(HealthDay News) – Two doses of the four-component Neisseria meningitidis serogroup B (4CMenB) vaccine is highly immunogenic in adolescents, according to a study published online Jan. 18 in The Lancet.
María Elena Santolaya, MD, from Universidad de Chile in Santiago, and colleagues randomly assigned 1,631 adolescents (11–17 years old) to receive one, two, or three doses of 4CMenB at one-, two-, or six-month intervals. Immunogenicity against three of the strains was assessed as serum bactericidal activity using human complement (hSBA), and immunogenicity against the fourth strain was assessed by enzyme-linked immunosorbent assay. All participants received at least one dose of the vaccine.
The researchers found that 99–100% of recipients had hSBA titers of 4 or more against test stains after two or three doses, compared with 92–97% after one dose and 29–50% after placebo. At six months, titers were still 4 or more in 91–100% of subjects who received two or three doses, compared with only 73–76% after one dose. For each strain, at six months, seroresponse rates were 99–100% after the second or third dose.
“On the basis of immunogenicity responses, this study provides evidence for an adolescent 4CMenB vaccine schedule of two doses, one to six months apart, to provide protection against meningococcal B infection,” the authors write.
All of the authors disclosed financial ties to Novartis Vaccines and Diagnostics, which funded the study and manufactures 4CMenB vaccine.