Maternal immunization with investigational RSV vaccine conferred protection to infants - Contemporary Pediatrics
An investigational vaccine against respiratory syncytial virus (RSV) administered to pregnant women in a phase 2b trial produced sufficient maternal immunogenic response and transplacental antibody transfer for infants to demonstrate protection from birth to at least 6 months of age. The prepublication, interim results of the trial informed the Food and Drug Administration (FDA) decision in March to designate the vaccine as a Breakthrough Therapy. Alejandra Gurtman, MD, Vaccine Research and Development, Pfizer, and colleagues employed 2 strategies to improve on an earlier effort, in which inactivated whole-virus vaccine administered directly to infants actually worsened illness when initial RSV exposure occurred after vaccination: They developed an alternative to the inactivated whole-virus; and administered it to pregnant women who, along with all adults, have had previous exposure to RSV. "Adults have universally had exposure to RSV, so the immunization of pregnant women could c...