title: Immunogenicity and safety of combined measles-mumps-rubella-varicella vaccine using new measles and rubella working seeds in healthy children in Taiwan and Singapore: a phase II, randomized, double-blind trial.
abstract: OBJECTIVE
  This study evaluated the immunogenicity and safety of tetravalent measles-mumps-rubella-varicella (MMRV) vaccine produced with measles and rubella monovalent bulks derived from a newly established working seed virus stock (MMRV(new WS)) compared with the combined MMRV vaccine derived from the current seed virus stock, in Taiwanese and Singaporean children (NCT00892775).
  
  
  METHODS
  Healthy children aged 11-22 mo were randomized to receive two doses of either the MMRV(new WS) vaccine or the MMRV vaccine. Antibody titers against measles, mumps and rubella were measured using ELISA and against varicella using an immunofluorescence assay. The primary objective was to demonstrate non-inferiority of MMRV(new WS) to MMRV in terms of post-dose-1 seroconversion rates, defined as a group difference with a lower limit of the 95% confidence interval greater than -10% for each antigen. Parents/guardians recorded symptoms in diary cards for 43 d after each vaccine dose.
  
  
  RESULTS
  Non-inferiority of MMRV(new WS) to MMRV was achieved for all vaccine antigens. The lower limits of the 95% confidence intervals for group differences (MMRV(new WS) group vs. MMRV) for measles (99.4% vs 100%), mumps (89.7% vs 90.4%), rubella (99.7% vs 100%) and varicella (97.6% vs 92.9%) seroconversion rates were greater than -10%. Mild symptoms including a peak in fever between days 5 and 12, post-dose-1, was observed in both groups.
  
  
  CONCLUSIONS
  The immune responses elicited by the MMRV(new WS) vaccine were non-inferior to that elicited by the MMRV vaccine for all antigens. Both vaccines exhibited an acceptable safety profile in Taiwanese and Singaporean children.
authors: Department of Pediatrics; National Taiwan University Hospital; Taipei, Taiwan.
authors: Li-Min
authors: LM
authors: Huang
authors: Bee-Wah
authors: BW
authors: Lee
authors: Poh Chong
authors: PC
authors: Chan
authors: Michael
authors: M
authors: Povey
authors: Ouzama
authors: O
authors: Henry
mesh_terms: D000914:Antibodies, Viral / Q000097:blood; D019433:Chickenpox Vaccine / Q000008:administration & dosage / Q000009:adverse effects* / Q000276:immunology*; D004311:Double-Blind Method; D064420:Drug-Related Side Effects and Adverse Reactions / Q000453:epidemiology / Q000473:pathology; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005334:Fever / Q000139:chemically induced; D005455:Fluorescent Antibody Technique; D064368:Healthy Volunteers; D006801:Humans; D007223:Infant; D008297:Male; D022542:Measles-Mumps-Rubella Vaccine / Q000008:administration & dosage / Q000009:adverse effects* / Q000276:immunology*; D012846:Singapore; D013624:Taiwan; D014611:Vaccination / Q000009:adverse effects / Q000379:methods; D017778:Vaccines, Combined / Q000008:administration & dosage / Q000009:adverse effects / Q000276:immunology
chemical_list: D000914:Antibodies, Viral; D019433:Chickenpox Vaccine; D022542:Measles-Mumps-Rubella Vaccine; D017778:Vaccines, Combined; C050102:measles, mumps, rubella, varicella vaccine
keywords: MMRV vaccine; Singapore; Taiwan; immunogenicity; newly established working seed virus stock; safety