The FDA has granted Pfizer’s investigational vaccine RSVpreF a Breakthrough Therapy designation for the prevention of respiratory syncytial virus-related (RSV) lower respiratory tract disease in patients 60 years or older.

The breakthrough designation was based in part on positive results from a phase 2a trial of the RSVpreF vaccine in healthy adults ages 18 to 50. Pfizer has not publicly released data from the trial. A phase 3 trial in patients 60 years or older that began in September 2021 is still ongoing.

The RSVpreF vaccine has also received a Breakthrough Therapy designation from the FDA for the prevention of RSV-related lower respiratory tract disease in infants from birth to 6 months old through immunization of pregnant women.