Clinical Trial Info

Consistency Study of GlaxoSmithKline (GSK) Biologicals' MMR Vaccine (209762) (Priorix) Comparing Immunogenicity and Safety to Merck & Co., Inc.'s MMR Vaccine (M-M-R II), in Children 12 to 15 Months of Age

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This Phase 3 study will evaluate the consistency of the immune response to three different lots of GSK Biologicals' trivalent investigational MMR vaccine (referred to as INV_MMR vaccine, throughout this document) and compare its immunogenicity to the US standard of care comparator vaccine (M-M-R II, Merck and Co., Inc., referred to as COM_MMR throughout this document) in children during their second year of life.

The INV_MMR vaccine will be given as one of three consistency lots manufactured to target potencies designated as INV_MMR_L1, INV_MMR_L2 and INV_MMR_L3. The COM_MMR vaccine will be given as one of two lots designated COM_MMR_L1 and COM_MMR_L2 and will be analysed as pooled lots within the study. The MMR vaccine will be co-administered with Varivax (VV), Havrix (HAV) and (in the US sub-cohort only) Prevnar 13 (PCV-13) which are routinely administered to children of this age in the US.


Journal of the Pediatric Infectious Diseases Society published the results of this trial on April 30, 2020.

Results: Immunoresponses after vaccination with MMR-RIT were robust and non-inferior to those after vaccination with the MMR II. Immunogenicity of the 3 production lots of MMR-RIT was consistent; more than 97% of the children had a seroresponse to MMR components. The coadministered vaccines elicited similar immune responses in the MMR-RIT and MMR II groups. Both MMR vaccines resulted in comparable reactogenicity profiles, and no safety concerns were detected.

Conclusions: If licensed, the MMR-RIT could provide a valid option for the prevention of measles, mumps, and rubella in children in the United States and would reduce potential risks of a vaccine shortage.