VLA1553-403 Pregnancy Surveillance Study

NCT07414524 | Not Yet Recruiting DMC

• 1 other identifier: VLA1553-403
• Study Type: observational
• Target: 200
• Locations: 0 countries
• Sites: N/A

Brief Summary

This post-marketing, observational study evaluates pregnancy and infant outcomes up to 12 weeks after delivery among women who received the chikungunya vaccine (VLA1553) during pregnancy or within 30 days before their last menstrual period. A matched comparator cohort of pregnant women vaccinated with routine, pregnancy-recommended vaccines (not exposed to VLA1553) is included. No study procedures beyond routine care are performed.

Conditions

Chikungunya Virus Infection

Outcome Measures

Primary Outcomes (2)

• Frequency (n,%) of individuals with any outcome (pregnancy and infant health), as described in the protocol.

  Pregnancy and infant outcomes will be collected as follows: 1. Pregnancy outcomes: stillbirths, pregnancy terminations (spontaneous and elective), preterm deliveries, neonatal deaths and term live births. 2. Infant outcomes: births small for gestational age, major congenital malformations.

  Study start through study completion, an average of 12 months

• Frequency (n,%) of specific outcomes (pregnancy and infant health), as described in the protocol.

  Pregnancy and infant outcomes will be collected as follows: 1. Pregnancy outcomes: stillbirths, pregnancy terminations (spontaneous and elective), preterm deliveries, neonatal deaths and term live births. 2. Infant outcomes: births small for gestational age, major congenital malformations.

  Study start through study completion, an average of 12 months

Secondary Outcomes (4)

• Frequency (n,%) of individuals with any outcome (pregnancy and infant health), as described in the protocol in the VLA1553 group and the control group.

  Study start through study completion, an average of 12 months

• Frequency (n,%) of specific outcomes (pregnancy and infant health), as described in the protocol in the VLA1553 group and the control group.

  Study start through study completion, an average of 12 months

• Relative risk (RR) of any outcome (pregnancy and infant health) between pregnant women vaccinated with VLA1553 and pregnant women vaccinated with other vaccines recommended during pregnancy, as described in the protocol.

  Study start through study completion, an average of 12 months

• Frequency (n,%) of individuals with SAEs (women and infants), following vaccination with VLA1553 or a control vaccine.

  Study start through study completion, an average of 12 months

Study Arms (2)

VLA1553 group

Women vaccinated with the chikungunya virus vaccine (VLA1553) anytime during their pregnancy or within 30 days preceding their last menstrual period.

Biological: Live-attenuated CHIKV vaccine VLA1553

Control group

Women who have received vaccine(s) approved for use during pregnancy by the MoH and who meet the matching criteria.

Biological: Vaccine(s) approved for use during pregnancy by the MoH

Interventions

Live-attenuated CHIKV vaccine VLA1553 BIOLOGICAL

Non-interventional study: VLA1553 is used in the pilot vaccination strategy which will start along with this observational study.

VLA1553 group

Vaccine(s) approved for use during pregnancy by the MoH BIOLOGICAL

Vaccine(s) approved for use during pregnancy by the MoH

Control group

Eligibility Criteria

• Age: 18 Years+
• Gender Eligibility Details: Females of child-bearing potential
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

The control group will consist of women who have received vaccine(s) approved for use during pregnancy by the MoH and who meet the matching criteria.

You may qualify if:

• VLA1553 vaccinated population:
• Women who have received the single dose of the VLA1553 vaccine during pregnancy or within the 30 days prior to the first day of the last menstrual period.
• Pregnant at the time of enrolment in the study.
• The participant understands and agrees to comply with the study procedures.
• Control group:
• Pregnant at the time of enrolment in the study.
• Women who have received vaccine(s) approved for use during pregnancy by the MoH and who meet the matching criteria described in the protocol.
• The participant understands and agrees to comply with the study procedures.
• Women who have not received the VLA1553 vaccine during pregnancy or within the 30 days prior to the first day of the last menstrual period.

You may not qualify if:

• Women who do not provide informed consent.
• Women who are not part of the target population of the pilot vaccination strategy at the time of vaccination.

Sponsors & Collaborators

• Valneva Austria GmbH: lead
• Butantan Foundation: collaborator
• Coalition for Epidemic Preparedness Innovations: collaborator

MeSH Terms

Conditions

Chikungunya Fever

Condition Hierarchy (Ancestors)

Alphavirus Infections; Arbovirus Infections; Vector Borne Diseases; Infections; Mosquito-Borne Diseases; Virus Diseases; Togaviridae Infections; RNA Virus Infections

Central Study Contacts

Valneva Late-Stage Clinical Development

CONTACT

+43 1 206 20 0; office@valneva.com

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: February 9, 2026
• First Posted: February 17, 2026
• Study Start: March 31, 2026
• Primary Completion (Estimated): December 31, 2027
• Study Completion (Estimated): December 31, 2027
• Last Updated: February 17, 2026

Record last verified: 2026-02