Safety and immunogenicity of concureent administration of live attenuated influenza vaccine with measles-mumps-rubella and varicella vaccines to infants 12 to 15 months of age

Objective. This study evaluated the safety, tolerability, and immunogenieity of live attenuated influenza vaccine administered concurrently with measles-mumps-rubella vaccine and varicella vaccine to healthy children 12 to 15 months of age. Methods. Children were assigned randomly to receive (1) measles-mumps-rubella vaccine, varicella vaccine, and intranasal placebo on day 0, followed by 1 dose of live attenuated influenza vaccine on days 42 and 72; (2) measles-mumps-rubella, varicella, and live attenuated influenza vaccines on day 0, followed by a second dose of live attenuated influenza vaccine on day 42 and intranasally administered placebo on day 72; or (3) 1 dose of live attenuated influenza vaccine on days 0 and 42, followed by measles-mumps-rubella and varicella vaccines on day 72. Serum samples were collected before vaccination on days 0, 42, and 72. Reactogenicity events and adverse events were collected through day 41 after concurrent vaccinations and through day 10 after administration of live attenuated influenza vaccine or placebo alone. Results. Among 1245 (99.5%) evaluable children, seroresponse rates and geometric mean titers for measles-mumps-rubella vaccine and varicella vaccine were similar with concurrent administration of live attenuated influenza vaccine or placebo (seroresponse rates of ≥96% for measles-mumps-rubella vaccine and ≥82% for varicella vaccine in both groups). Hem- agglutinin-inhlbiting antibody geometric mean titers and seroconversion rates to influenza strains in live attenuated influenza virus vaccine were similar after the vaccine was administered alone (seroconversion rates of 98%, 92%, and 44% for H3, B, and HI strains, respectively) or with measles-mumps-rubella and varicella vaccines (seroconversion rates of 98%, 96%, and 43%). The incidences of reactogenicity events and adverse events were similar among treatment groups. Conclusions. Concurrent administration of live attenuated influenza vaccine with measles-mumps-rubella vaccine and varicella vaccine provided equivalent immunogenieity, compared with separate administration, and was well tolerated.