The meningitis B (MenB) vaccine Bexsoro turned out to be less than efficient, according to a study. The drug, which was administered during a MenB outbreak in Princeton University in 2013, triggered an immune response in most of the recipients, but failed in 34% who showed no response when the outbreak took place.
According to the University of Minnesota Center for Infectious Disease Research and Policy, researchers began administering Bexsoro, made by pharmaceutical giant GlaxoSmithKline, at Princeton in December 2013, when an outbreak began. At the time, the meningococcal serogroup B vaccine (4CMenB) was approved for use in Europe and Canada.
Six thousand Princeton students were offered the vaccine, and 89% of them received at least one dose within 2 months of the outbreak. When the outbreak ended after 2 years, 9 cases on MenB and 1 death had been reported on campus.
Nicole Basa, assistant professor of epidemiology and community health at the University of Minnesota, said that they were in the unique position to test the vaccine before it was approved in the USA. She said,
All students who were tested had an immune response to at least one strain contained in the vaccine, but a third didn’t have any response to the outbreak strain.
Basta and her team studied 499 students who had received two doses of the 4CMenB vaccine over a period of 10 weeks. Two months after the second vaccine dose was administered, only 66% of the participants showed bactericidal activity fighting the MenB strain that was plaguing the campus.
The study authors said that the level of ineffectivity the vaccine showed was lower than expected, “given that the Meningococcal Antigen Typing System predicted that 4CMenB would induce responses against the outbreak strain.”
The study concluded that a third dose of the vaccine might increase effectivity during an outbreak. In an accompanying editorial to the study, Jerome Kim, director general of the International Vaccine Institute, said that the 4CMenB vaccine could still be important for public health.
While rare, MenB infections can be fatal and have been known to wreak havoc on campuses. Since 2009, there have been seven college campus outbreaks, ending in 3 deaths and 43 infections. College students are at a higher risk due to close quarter living and sharing food and drinks.
Basta said that she still recommends the vaccine to teens and young adults. The Advisory Committee on Immunization Practices, which guides the Centers for Disease Control and Prevention, said that, “Vaccination of all adolescents would prevent 15 to 29 cases and 5 to 9 deaths annually in the United States.”
The study was published in the New England Journal of Medicine.
