NCT07347002

Observational Study to Assess the Effectiveness of VLA1553 Vaccine in Preventing Chikungunya During a Pilot Vaccination Strategy in Brazil

A Test-Negative Case-control Study to Evaluate the Effectiveness of VLA1553 Against Chikungunya Virus Disease During a Pilot Vaccination Strategy in Brazil

• Status: Enrolling By Invitation
• Phase: —
• Study type: Observational
• Enrollment: 1,200 (estimated)
• Sponsor: Valneva Austria GmbH · Industry
• Sex: All
• Age: 18 Years – 59 Years
• Healthy volunteers: Accepted

Summary

This is an observational, non-interventional, test-negative case-control (TNCC) study to estimate the vaccine effectiveness of VLA1553 against Chikungunya virus in a real-world setting.

Detailed description

The objective of this study is to evaluate the effectiveness of vaccination with VLA1553 in the prevention of laboratory-confirmed symptomatic cases of CHIK after a single dose of VLA1553 administered as part of a pilot vaccination strategy following licensure in Brazil. The study will commence following the implementation of the pilot vaccination strategy in selected municipalities. Data for the analyses will be obtained from official Brazilian Ministry of Health surveillance systems, specifically the GAL (Laboratory Environment Management System), SINAN (Notifiable Diseases Information System), and Si-PNI (National Immunization Program Information System).

Conditions

• Chikungunya Virus Infection

Interventions

Type	Name	Description
BIOLOGICAL	Live-attenuated CHIKV vaccine VLA1553	Non-interventional study: VLA1553 is used in the pilot vaccination strategy which is linked to this observational study.

Timeline

• Start date: 2026-02-02
• Primary completion: 2027-12-31
• Completion: 2027-12-31
• First posted: 2026-01-16
• Last updated: 2026-02-11

Locations

4 sites across 1 country: Brazil