A Phase III, Multicenter, Randomized, Double-Blind, Active Comparator- Controlled Study to Evaluate the Safety, Tolerability, and Immunogenicity of Catch-Up Vaccination Regimens of V114, a 15-Valent Pneumococcal Conjugate Vaccine, in Healthy Infants, Children, and Adolescents (PNEU-PLAN)

Background: Despite widespread use of pneumococcal conjugate vaccines (PCVs) in children, morbidity and mortality caused by pneumococcal disease (PD) remain high. In addition, many children do not com-plete their PCV course on schedule. V114 is a 15-valent PCV that contains two epidemiologically impor-tant serotypes, 22F and 33F, in addition to the 13 serotypes present in PCV13, the licensed 13-valent PCV.Methods: This phase III descriptive study evaluated safety and immunogenicity of catch-up vaccination with V114 or PCV13 in healthy children 7 months-17 years of age who were either pneumococcal vaccine-naive or previously immunized with lower valency PCVs (NCT03885934). Overall, 606 healthy children were randomized to receive V114 (n = 303) or PCV13 (n = 303) via age-appropriate catch-up vac-cination schedules in three age cohorts (7-11 months, 12-23 months, or 2-17 years).Results: Similar proportions of children 7-11 months and 2-17 years of age reported adverse events (AEs) in the V114 and PCV13 groups. A numerically greater proportion of children 12-23 months of age reported AEs in the V114 group (79.0%) than the PCV13 group (59.4%). The proportions of children who reported serious AEs varied between different age cohorts but were generally comparable between vaccination groups. No vaccine-related serious AEs were reported, and no deaths occurred. At 30 days after the last PCV dose, serotype-specific immunoglobulin G geometric mean concentrations were com-parable between vaccination groups for the 13 shared serotypes and higher in the V114 group for 22F and 33F.Conclusions: Catch-up vaccination with V114 in healthy individuals 7 months-17 years of age was gen-erally well tolerated and immunogenic for all 15 serotypes, including those not contained in PCV13, regardless of prior pneumococcal vaccination. These results support V114 catch-up vaccination in chil-dren with incomplete or no PCV immunization per the recommended schedule. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).