The FDA on Aug. 21 approved Pfizer's maternal vaccine meant to protect infants from respiratory syncytial virus.
The shot, Abrysvo, is meant to protect newborns from severe disease through their first six months of life. Federal regulators approved the vaccine to be administered to expectant mothers who are between 32 and 36 weeks pregnant, which passes antibodies to the fetus.
The FDA's decision was based on data from a phase 3 trial that found the vaccine reduced the risk of severe lower respiratory tract disease from RSV by nearly 82 percent within 90 days after birth, and by 69 percent within 180 days. Abrysvo was previously approved to prevent severe disease from RSV in adults 60 and older.
An official with Pfizer told CNBC the company aims to have the vaccine available to the public by October, pending sign off and recommendations from the CDC. The vaccine is already available for older adults.