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Pfizer Awarded Grant Supporting Study of Maternal Vaccine to Protect Against Group B Strep

There is an urgent global health need for a vaccine that could protect pregnant women and their infants against Group B Streptococcus (GBS) infection, a leading cause of a serious neonatal blood infection (sepsis[i]), pneumonia, and meningitis. In many cases, GBS bacteria are passed from mother to baby during labor and birth. Since newborns have immature immune systems that are still adapting to the environment outside the womb, the bacteria have the potential to cause life-threatening disease.

In the developed world, women who test positive for Group B strep bacteria are given intravenous antibiotics before delivery to prevent transmission to their babies. But developing countries often lack the healthcare infrastructure to follow these preventative measures. The mortality rates for neonatal GBS infections are around 6 percent to 14 percent of those infected in industrialized countries[ii] and approximately 14 percent to 38 percent of those infected in parts of the developing world.[iii]

In an effort to protect these newborns and their mothers, Pfizer has been awarded a grant from the Bill & Melinda Gates Foundation to support its Phase 1 / 2 clinical trial of Pfizer’s vaccine candidate against (GBS) infection. The investigational vaccine would protect newborns via maternal immunization.

“The health benefits of maternal immunization to protect pregnant mothers and their babies against flu, tetanus and pertussis are well-documented,” said Kathrin U. Jansen, Ph.D., Senior Vice President and Head of Vaccine Research & Development. “We are looking to demonstrate whether our investigational vaccine could generate levels of protective antibodies in the mother that, when passed to her unborn baby, will protect the baby against deadly GBS infection during a time when the infant is most vulnerable to infection.”

The start of human studies for the GBS investigational vaccine is the first in a series of vaccines candidates Pfizer plans to move into clinical trials to address important maternal and neonatal infections, such as respiratory syncytial virus (RSV) and cytomegalovirus (CMV), further expanding the company’s focus on maternal immunization in areas of unmet medical need.

Read the press release »


[i] Thigpen Michael C, et al. Bacterial Meningitis in the United States, 1998–2007. N Engl J Med. 2011: 364:2016-2025.

[ii] Edwards MS, Gonik B, “Preventing the broad spectrum of perinatal morbidity and mortality through group B streptococcal vaccination.” Accessed 24 June 2016. Available at

[iii] Johri AK, Lata H, et al., “Epidemiology of Group B Streptococcus in developing countries.” Accessed 24 June 2016. Available at

[iv] Le Doare and Heath 2013 (