NEW YORK (Reuters Health) – A vaccine against Haemophilus influenzae and Neisseria meningitidis given to infants during their first year has an acceptable safety profile and induces protective antibody levels, according to a report in the June issue of Pediatrics.

The incidence of meningococcal disease is highest in children younger than 2 years of age, but at the time of the current study there was no US-licensed vaccine for use in this age group, note Dr. Kristina A. Bryant, with the University of Louisville, Kentucky and colleagues.

Following successful phase II studies, the authors conducted a phase III randomized trial of the combined H. influenzae type b (Hib) and N. meningitidis serogroups C (MenC) and Y (MenY)-tetanus toxoid conjugate vaccine (HibMenCY) in 4180 infants in the US, Australia and Mexico.

The infants were assigned to receive either HibMenCY at the ages of 2, 4, 6 and 12-15 months, or a licensed Hib vaccine (ActHIB) at 2, 4, and 6 months and at 12-15 months a dose of PedvaxHIB (Hib conjugated to N meningitidis outer membrane protein). Other routine childhood vaccines were given at the same times.

After the fourth dose of the HibMenCY vaccine, over 98% of recipients had bactericidal levels of antibodies against N meningitidis serogroups C and Y, the investigators report.

Furthermore, Hib antibody response rates were similar in the HibMenCY group (96.3%) and the control group (91.2%) after the third dose.

After each dose, no more than 0.2% of infants in either group had fever higher than 40.0 centigrade, and large injection-site swelling was reported by just 0.4% with HibMenCY and 0.6% with the control vaccine, according to the report.

“This phase III study of HibMenCY reached noninferiority criteria in terms of immune responses to licensed monovalent Hib vaccines and showed robust immunogenicity of the MenC and MenY antigens and an acceptable safety profile,” Dr. Bryant and colleagues conclude.

They add, “HibMenCY has the potential to provide protection against serogroup-specific meningococcal disease without increasing shot burden in the infant immunization schedule.”

A disclosure statement notes that GlaxoSmithKline was the funding source and was involved in all stages of the study. Five of the 12 authors are employed by GSK.

Reference:
Immunogenicity and Safety of H influenzae Type b–N meningitidis C/Y Conjugate Vaccine in Infants
Pediatrics 2011;127:e1375–e1385.