Pfizer will submit an application to the Food and Drug Administration later this year to expand approval of its new pneumococcal vaccine after reporting positive results from a Phase 3 trial.
Pfizer already has a pneumococcal vaccine called Prevnar 13, which is one of the company’s top-selling products and has been widely used for years. However, the vaccine only covers 13 strains of the bacteria that causes pneumococcal disease. Pfizer’s newest shot, sold as Prevnar 20, covers 20 strains and was approved by the FDA in 2021 for use in adults over the age of 18.
The latest trial is one of several studies designed to prove the vaccine can work just as well in younger children and infants.
The study sought to show the immune responses generated one month after the third and fourth doses of the 20-strain vaccine were not worse than that of Prevnar 13. Researchers found that immune responses met that bar against all 20 strains following the fourth dose. After the third dose, immune responses were “non-inferior” against 14 strains, with results for four strains narrowly missing the study’s success criteria and more widely for two others. Safety results were similar to that of Prevnar 13, Pfizer said.
Based on the results, Pfizer will submit a supplemental approval application before the end of the year. Data from other studies in children are expected later in the year as well.
In the market for pneumococcal vaccines, Pfizer has long competed with Merck & Co., which sold Pneumovax 23. In July 2021, Merck won FDA approval for its own second-generation shot, called Vaxneuvance. The vaccine covers 15 strains and has not yet been tested head to head against Prevnar20.
Earlier this year, Merck got a step ahead of Pfizer in the pediatric population, winning FDA approval of Vaxneuvance for infants and children aged 6 weeks through 17 years.
Both of the new vaccines have been recommended for use by advisers to the Centers for Disease Control and Prevention.
The large market has drawn interest from other vaccine makers. Just recently, in May, GSK paid $2.1 billion to acquire private company Affinivax, which is developing another pneumococcal vaccine.