The US Food & Drug Administration approved tetanus toxoid, reduced diptheria toxoid and acellular pertussis vaccine, adsorbed [Tdap] (Boostrix, GSK) today for immunization during the third trimester of pregnancy to prevent pertussis—or whooping cough—in infants under 2 months of age.
The approval was granted to GlaxoSmithKline Biologicals.
According to Peter Marks, MD, PhD, director of the FDA’s Center for Biologics Evaluation and Research, babies are at highest risk for getting pertussis and having serious related complications. This vaccine, tetanus toxoid, reduced diptheria toxoid and acellular pertussis vaccine, adsorbed [Tdap] (Boostrix) was first approved by the FDA in 2005 as a single dose for booster immunization against tetanus, diphtheria and pertussis in individuals aged 10 to 18. It was then also approved to include use in individuals aged 19 and older, and to include use of an additional dose 9 or more years after the initial dose of a Tdap vaccine. Apparently, the FDA’s approval has always included its use during pregnancy to protect the vaccinated individual. Today’s approval, however, specifically approves its use in pregnancy to prevent pertussis in infants under 2 years of age. Since 2012, the Centers for Disease Control and Prevention (CDC) have recommended the use of Tdap vaccines during the third trimester of pregnancy.
The safety of the vaccine during the third trimester of pregnancy was assessed in a randomized, placebo-controlled study with a non-US formulation. The FDA considered the safety data with the non-US formulation relevant because it contains the same components as the US formulation, except the non-US formulation contains more aluminum per dose. The study included 680 pregnant individuals, of whom 340 received the non-US formulation and of whom, 340 received saline placebo.
The rates of side effects were the same among both groups—during pregnancy and after childbirth. The study did not find any vaccine-related adverse effects on pregnancy or on the fetus.
The most common side effects in previous studies were pain, redness at injection site, headache, fatigue and gastrointestinal symptoms.
Office. FDA Approves Vaccine for Use During Third Trimester of Pregnancy to Prevent Whooping Cough in Infants Younger Than Two Months of Age. U.S. Food and Drug Administration. Published 2022. Accessed October 7, 2022. https://www.fda.gov/news-events/press-announcements/fda-approves-vaccine-use-during-third-trimester-pregnancy-prevent-whooping-cough-infants-younger-two