More Meningitis Protection on the Way

Bacterial meningitis vaccine to protect against more strains is safe and effective

(RxWiki News) The tricky thing about protecting people against bacterial meningitis is that so many different strains exist and the current vaccines protects against only a couple.

A couple vaccines exist for specific strains of meningococcal serogroup B, which causes bacterial meningitis, but a vaccine that protects against this whole class of strains is not yet available.

The conclusion of a recent trial for a vaccine that would protect people against a wide range of bacterial meningitis strains showed both good levels of effectiveness and a good safety record.

"Be sure you're up to date on all your immunizations."

Peter Richmond, of the University of Western Australia School of Paediatrics and Child Health, led the study to test the safety and effectiveness of a vaccine to protect against the majority of serogroup B strains.

A total of 539 healthy adolescents were enrolled from 25 sites in Australia, Poland and Spain, and 511 received all three vaccinations (including the boosters).

Anyone who had already had meningitis or a vaccine for it were excluded as well as anyone who had had a previous adverse reaction to a vaccine or had a health condition that would make it possibly unsafe to vaccinate them, such as taking immunosuppressive therapy.

The placebo vaccine - which did not contain a meningococcal immunization - was given to 116 participants. The others received one of three different doses: 21 participants received a 60 μg (micrograms) dose; 191 received a 120 μg dose; and 183 received a 200 μg dose.

After receiving the first immunization, participants received booster shots two months later and six months later. The researchers then tested their immune response with a "titre" measurement.

The majority (80 to 100 percent across both strain groups tested) of the adolescents' immune systems created antibodies following the round of immunizations that protected them against 90 percent of the invasive meningococcus serogroup B strains that exist in the U.S. and Europe.

Those receiving the 120 and 200 μg doses had similar titre readings, and effectiveness for two sets of the strains tested ranged in the 80th to 90th percentiles across the various doses. Five people placebo group people had high immunity levels for one of the strains.

"Our data suggest that this vaccine is a promising and broadly protective meningococcal serogroup B vaccine candidate," Richmond said. "If additional studies show similar immunogenicity and tolerability, this vaccine might help to reduce the global burden of invasive meningococcal disease."

The most common side effect was mild to moderate pain at the injection site, which occurred for 1,005 shots out of the total 1,533 shots given.

Other side effects that occurred included fatigue or headache, which occurred for 241 of the participants, and a mild fever that occurred after 65 shots, including 5 placebos. One serious adverse event occurred during the trial after the third shot but the participant had a full recovery.

The study appeared online in the Lancet Infectious Diseases May 6. The research was funded by Wyeth and Pfizer, both pharmaceutical companies that manufacture vaccines.

As with most researchers who study or test vaccines, the majority of authors have a range of ties to pharmaceutical companies including GlaxoSmithKline, Merck, Novartis, Sanofi Pasteur, Wyeth and Pfizer. The ties include honorariums for speeches, travel support, participation in leading other clinical trials, consultant fees and participation on advisory boards.

Review Date: 
May 5, 2012