Immunogenicity and Safety of Two Tetravalent (Measles, Mumps, Rubella, Varicella) Vaccines Coadministered with Hepatitis A and Pneumococcal Conjugate Vaccines to Children Twelve to Fourteen Months of Age

Background: This study compared single-dose tetravalent measles, mumps, rubella, varicella vaccine, Priorix-Tetra, stored refrigerated (GSK+4C) or frozen (GSK-20C), with ProQuad (Merck-20C), when coadministered with hepatitis A vaccine (HAV) and 7-valent pneumococcal conjugate vaccine (PCV7). Methods: Multicenter, observer-blind phase 2 study in 1783 healthy 12-14 month olds randomized to: GSK+4C (n = 705), GSK-20C (n = 689) or Merck-20C (n = 389), administered concomitantly with HAV (Havrix) and PCV7 (Prevnar). Seroresponse rates and antibody geometric mean concentrations/titers were determined from enzyme-linked immunosorbent assay and neutralization assays. Reactogenicity and safety were assessed. Results: Seroresponse rates (day 42) were >97% for measles and rubella viruses and >92% for mumps virus, in all groups. Noninferiority of both GSK+4C and GSK-20C vaccines versus Merck-20C was demonstrated for seroresponse rates to measles, mumps and rubella viruses (lower 97.5% confidence interval above-5%,-10% and-5%, respectively). For varicella-zoster virus, seroresponse rates were 57.1%, 69.8% and 86.7% in the GSK+4C, GSK-20C and Merck-20C groups, respectively. Noninferiority was not shown for either GSK vaccine (lower 97.5% confidence intervals