An observational study in Chikungunya Virus Infection, sponsored by Valneva Austria GmbH. Active, not recruiting at 3 sites in Brazil. Open to participants aged 18 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-07-21.
Sponsored by Valneva Austria GmbH · Observational
This is an observational study with primary data collection, which will combine a prospective safety cohort study and an SCRI study.
This prospective safety cohort study will be conducted in selected Brazilian municipalities participating in a pilot vaccination strategy. A total of 5,000 participants will be recruited. The primary objective is to estimate the incidence rates of a predefined set of AEs which constitute safety concerns. The secondary objectives are to measure the relative risk associated with VLA1553 administration for a predefined set of AEs which constitute safety concerns, and to assess the frequency of occurrence of any collected AE which are medically attended or meet the criteria of seriousness This study also aims to investigate VLA1553's safety in underrepresented populations by collecting all AEs, not just AEs which constitute safety concerns.
84 studies on the registry are indexed under Chikungunya Fever; 18 are open to participants now.
This study's planned enrollment of 5,000 is above the median of 570 across 25 observational studies indexed under Chikungunya Fever.
Browse Chikungunya Fever studies →Valneva Austria GmbH is the lead sponsor of 44 studies on the registry; 2 are open to participants now.
Of its 7 completed or terminated interventional studies of FDA-regulated products, 4 (57%) have results posted.
Counted across the registry records on this site, refreshed daily.
This study will collect data from approximately 5,000 individuals who received VLA1553, as per label, as part of the pilot vaccination strategy in selected municipalities in Brazil.
Exclusion Criteria:
Non-interventional study: VLA1553 is used in the pilot vaccination strategy which will start along with this observational study.
To estimate the incidence rates of a predefined set of AEs which constitute safety concerns according to the VLA1553 Risk Management Plan following the administration of the live-attenuated VLA1553 vaccine
For each safety concern, the risk windows after VLA1553 administration are defined as: 1. 30 days for Chikungunya-like adverse reactions; 2. 60 days for cardiac events, choosing a more conservative window than the 42 days suggested by the Brighton Collaboration recommendations on myocarditis; 3. 60 days for arthritis to account for late-onset or potentially immune-mediated cases
Time frame: From enrollment until Day 60
To measure the relative risk associated with VLA1553 administration for a predefined set of AEs which constitute safety concerns as per the VLA1553 Risk Management Plan for those AEs that have a defined risk window following vaccination.
Time frame: From enrollment until Day 120
To assess the frequency of occurrence of predefined AEs which are medically attended or meet the criteria of seriousness.
1. Frequency of occurrence of predefined chronic chikungunya-like adverse reactions; 2. frequency of predefined SAEs; 3. frequency of occurrence of arthralgia; 4. frequency of occurrence of prolonged arthralgia; 5. frequency of predefined CHIKV infection symptoms; 6. frequency of occurrence of predefined chronic CHIKV infection symptoms
Time frame: From enrollment until Month 6
To assess the frequency of occurrence of AEs (not exclusively those of safety concern) following VLA1553 vaccination when co-administered or concomitantly administered with other vaccines.
Time frame: From enrollment until Month 6
To assess the frequency of occurrence of AEs (not exclusively those of safety concern) in populations underrepresented or excluded in clinical trials with VLA1553.
1. Individuals aged ≥ 65 years old (including those with chronic medical conditions); 2. individuals with acute or progressive, unstable, or uncontrolled clinical conditions; 3. individuals with autoimmune or inflammatory disorders (including with impaired or dysregulated immune responses);
Time frame: From enrollment until Month 6
Plan to share: Undecided
No publications or documents are linked to this record.
This study is active, not recruiting, as verified in Jul 2026. You cannot join it, but the record below documents what was studied.
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Valneva Austria GmbH