Pfizer’s pneumococcal shot shows stronger immune response

Dubai: Pfizer said on Wednesday that its experimental pneumococcal vaccine demonstrated a significantly stronger immune response than its current shot, including up to 15-fold higher antibody levels against a key strain, in a mid-stage study.The vaccine maker tested its 25-valent vaccine, called 25vPnC, in healthy infants during the trial.Pneumococcal disease can cause infections in several parts of the body, including the lungs, increasing the risk of pneumonia.In the trial, the vaccine generated strong immune responses across all targeted strains and was well tolerated, with no safety concerns identified.Pfizer said that antibody levels in patients after the third dose of 25vPnC were about 8.8 times higher than those seen with its current vaccine, Prevnar 20, and about 15 times higher after the fourth dose.Prevnar 20 was first approved in the United States in 2021 to prevent pneumococcal disease in adults, with its use later expanded to infants and children in 2023.Pfizer noted that 25vPnC could potentially protect against about 90% of disease-causing strains in children under five, compared to current vaccines.According to the U.S. Centers for Disease Control and Prevention (CDC), children younger than five years and adults aged 50 or older are at higher risk of pneumococcal disease.Based on these results and discussions with regulators, Pfizer has initiated a late-stage trial involving up to 2,400 infants, comparing 25vPnC with Prevnar 20 in a four-dose schedule.Separately, Pfizer said it is advancing an adult pneumococcal vaccine candidate targeting 35 strains, with plans to begin clinical development by the end of 2026.