Tag: Group B streptococcus

Categories : Obstetrics & Gynaecology VaccinesTags :

Wits VIDA Globally Advances Maternal Vaccine to Protect Newborns from GBS

On By ModernMedia

Wits VIDA plays central role in global effort to help protect newborns from sepsis due to Group B Streptococcus (GBS).

Photo by ManuelTheLensman on Unsplash

Researchers from the Wits Vaccines and Infectious Diseases Analytics (Wits VIDA) Research Unit at the University of the Witwatersrand (Wits) have played a leading role in a landmark international phase 1 / 2 clinical trial demonstrating the safety and immunogenicity of an investigational maternal vaccine against Group B Streptococcus (GBS) – a major cause of life-threatening infections in newborn babies worldwide. The findings have been published in Nature Medicine.

The study evaluated Pfizer’s investigational hexavalent Group B Streptococcus conjugate vaccine candidate (GBS6) in both non-pregnant women and pregnant women, together with their infants. The trial found that the vaccine was generally well tolerated, generated robust immune responses against all six clinically important GBS serotypes, and resulted in efficient transfer of GBS-specific antibodies from vaccinated mothers to their babies.

Wits VIDA was central to the implementation and successful conduct of the clinical trial. South Africa was the primary recruiting country, contributing the overwhelming majority of study participants across both the early and later stages of the trial, reflecting the country’s internationally recognised expertise in maternal and infant vaccine research.

Group B Streptococcus is one of the leading causes of neonatal sepsis, meningitis and pneumonia, accounting for approximately 300 000 serious infections, including 100 000 deaths, in young infants globally each year. The greatest burden of GBS disease in infants occurs in Africa and other low- and middle-income countries, with South Africa reporting among the highest incidence globally (approximately 2-3 cases for every 1000 births). Also, maternal GBS infection could predispose to preterm labour and stillbirths.  Current prevention strategies based on intrapartum antibiotics have important limitations, particularly in resource-constrained settings, and do not protect against late-onset disease. Consequently, the WHO has designated a vaccine against GBS, to be given to women during pregnancy aimed at protecting their young infant, as a priority vaccine for development.

Professor Shabir Madhi, Director of Wits VIDA and one of the study’s senior investigators, said: “This publication represents another important milestone in the decades-long effort to develop an effective maternal vaccine against Group B Streptococcus. Maternal immunisation offers the opportunity to protect newborns during the most vulnerable first months of life, when they are at greatest risk of severe infection. These encouraging findings provide further evidence supporting continued development of this vaccine.”

The trial demonstrated comparable safety outcomes between vaccine and placebo recipients. Among pregnant participants, rates of adverse events, serious adverse events and delivery outcomes were similar between the two groups. Infants born to vaccinated mothers likewise had similar safety outcomes to those born to mothers receiving placebo. Importantly, vaccinated mothers developed high concentrations of antibodies that crossed the placenta efficiently, resulting in robust antibody levels in their infants at birth.

The publication builds on Wits VIDA’s longstanding leadership in vaccine research, which has contributed to the development and evaluation of vaccines against respiratory syncytial virus (RSV), rotavirus, pneumococcal disease, influenza virus, COVID-19 and now Group B Streptococcus. The unit continues to play a pivotal role in generating evidence that informs global maternal and child health policy.

The study also highlights the importance of South Africa’s clinical research infrastructure and its contribution to advancing vaccines designed to address diseases that disproportionately affect African populations.

While additional studies are required before the vaccine can be licensed, the results provide strong support for continued clinical development of maternal GBS vaccination as a strategy to reduce newborn deaths and severe infections worldwide.

Wits is currently enrolling in a phase 3 trial for GBS6 (NCT: NCT07160244).

About Wits VIDA

The Vaccines and Infectious Diseases Analytics (VIDA) Research Unit at the University of the Witwatersrand is one of the world’s leading centres for vaccine and infectious disease research. VIDA conducts internationally recognised clinical trials, epidemiological studies and translational research focused on reducing the burden of infectious diseases, particularly among mothers, infants and children in Africa. Its research has contributed to the development and implementation of several life-saving vaccines globally.

Categories : VaccinesTags :

UN Urges Group B Streptococcus Vaccine to Protect Babies

On By ModernMedia
Photo by William-Fortunato on Pexels

There is an urgent need for vaccines against Group B streptococcus, a major cause of preterm births, disability and infant mortality worldwide, according to a UN-backed report published on Wednesday.

Group B streptococcus (GBS) is a gram-positive bacteria that colonises the gastrointestinal and genitourinary tract. It can be transmitted in utero, is linked to around 150 000 infant deaths each year, more than half a million preterm births and significant long-term disability.

The report by the World Health Organization (WHO) and the London School of Hygiene & Tropical Medicine (LSHTM) updates 2017 estimates, and reveals that the global burden of GBS is far higher than was previously recognised.

“This new research shows that Group B strep is a major and underappreciated threat to newborn survival and wellbeing, bringing devastating impacts for so many families globally,” said Dr Phillipp Lambach, Medical Officer from WHO’s Immunization, Vaccines and Biologicals department.

The report is the first to quantify the major contribution of GBS to preterm births, and to neurological impairments such as cerebral palsy, hearing and vision loss, that can occur following infection.

Around 15% of all pregnant women worldwide, nearly 20 million annually, carry the GBS bacterium in their vagina, which can then spread to a foetus, or to newborns during labour. At present, GBS disease prevention in newborns is by administering antibiotic prophylaxis to women during labour, if the bacterium is detected during pregnancy.

However, significant health risks remain, as this intervention is unlikely to prevent most GBS-associated stillbirths, preterm births, or GBS disease that occurs later after birth.

“It is difficult to describe the breadth or depth of the grief when your child dies, or the accompanying guilt, and how it changes you, your family, and your relationships forever,” said Debbie Forwood, whose daughter Ada was stillborn after she developed a GBS infection.

Vaccine development urged
GBS burden is highest in low and middle-income countries, where screening and treatment are most challenging to implement, with regions such as sub-Saharan Africa having the highest rates of maternal GBS.
Now is the time for action, said Joy Lawn, an LSHTM Professor who contributed to the report.  While several candidate GBS vaccines are in development, none are yet available despite decades in the pipeline. The report calls for stepping up development of an effective GBS vaccine that could be administered to expectant mothers during routine pregnancy checkups.

The partners estimate more than 50 000 GBS-related deaths, and over 170 000 pre-term births, could be avoided if over 70 per cent of pregnant women were vaccinated.

Such protection could also be highly cost-effective, they added.  Net benefits from a year of maternal vaccinations could reach as high as $17 billion, accruing over several years, provided doses are affordably priced. For Ms. Forwood, this would be a bittersweet development.

“Only a GBS vaccine could have saved Ada.  When a vaccine can be widely rolled out, I will weep and scream with the unfairness that it came too late for her, and for all the other babies who are needlessly suffering and dying every year that it is delayed,” she said.

“But I will also weep with joy that in the future, many more will live, and their families will be saved from the living hell that is the death of a child.”

Source: UN News