Gregory A.Anitta A.Andrea B.Archana C.Nan-Chang C.Clemente D.P.Byron H.LI-MIN HUANGRobert J.Nicola K.Michael L.Ming-Chih L.Marita P.Kwabena S.Peter S.Jerry T.Timo V.Leonard W.Tsung Zu W.Stephane C.Christophe D.Michael P.Remon A.-E.Ouzama H.Carmen B.2021-06-242021-06-2420182164-5515https://www.scopus.com/inward/record.uri?eid=2-s2.0-85053028105&doi=10.1080%2f21645515.2018.1502527&partnerID=40&md5=9c3e494c1fa6871f00b0f4787407df40https://scholars.lib.ntu.edu.tw/handle/123456789/566380The titer of live attenuated viral vaccines, such as MMR vaccines, varies between batches and over the shelf-life of a batch, with the highest titer expected at batch release. As higher titers may theoretically lead to increased reactogenicity, we compared the safety profile of an upper-range release titer MMR-RIT lot with commercial MMR II lots in a phase III, randomized, controlled study (NCT02184572). We vaccinated 1736 children with MMR-RIT (N?=?1164) or MMR II (N?=?572), both administered as first doses with varicella, hepatitis A, and pneumococcal conjugate vaccines at 12–15?months of age. The incidence of fever 5–12?days post-vaccination was comparable following MMR-RIT and MMR II vaccination: 4.2% vs 3.1% (difference: 1.1%) for fever >?39.0°C and 18.2% vs 17.1% (difference: 1.1%) for fever ??38.0°C, which met the primary objective. Two cases of febrile convulsions (one considered vaccination-related) were reported within 43?days post-MMR-RIT. During Days 0–42, rashes were reported for 24.4% (MMR-RIT) and 27.4% (MMR II) of children; measles/rubella-like rashes for 5.8% and 4.7%, respectively. Measles-like illnesses were reported for 1.5% (MMR-RIT) and 0.9% (MMR II) of children 5–12?days post-vaccination. One serious adverse event, immune thrombocytopenic purpura following MMR II vaccination, was considered vaccination-related. Immune responses were similar in both groups. In summary, the safety profile of an upper-range release titer MMR-RIT lot was in line with that of commercial MMR II lots, with similar rates of fever and other MMR-specific symptoms and low rates of measles-like illnesses reported with both vaccines. ? 2018, ? 2018 GlaxoSmithKline Biologicals SA. Published with license by Taylor & Francis Group, LLC.measles; MMR vaccine; mumps; release titer; rubella; safety[SDGs]SDG3chickenpox vaccine; hepatitis A vaccine; immunoglobulin G; m m r ii; measles mumps rubella vaccine; Pneumococcus vaccine; rubella antibody; antibody response; antibody titer; Article; child; cohort analysis; controlled study; drug safety; drug tolerability; enzyme linked immunosorbent assay; febrile convulsion; female; human; idiopathic thrombocytopenic purpura; immune response; immunization; immunogenicity; male; measles; multicenter study; mumps; phase 3 clinical trial; preschool child; randomized controlled trial; rash; rubella; single blind procedure; single drug dose; temperature; vaccinationjournal article10.1080/21645515.2018.1502527301183862-s2.0-85053028105