Immunogenicity and Safety of a Two-Dose Series of a Meningococcal (Groups A, C, W, and Y) Polysaccharide Diphtheria Toxoid Conjugate Vaccine (MEN ACWY-D) in Healthy Japanese Adults.

This study (NCT02591290) evaluated the safety and immunogenicity of two doses administered eight weeks apart to 60 healthy Japanese adults aged 20-55 years. Blood samples were collected 28-35 days after each vaccination. Immunogenicity endpoints included seroprotection and seroconversion rates. Safety assessments included systemic adverse events (AEs), non-serious AEs, and serious AEs. Fifty-eight (96.7%) participants completed the study. Seroprotection rates for serogroups A, C, W, and Y before vaccination were 76.8%, 26.8%, 26.8%, and 50.0%, increasing to 100%, 83.9%, 91.1%, and 96.4% and 100%, 92.9%, 94.6%, and 94.6%, respectively, after two doses. Seroconversion rates for the four serogroups were 100%, 93.8%, 97.1%, and 94.1% after the first dose and 100%, 96.9%, 100%, and 100% after the second. Increases between doses were insignificant. There were no safety concerns. The two-dose series is well tolerated but clinical benefit of a second dose within 8 weeks seemed to be low. PMID: 33132297 [PubMed - as supplied by publisher]
Source: Japanese Journal of Infectious Diseases - Category: Infectious Diseases Authors: Tags: Jpn J Infect Dis Source Type: research