Infant Vaccine Against Meningitis Shows Promise

Jan. 9, 2008— -- An experimental vaccine appears to protect newborns from meningococcal disease, a major cause of meningitis.

Babies under 1 year are especially vulnerable to meningococcal disease. Infants this age have the highest rates of infection but aren't protected by an existing vaccine, which is approved only for children over 2.

Though this type of meningitis is relatively rare -- it afflicts only 1,400 to 2,800 Americans a year -- it can be devastating. Ten percent to 14 percent of patients die, and up to 20 percent of survivors develop long-term disabilities, such as brain damage, hearing loss or amputation, according to a study in today's Journal of the American Medical Association.

"It's one of the few infections left in the U.S. that can kill a healthy young person in only a couple of hours," says Lee Harrison, a professor of medicine and epidemiology at the University of Pittsburgh, who wrote an editorial accompanying the study.

Doctors hope an experimental shot from Novartis, called Menveo, will prevent much of that suffering. Researchers in Canada and the United Kingdom tested Menveo -- which targets four of five meningococcal bacteria strains -- in more than 400 babies, the study said. The study received funding from Novartis.

Babies need several doses of Menveo for long-term immunity. The vaccine was about 94 percent effective when given in four doses, one at 2 months, 3 months, 4 months and 12 months -- a dosing schedule that fits into standard vaccination programs in the U.K., says study author Matthew Snape, a pediatrician at the University of Oxford.

When given in three doses, one each at 2 months, 4 months and 12 months -- the standard pattern for shots in the USA -- the vaccine was 86 to 100 percent effective, providing more protection against some strains of the bacteria than others, Snape says.

If approved, a meningococcal vaccine could prevent half of the roughly 300 cases of meningococcal meningitis in babies under 2, says Amanda Cohn, a pediatrician at the Centers for Disease Control and Prevention.

Vaccines have made tremendous strides toward eliminating meningitis in recent years. They have reduced the number of meningitis cases by more than 95 percent, Cohn says.

Meningitis cases in children under 2 fell from about 20,000 a year to roughly 1,500 after the introduction of a vaccine against the bacteria Haemophilus influenzae type b, or Hib, in 1990. Prevnar, a vaccine approved in 2000 that targets the meningitis-causing pneumococcus bacteria, has further reduced illness from the disease, Harrison says.

A meningococcal vaccine "is the next phase of eliminating meningitis in young children," Cohn says. Harrison notes, however, that Menveo needs to be tested in larger studies. Novartis, which has applied for Food and Drug Administration approval, already is conducting broader trials, company spokeswoman Beth Birke says.