Thank you for your interest in the study. Enrollment is closed.

For Physicians

The SAVVY study is a Phase 2b trial evaluating the safety, tolerability, and immunogenicity of a Respiratory Syncytial Virus (RSV) vaccine in pregnant women and their infants.

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Investigational Vaccine

The active ingredients in the RSV vaccine are 2 stabilized prefusion RSV F antigens, in equal amounts, from virus subgroups A and B.

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Study Qualifications

Key study eligibility criteria include:

  • 18 to 49 years of age
  • Healthy and expecting a healthy baby
  • Between 24 and 36 weeks of gestation on the day of planned vaccination
  • Receiving prenatal standard of care
  • Ultrasound at ≥ 18 weeks of pregnancy
    NOTE: If not performed at ≥ 18 weeks of pregnancy as part of prenatal standard of care, an ultrasound will be performed and reviewed as part of the screening visit
  • BMI < 40 kg/m2 at screening
  • Current pregnancy not from in vitro fertilization or other assisted reproductive technology

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Up to 650 women will be randomized 1: 1: 1: 1: 1 to receive one of 2 dose levels of RSV Vaccine, formulated with or without aluminum hydroxide (Al[OH]3), or placebo (saline solution).

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Study Participation

Eligible women will participate from enrollment during their pregnancy until approximately 12 months after delivery. Scheduled maternal study visits (8) include screening, vaccination, post-vaccination, and post-delivery visits. Maternal participants will answer questions and record their temperature and any vaccination-site swelling or redness in an electronic diary (e-diary) for 7 consecutive days at home beginning the day of vaccination.

Infants will participate from birth until approximately 12 months of age, with 5 study visits scheduled. Additional visits may be scheduled as needed. Identifier

For more information on maternal vaccines, please click on the link below.