New Meningitis Vaccine Works in Infants
TUESDAY Jan. 8, 2008 -- A new type of meningitis vaccine appears to offer protection for babies against several strains of the deadly bacterial form of the disease, British and Canadian researchers report.
The new vaccine, which is not yet licensed in the United States, provides immunity against four strains of meningococcal disease in all age groups, according to a study in the Jan. 9 issue of the Journal of the American Medical Association. There is currently no meningococcal vaccine approved for use in children under 2 in the United States.
"The key message for parents to take from this study is that this vaccine has the potential to reduce the number of cases of meningitis in babies and young children," said study author Dr. Matthew Snape, a pediatrician at the University of Oxford in the United Kingdom.
"There are approximately 1,400 to 2,800 cases of meningococcal infections in the United States per year. Approximately 10 to 14 percent of people experiencing this disease will die, and 20 percent of survivors will have long-term disabilities," said Snape. "The highest rates of disease are seen in children under the age of 2 years."
Meningitis is an infection that occurs in the spinal fluid, and it can be caused by a virus or bacterium, according to the U.S. Centers for Disease Control and Prevention. The bacterial forms of meningitis tend to be more serious, potentially causing brain damage, hearing loss and learning disabilities. Two vaccines -- the Haemophilus influenza (Hib) and pneumococcal -- can protect youngsters, including babies, against certain strains of bacterial meningitis, but not all. Two other vaccines offer protection against four strains of the Neisseria meningitidis bacteria -- one for children aged 2 to 10 and the other for those aged 11 and up -- but neither offers protection to babies.
The latest vaccine, produced by Novartis, offers protection against four serotypes of meningococcal disease: groups A, C, W-135 and Y, according to Snape. The current study was designed to assess the new vaccine's effectiveness and safety in infants.
The British and Canadian researchers recruited a total of 421 2-month-old infants for the phase II randomized, controlled trial. The 225 British infants received the new vaccine, called Menveo, at 2, 3 and 4 months or at 2 and 4 months of age, or they were given one of the current N. meningitides vaccines at 2 and 4 months, and then all received the new vaccine at 12 months. The 196 Canadian babies were given the new vaccine at 2, 4 and 6 months or at 2 and 4 months, and then at 12 months, they were either given another shot of the new vaccine, a shot of one of the current vaccines, or no vaccine at all, according to the study.
"The study showed that the [Menveo] vaccine was able to stimulate production of protective antibodies against all four meningococcal groups in most of the children receiving the vaccine," said Snape. "For example, for children receiving the vaccine at 2, 3, 4 and 12 months of age, protective antibody levels were seen in 94 percent or above for all the meningococcus types."
Additionally, Snape said the vaccine was well-tolerated, and there were no serious adverse events related to the vaccine. He also noted that the vaccine doesn't contain the controversial preservative, thimerosal.
"This is a potentially huge advance for the prevention of meningococcal disease," said the author of an accompanying editorial in the same issue of the journal, Dr. Lee Harrison, a professor of medicine and epidemiology at the University of Pittsburgh. "This vaccine is looking very promising."
Novartis is currently conducting phase III clinical trials on the vaccine and hopes to begin the licensing procedure in the United States sometime in 2008, though it would still be a few more years before any vaccine would be commercially available in this country.
In the meantime, Harrison pointed out, "Parents should also know that there are already two vaccines to help prevent meningitis for infants -- the group at highest risk -- Hib and pneumococcal vaccine. The new vaccine would just be the third piece of the puzzle."
For parents with older children, Harrison said there's already a "very good vaccine" available for 11- to 18-year olds to prevent meningitis.
To learn more about meningococcal disease, visit the U.S. Centers for Disease Control and Prevention.
Posted: January 2008