TerminatedPhase 3

Co-administration Study of an Investigational Live-Attenuated Respiratory Syncytial Virus Vaccine in Infants and Toddlers

Stopped: Sponsor decision

United States, Mexico, Puerto Rico2,226 participantsStarted 2024-05-13

Plain-language summary

This study is a Phase III, randomized, single-blind, placebo-controlled, multi-center study to be conducted in healthy infants and toddlers which will be enrolled at approximately 6 months of age (Cohort 1) and approximately 12 months of age (Cohort 2). The primary objective of the study will be to assess non-inferiority of the RSV infant and toddler (RSVt) vaccine antibody response when administered concomitantly with routine pediatric vaccines at 6 months of age (Diphtheria and Tetanus Toxoids and Acellular Pertussis, Inactivated Poliovirus, Haemophilus b Conjugate and Hepatitis B Vaccine \[Vaxelis® or Pentacel® and Recombivax HB®\] Prevnar 20®, and RotaTeq®), and 12 months of age (M-M-R II, VARIVAX, and Prevnar 20 or per local country recommendations) compared to when administered non-concomitantly.

Who can participate

Age range

6 Months – 12 Months

Sex

ALL

See this in plain English?

AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.

Inclusion Criteria: * Aged 6 months for Cohort 1 and 12 months for Cohort 2 on the day of inclusion ("6 months" means from the day of the 6-month birthday to the day before the 7-month birthday and "12 months" means from the day of the 12-month birthday to the day before the 13-month birthday) * Participants who are healthy as determined by medical evaluation including medical history and physical examination * For Cohort 1: Infant received doses of vaccines containing hepatitis B, diphtheria, tetanus, pertussis, Haemophilus influenzae type B (Hib), and inactivated poliovirus vaccine (IPV) antigens, with Advisory Committee on Immunization Practice (ACIP) recommended vaccines. The last dose(s) of these vaccines must be at least 28 days before the first study visit * Infant received the recommended doses of a recommended pneumococcal conjugate vaccine (as per local schedule) at least 28 days before the first study visit. Exclusion Criteria: * Known or suspected congenital or acquired immunodeficiency; or receipt of immunosuppressive therapy, such as anti-cancer chemotherapy or radiation therapy, within the preceding 6 months; or long-term systemic corticosteroid therapy (prednisone or equivalent for more than 2 consecutive weeks within the past 3 months) * Known previous infection with diphtheria, tetanus, Hib, measles, mumps, rubella, rotavirus, pneumococcus, polio, hepatitis B virus * Known systemic hypersensitivity to any of the study intervention components, or history o…

Questions worth asking your doctor

Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.

1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?

Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.

Questions for the trial coordinator

The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.

1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?

A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.

What they're measuring

RSV A serum neutralizing antibody titers at 28 days post dose 2 (D85) Groups 1 and 3

Timeframe: Day 85

RSV B serum neutralizing antibody titers at 28 days post dose 2 (D85) Groups 1 and 3

Timeframe: Day 85

RSV A serum neutralizing antibody titers at Day 113 Groups 2 and 4

Timeframe: Day 113

RSV B serum neutralizing antibody titers at Day 113 Groups 2 and 4

Timeframe: Day 113

Trial details

NCT IDNCT06397768

SponsorSanofi Pasteur, a Sanofi Company

Sponsor typeINDUSTRY

Study typeINTERVENTIONAL

Primary completion2025-09-18

View on ClinicalTrials.gov More RSV Immunization trials

Plain-language summary

Who can participate

Age range

6 Months – 12 Months

Sex

ALL

See this in plain English?

AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.

What they're measuring

RSV A serum neutralizing antibody titers at 28 days post dose 2 (D85) Groups 1 and 3

Timeframe: Day 85

RSV B serum neutralizing antibody titers at 28 days post dose 2 (D85) Groups 1 and 3

Timeframe: Day 85

RSV A serum neutralizing antibody titers at Day 113 Groups 2 and 4

Timeframe: Day 113

RSV B serum neutralizing antibody titers at Day 113 Groups 2 and 4

Timeframe: Day 113