?
- Ages 18 years and olderHealthy volunteers can take part
- Conditions the study is for
- Chikungunya Virus Infection
- What is being tested?
- VLA1553
- Type of treatment
- Vaccines
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 363 participants
- Where
- 10 sitesUnited States
- Study dates
- 2 Apr 2021to May 2031
- Phase
- Phase 3
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Who may be able to join
- Individual participated in the VLA1553-301 clinical trial;
- Participant has an understanding of the trial and its procedures, agrees to its provisions, and voluntarily gives written informed consent prior to any trial-related procedures;
- Participant had immunogenicity blood samples taken at baseline (Visit 1) and either Day 29 (Visit 3), Day 85 (Visit 4) or Day 180 (Visit 5) in Trial VLA1553-301 and was negative for neutralizing antibodies at baseline
Who cannot join
- Participant presents with clinical conditions representing a contraindication to blood draws;
- Participant has donated blood or use of blood products prior 30 days of immunogenicity sampling;
- Participant has received an active drug with potential immunosuppressive action or investigational drug or device within a period of 30 days prior a trial visit;
- Participant has a known or suspected problem with alcohol or drug abuse as determined by the Investigator;
- Participant has any condition that, in the opinion of the Investigator, may compromise the participant's well-being, might interfere with evaluation of trial endpoints, or would limit the participant's ability to complete the trial;
- Participant is committed to an institution (by virtue of an order issued either by the judicial or the administrative authorities);
- Participant is a member of the team conducting the trial or in a dependent relationship with one of the trial team members. Dependent relationships include close relatives (i.e., children, partner/spouse, siblings, parents) as well as employees of the Investigator or site personnel conducting the trial.
Trial locations and contacts
10 sites in 1 country.
10 sites in 1 country
United States10 sites
Velocity Clinical Research
Austin, Texas, 78759
Accelerated Enrollment Solutions (AES)
Chicago, Illinois, 60602
Velocity Clinical Research
Grand Island, Nebraska, 68803
Velocity Clinical Research
Hallandale, Florida, 33090
Alliance for Multispecialty Research (AMR)
Knoxville, Tennessee, 37920
Alliance for Multispecialty Research (AMR)
Lexington, Kentucky, 40509
Allliance for Multispecialty Research (AMR)
Norfolk, Virginia, 23502
Velocity Clinical Research
Omaha, Nebraska, 68134
Accelerated Enrollment Solutions (AES)
Phoenix, Arizona, 85020
Velocity Clinical Research
West Jordan, Utah, 84088
About this study
Official title: An Open-Label, Single Arm Trial To Evaluate Antibody Persistence And Long Term Safety Of A Live-Attenuated Chikungunya Virus Vaccine (VLA1553) In Adults Aged 18 Years and Above
In this open-label Phase 3b, single arm trial, persistence of antibodies and long term safety will be evaluated in up to 375 participants rolled over from trial VLA1553-301 (NCT number: NCT04546724).
Read the detailed description
In this open-label Phase 3b, single arm trial, persistence of antibodies and long term safety in up to 375 participants rolled over from trial VLA1553-301 (NCT number: NCT04546724)
These participants will have annual follow-up visits at Months 12, 24, 36, 48, 60, 72, 84, 96, 108 and 120 after immunization. The primary objective of this trial will be to evaluate persistence of antibodies annually from 1 to 10 years after the single immunization with VLA1553. The secondary objective is to evaluate long-term safety 6 months to 2 years after the single immunization with VLA1553.
- Conditions
- Chikungunya Virus Infection
- Being tested
- VLA1553
- Medical subject headings
- Chikungunya Fever
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
VLA1553Biological
Trial participants previously vaccinated with VLA1553 in trial VLA1553-301 will be followed up for safety and immunogenicity.
| Study group | Role | What they receive |
|---|---|---|
| VLA1553 | Experimental | Not described Receives: Biological: VLA1553 |
What is being measured
The primary outcome is the main question the study is designed to answer.
Proportion of Participants With Seroresponse Levels Post-vaccination. (Defined as µPRNT50 ≥150)
Data for Visit 1 - Day 1 are collected from Trial VLA1553-301
Measured: Year 2
Secondary outcomes (6)
Frequency of Any Serious Adverse Event (SAE)
Measured: until Year 2
Relatedness of Any Serious Adverse Event (SAE)
Measured: until Year 2
Immune Response as Measured by CHIKV-specific Neutralizing Antibody Titers Post-vaccination
Measured: until Year 10
Proportion of Participants With Seroconversion
Measured: until Year 10
Fold Increase of CHIKV-specific Neutralizing Antibody Titers Post-vaccination as Compared to Baseline (i.e. at Start of Trial VLA1553-301)
Measured: until Year 10
Proportion of Participants Reaching an at Least 4-fold, 8-fold, 16-fold or 64-fold Increase in CHIKV-specific Neutralizing Antibody Titer Compared to Baseline
Measured: until Year 10
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted9 Apr 2021
- Study start2 Apr 2021
- Primary completion3 Mar 2023
- Study completionMay 2031 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Chikungunya Virus InfectionStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 3
- Primary purpose
- Prevention
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 363 participants (actual)
Sponsor and investigators
- Lead sponsor
- Valneva Austria GmbH
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Valneva Clinical Development, Study chair, Valneva Austria GmbH
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04838444
- Sponsor's protocol ID
- VLA1553-303
- Status last verified
- Aug 2025
- First submitted
- 6 Apr 2021
- Last updated
- 9 Jul 2026
- Results posted
- Yes, on ClinicalTrials.gov
- Data monitoring committee
- Yes
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- Yes: After trial completion, Valneva may provide access to individual de-identified participant data and related trial documents (e.g. protocol, Statistical Analysis Plan (SAP), Clinical Trial Report (CTR)) upon request from qualified researchers, and subject to Valneva's review and approval.
Publications
McMahon R, Toepfer S, Sattler N, Schneider M, Narciso-Abraham M, Hadl S, Hochreiter R, Kosulin K, Mader R, Zoihsl O, Wressnigg N, Dubischar K, Buerger V, Eder-Lingelbach S, Jaramillo JC. Antibody persistence and safety of a live-attenuated chikungunya virus vaccine up to 2 years after single-dose administration in adults in the USA: a single-arm, multicentre, phase 3b study. Lancet Infect Dis. 2024 Dec;24(12):1383-1392. doi: 10.1016/S1473-3099(24)00357-8. Epub 2024 Aug 12.
PubMed 39146946