title: Analysis of safety data in children after receiving two doses of ProQuad® (MMRV).
abstract: BACKGROUND
  In randomized clinical studies, over 11,800 children, 12 months to 6 years of age, were administered ProQuad(®), a combination measles, mumps, rubella, and varicella vaccine (MMRV). This paper describes the safety following a 2-dose regimen of MMRV administered to children in the second year of life.
  
  
  METHODS
  Safety data from five clinical studies were combined for all children who were scheduled to receive two doses of MMRV ∼3-6 months apart. All vaccinated children were followed for safety following each dose of MMRV.
  
  
  RESULTS
  Of 3112 children who received a first dose of MMRV, 2780 (89.3%) received a second dose of MMRV. Overall, 70.5% and 57.7% of children reported ≥1 adverse experiences following first and second doses of MMRV, respectively. Injection-site redness was statistically significantly higher postdose 2 than postdose 1, while injection-site pain/tenderness was statistically significantly higher postdose 1 compared to postdose 2. Rashes were statistically significantly lower postdose 2 compared to postdose 1. Ten febrile seizures (8 postdose 1, 2 postdose 2) were reported following MMRV vaccination. The incidence of febrile seizures postdose 1 of MMRV was 0.26% (8/3019) compared to 0.07% (2/2695) postdose 2 of MMRV.
  
  
  CONCLUSIONS
  Administration of two doses of MMRV has an acceptable safety profile in children 12 to 23 months of age. There is a small increase in the risk of febrile seizures following the first dose of MMRV as compared to the component vaccines, but the risk for any individual child is relatively low.
authors.affiliation: Merck & Co., Inc, Whitehouse Station, NJ, United States. Electronic address: stephanie_klopfer@merck.com.
authors.forename: Stephanie O
authors.initials: SO
authors.lastname: Klopfer
authors.affiliation: Merck & Co., Inc, Whitehouse Station, NJ, United States.
authors.forename: Jon E
authors.initials: JE
authors.lastname: Stek
authors.affiliation: Merck & Co., Inc, Whitehouse Station, NJ, United States.
authors.forename: Maria
authors.initials: M
authors.lastname: Petrecz
authors.affiliation: Primary Physicians Research, Pittsburgh, PA, United States.
authors.forename: Keith S
authors.initials: KS
authors.lastname: Reisinger
authors.affiliation: Cincinnati Children's Hospital, Cincinnati, OH, United States.
authors.forename: Steven B
authors.initials: SB
authors.lastname: Black
authors.affiliation: Merck & Co., Inc, Whitehouse Station, NJ, United States.
authors.forename: Michelle G
authors.initials: MG
authors.lastname: Goveia
authors.affiliation: Merck & Co., Inc, Whitehouse Station, NJ, United States.
authors.forename: Ouzama
authors.initials: O
authors.lastname: Nicholson
authors.affiliation: Merck & Co., Inc, Whitehouse Station, NJ, United States.
authors.forename: Julie L
authors.initials: JL
authors.lastname: Gardner
authors.affiliation: Merck & Co., Inc, Whitehouse Station, NJ, United States.
authors.forename: Anthony D
authors.initials: AD
authors.lastname: Grosso
authors.affiliation: Merck & Co., Inc, Whitehouse Station, NJ, United States.
authors.forename: Michelle L
authors.initials: ML
authors.lastname: Brown
authors.affiliation: Merck & Co., Inc, Whitehouse Station, NJ, United States.
authors.forename: Barbara J
authors.initials: BJ
authors.lastname: Kuter
authors.affiliation: Merck & Co., Inc, Whitehouse Station, NJ, United States.
authors.forename: Florian P
authors.initials: FP
authors.lastname: Schödel
mesh_terms: D019433:Chickenpox Vaccine / Q000008:administration & dosage* / Q000009:adverse effects*; D064420:Drug-Related Side Effects and Adverse Reactions / Q000453:epidemiology* / Q000473:pathology*; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D022542:Measles-Mumps-Rubella Vaccine / Q000008:administration & dosage* / Q000009:adverse effects*; D016032:Randomized Controlled Trials as Topic; D003294:Seizures, Febrile / Q000453:epidemiology / Q000473:pathology; D017778:Vaccines, Combined / Q000008:administration & dosage / Q000009:adverse effects
chemical_list: D019433:Chickenpox Vaccine; D022542:Measles-Mumps-Rubella Vaccine; D017778:Vaccines, Combined; C050102:measles, mumps, rubella, varicella vaccine
keywords: Integrated analyses; MMRV; NCT00109343; NCT00312858; NCT00326183; NCT00975507; NCT00986232; ProQuad(®); Safety; Tolerability