Pneumonia is still the leading cause of death among African children with pneumococcal serotypes 1 and 5 being dominant in the below 5 y of age group. The present study assessed the safety, reactogenicity and immunogenicity of a 2-dose catch-up vaccination with the 10-valent pneumococcal non-typeable Haemophilus influenzae Protein D conjugate vaccine (PHiD-CV) in Malian children. This phase III, open-label study (NCT00985465) was conducted in Ouelessebougou, Mali, between November 2009 and July 2010. The study population consisted of PHiD-CV unprimed Malian children previously enrolled in the control group of study NCT00678301 receiving a 2-dose catch-up vaccination with PHiD-CV in the second year of life. Adverse events were recorded following each PHiD-CV dose. Antibody responses and opsonophagocytic activity (OPA) were measured pre-vaccination and after the second PHiD-CV catch-up dose. Swelling and fever (axillary temperature ≥ 37.5°C) were the most frequently reported solicited symptoms following either PHiD-CV dose. Few grade 3 solicited symptoms were reported. Large swelling reactions and serious adverse events were not reported. Post-catch-up vaccination, for each vaccine pneumococcal serotype, at least 94.7% of subjects had antibody concentrations ≥ 0.2 μg/ml, except for serotypes 6B (82.5%) and 23F (87.7%). At least 94.0% of subjects had OPA titres ≥ 8, except for serotype 19F (89.4%). The geometric mean concentration for antibodies against protein D was 839.3 (95% CI: 643.5-1094.6) EL.U/ml. Two-dose PHiD-CV catch-up regimen in the second year of life was well-tolerated and immunogenic for all vaccine pneumococcal serotypes and NTHi protein D when administered to Malian children.
Keywords: 22F-ELISA, 22F-inhibition enzyme-linked immunosorbent assay; 7vCRM, 7-valent pneumococcal CRM197 conjugate vaccine; AE, adverse event; ATP, according-to-protocol; CI, confidence interval; DTPw-HBV/Hib, diphtheria-tetanus-whole-cell pertussis, hepatitis B virus/Haemophilus influenzae type b vaccine; EL.U, ELISA unit; GAVI, Global Alliance for Vaccines and Immunization; GMC, geometric mean concentration; GMT, geometric mean titer; IPD, invasive pneumococcal disease; IgG, immunoglobulin G; LAR, legally acceptable representative; Mali; NTHi, non-typeable Haemophilus influenzae; OPA, opsonophagocytic activity; OPV, oral live attenuated poliovirus vaccine; PCV, pneumococcal conjugate vaccine; PHiD-CV; PHiD-CV, pneumococcal non-typeable Haemophilus influenzae (NTHi) protein D conjugate vaccine; SAE, serious adverse event; SD, standard deviation; catch-up vaccination; immunogenicity; pneumococcal conjugate vaccine; reactogenicity; safety.