Group B streptococcus vaccine candidate wins regulatory traction

FDA has granted Pfizer’s (NYSE:PFE) investigational Group B Streptococcus (GBS) vaccine candidate, GBS6 or PF-06760805, Breakthrough Therapy Designation.

The designation covers active immunization of mothers during pregnancy to confer protection against invasive GBS disease in newborns and young infants.

GBS disease can result in lifelong neurologic impairments or death, according to a 2019 article in the Journal of Infectious Diseases.

The six most common GBS serotypes cause approximately 98% of GBS disease globally.

Group B streptococcus has been the most common cause of sepsis in newborns since the 1970s, according to the CDC.

The incidence of group B streptococcus has also risen in nonpregnant adults in recent decades, according to a 2019 study published in JAMA. In adults, chronic conditions such as obesity and diabetes may be associated with an elevated risk of contracting GBS.

The FDA’s recent decision is based on data from an interim analysis of a placebo-controlled Phase 2 study (NCT03765073) testing GBS6 in healthy pregnant women between 18 and 40. The women in the study received the vaccine in the second or early third trimester.

The ongoing observer-blinded NCT03765073 study has approximately 586 subjects.

Treatment options to reduce the risk of GBS include prenatal screening and antibiotics during childbirth.

Those options, however, are not fully protective in the first week of life and can be challenging in low- and middle-income countries, according to Annaliesa Anderson, senior vice president and head of vaccine research and development at Pfizer. Additionally, current treatments have “not been shown effective in preventing disease globally in infants beyond the first week of life and through the vulnerable first three months of life,” said Anderson in a news release.

Pfizer anticipates that GBS6, if approved, could help reduce the risk of GBS-related conditions such as meningitis, pneumonia and sepsis.

GBS6 is a hexavalent capsular polysaccharide conjugate vaccine.

PFE shares ticked up 0.81% to $46.13 today.

FDA created the Breakthrough Therapy Designation to accelerate the development and review of therapies that can treat or prevent serious conditions. In awarding the designation, the agency looks for data suggesting that an investigational therapy could lead to substantial improvement in at least one clinically significant endpoint over currently available treatment options.