The immunogenicity and safety of a tetravalent measles-mumps-rubella-varicella vaccine when co-administered with conjugated meningococcal C vaccine to healthy children: A phase IIIb, randomized, multi-center study in Italy ☆

•Open, randomized, phase IIIb study conducted at 13 centers in Italy.•MMRV+MenC vaccine seroconversion rates non-inferior to separate MMRV/MenC vaccines.•MenC vaccine did not alter the safety profile of MMRV vaccine administered alone.•Co-administered MMRV and MenC vaccines could reduce number of clinic visits.