FDA Delays Decision on Merck's Pediatric Pneumococcal Vaccine

 Merck announced Friday that the U.S. Food and Drug Administration extended the Prescription Drug User Fee Act date for its supplemental Biologics License Application (sBLA) for Vaxneuvance, a pneumococcal conjugate vaccine intended for preventative use in infants and children. The final decision on the vaccine is expected on July 1, 2022.

In December 2021, Merck announced that the FDA accepted the sBLA for Priority Review. It included data from Phase II and III clinical studies of the vaccine candidate's efficacy in a patient population aged six weeks to 17 years. 

The data supported the use of Vaxneuvance in a variety of clinical settings, including the immunization of infants and toddlers with increased risk for infection, such as those with sickle cell disease or human immunodeficiency virus (HIV) infection. The clinical trials also investigated the efficacy of using the pneumococcal conjugate in conjunction with PCV13, an existing pneumococcal vaccine for infants and children with lower valency.

Now, the FDA has extended its review of the vaccine candidate. The regulatory agency requested additional data analyses from the pediatric studies that Merck stated it has submitted. No new studies were requested by the FDA.

 "We are confident in the strength of the data from our pediatric studies with VAXNEUVANCE and will continue to work expeditiously with the FDA to bring this important vaccine forward to infants and children in the United States as soon as possible," said Dr. Eliav Barr, senior vice president, head of global clinical development and chief medical officer, Merck Research Laboratories.

Vaxneuvance received approval from the FDA in July 2021 for use in adults over the age of 18. The pneumococcal vaccine covers 15 different strains of the bacteria that cause pneumococcal disease, S. pneumoniae. Approval was based on seven clinical studies assessing safety, tolerability and immunogenicity in adults, with clinical data showing that the immune responses elicited by Vaxneuvance were non-inferior to the currently available PCV13, which covers 13 different strains of bacteria.

Additionally, Vaxneuvance was superior to PCV13 in immune responses to serotype 3, 22F and 33F, with 22F and 33F being unique to Vaxneuvance. The clinical results were similar to Merck's clinical studies evaluating the vaccine's efficacy in younger populations.

Pneumococcal disease presents a significant risk to children younger than two years old. Depending on the strain contracted, pneumococcal disease in children can cause a host of systemic disorders, including pneumonia, meningitis, middle ear infections and blood infection. Although infections with the bacteria may result in only mild illness, it can also spark very dangerous pathology that can lead to lifelong disabilities, including deafness, brain damage or loss of limbs.

Merck is up against several other biopharmaceutical companies hoping to edge into the pediatric market with pneumococcal conjugate vaccines. In June 2021, the FDA approved a new version of Pfizer's pneumococcal conjugate vaccine dubbed Prevnar 20, which delivers protection against 20 strains of bacteria in adults. Although no recent updates have been shared on clinical progress regarding Prevnar 20's efficacy in children, Pfizer's previous pneumococcal conjugate vaccine, Prevnar 13, is indicated for use in children.

Inventprise is also in the race to develop an effective pneumococcal conjugate vaccine with $90 million in funding from the Bill & Melinda Gates Foundation. IVT-25 boasts the broadest serotype coverage in development and is currently gearing up for Phase I and II clinical trials.      

https://www.biospace.com/article/fda-extends-date-for-approval-of-merck-s-pneumococcal-vaccine/