NCT06106581

A Phase 2 Clinical Trial of VLA1553 in Healthy Children Aged 1 to 11 Years

A Randomized, Observer-blinded, Dose Response Phase 2 Trial to Assess the Safety and Immunogenicity of Two Different Dose Levels of a Live-attenuated Chikungunya Virus Vaccine (VLA1553) in Healthy Children Aged 1 to 11 Years

• Status: Completed
• Phase: Phase 2
• Study type: Interventional
• Enrollment: 304 (actual)
• Sponsor: Valneva Austria GmbH · Industry
• Sex: All
• Age: 1 Year – 11 Years
• Healthy volunteers: Accepted

Summary

This is a multicenter, prospective, randomized, observer-blinded, three arm, phase 2 clinical trial evaluating the full dose formulation of VLA1553, half dose formulation of VLA1553 and control. At least 300 male and female healthy children aged 1 to 11 years will be enrolled and the overall distribution of participants will be 2:2:1 to the two VLA1553 dose groups (n=120 each) or control (n=60).

Detailed description

This is a multicenter, prospective, randomized, observer-blinded, three arm, phase 2 clinical trial evaluating the full dose formulation of VLA1553, half dose formulation of VLA1553 and control (Nimenrix, a tetravalent meningococcal vaccine - Men ACWY). At least 300 male and female healthy children aged 1 to 11 years will be enrolled and the overall distribution of participants will be 2:2:1 to the two VLA1553 dose groups (n=120 each) or control (Nimenrix) (n=60). As a safety precaution measure, the first 30 sentinel participants will be enrolled into the trial in an open-label fashion according to an age step down scheme. After sentinel analysis, participants will be enrolled in a blinded, randomized manner into three Trial Arms. Within each treatment arm participants will be stratified into three age strata: Stratum A: 7 to 11 years -children from their 7th birthday until the day before their 12th birthday. Stratum B: 3 to 6 years - children from their 3rd birthday until the day before their 7th birthday. Stratum C: 1 to 2 years - children from their 1st birthday until the day before their 3rd birthday. Age strata for the VLA1553 treatment arms are targeted to be equal in size, i.e., approximately 40 per age stratum.

Conditions

• Chikungunya Virus Infection

Interventions

Type	Name	Description
BIOLOGICAL	VLA1553 full dose	Single intramuscular vaccination on Day 1 with VLA1553 full dose, a lyophilized live-attenuated Chikungunya vaccine candidate
BIOLOGICAL	VLA1553 half dose	Single intramuscular vaccination on Day 1 with VLA1553 half dose, a lyophilized live-attenuated Chikungunya vaccine candidate
BIOLOGICAL	Control	Nimenrix

Timeline

• Start date: 2023-12-18
• Primary completion: 2024-07-31
• Completion: 2025-07-02
• First posted: 2023-10-30
• Last updated: 2025-08-08

Locations

3 sites across 2 countries: Dominican Republic, Honduras

Regulatory

• FDA-regulated drug study