The investigational quadrivalent conjugated vaccine MenACWY-CRM (Menveo™) is well tolerated and immunogenic in infants as young as six months of age, protecting against four common serogroups of meningococcal meningitis, according to phase II data reported at the 5th World Congress of the World Society for Pediatric Infectious Diseases (WSPID).

Although meningococcal meningitis primarily affects young children and most often during the first three to 12 months of life, there is currently no effective vaccine with broad serogroup coverage for this high-risk age group. Available licensed quadrivalent polysaccharide vaccines against serogroups A, C, Y and W-135 do not confer long-term protection and are poorly immunogenic in children less than two years of age. A conjugate vaccine approved for use in infants is only available against the C serogroup. Due to changing epidemiology of the disease, there is a growing need to vaccinate all age groups against as many serogroups as possible.

The study, led by Scott A. Halperin, MD, Director of the Canadian Center for Vaccinology at Dalhousie University in Halifax, Canada, confirms data presented in 2006 but uses an alternative dosing schedule.

For the trial, 175 infants received either two doses of MenACWY-CRM at six and 12 months, one dose at 12 months, or meningococcal C conjugate vaccine (MenC, MenjugateR) at 12 months and MenACWY-CRM at 18 months of age.

After two doses of MenACWY-CRM, the percentage of infants who achieved human (complement) serum bactericidal assay (hSBA) titer ≥1:4 was 100% for serogroups C, W-135, and Y, and 86% for A. High levels of immune response were also seen in the group who received one dose.

Serogroup C geometric mean titers (GMTs) were ten-fold higher after two doses of MenACWY-CRM than MenC vaccination at 12 months and comparable after single doses of MenACWY-CRM or MenC at 12 months.

All vaccines were well tolerated, and local and systemic reactions were similar between vaccination groups.

“These data are encouraging given the unmet need for an effective meningococcal meningitis vaccine with broad serogroup coverage that can be given to infants,” said Dr. Halperin.

The study was conducted at three sites in Canada.

MenACWY-CRM is being developed by Novartis Vaccines to protect individuals from infancy through adulthood as well as high-risk groups against four of the five disease-causing serogroups of the bacterium: A, C, Y and W-135. Novartis is also developing a recombinant vaccine aimed at providing coverage against the B serogroup, a target that has remained elusive until now.

A company spokesperson said that MenACWY-CRM is the first quadrivalent meningitis vaccine to demonstrate an excellent immune response in infants. Several phase III trials of MenACWY-CRM are presently underway involving infants, young children, adolescents, and adults.

Meningococcal meningitis is a potentially fatal bacterial infection that can also lead to permanent disability. Approximately 500,000 cases occur annually worldwide, resulting in about 50,000 deaths each year.

http://www.novartisvaccines.com

By Jill Stein
Jill Stein is a freelance medical writer, based in Paris
Jillstein03 at cs.com (at replaces @ to protect from spammers)