Measles, mumps, rubella vaccine (Priorix; GSK-MMR): a review of its use in the prevention of measles, mumps and rubella.

GSK-MMR (Priorix) is a trivalent live attenuated measles, mumps and rubella (MMR) vaccine which contains the Schwarz measles, the RIT 4385 mumps (derived from the Jeryl Lynn mumps strain) and the Wistar RA 27/3 rubella strains. GSK-MMR as a primary vaccination demonstrated high immunogenicity in clinical trials in >7500 infants aged 9-27 months, and was as immunogenic as Merck-MMR (MMR II). However, antimumps seroconversion rates and geometric mean titres (GMTs) were significantly higher in infants receiving GSK-MMR compared with Berna-MMR (Triviraten trade mark ) recipients. Coadministration of GSK-MMR with a varicella vaccine (Varilrix; GSK-MMR/V) did not significantly affect the immunogenicity of GSK-MMR. A persistent immune response to GSK-MMR has been demonstrated in follow-up data from several randomised trials. GMTs for measles, mumps and rubella antibodies remained high in GSK-MMR recipients 1-2 years post-vaccination and were similar to those in Merck-MMR recipients. The immunogenicity of GSK-MMR was high, and similar to that of Merck-MMR, when used as a second dose in children aged 4-6 or 11-12 years who had received a primary vaccination with Merck-MMR in their second year of life. Although there are no protective efficacy data concerning the GSK-MMR vaccine to date, the rubella Wistar RA 27/3 rubella and Schwarz measles strains have well established protective efficacy; the new RIT 4385 mumps strain is expected to afford similar protection from mumps to that achieved with mumps vaccines that contain the Jeryl Lynn mumps strain (e.g. Merck-MMR). GSK-MMR was well tolerated as a primary or secondary vaccination, and in most clinical studies comparing GSK-MMR with Merck-MMR as a primary vaccination in infants, GSK-MMR was associated with significantly fewer local adverse events (e.g. pain, swelling and redness). The incidence of local adverse events with GSK-MMR, GSK-MMR/V or Berna-MMR was similar. GSK-MMR and Merck-MMR were associated with similar rates of fever, rash and parotid gland swelling, but Berna-MMR was associated with a lower incidence of fever. In conclusion, GSK-MMR is a highly immunogenic MMR vaccine with good tolerability. In clinical trials, the immunogenicity of GSK-MMR was similar to that of Merck-MMR, and the mumps component was more effective at eliciting seroprotection than that of Berna-MMR. Furthermore, GSK-MMR causes fewer injection-site adverse events than Merck-MMR. As such, GSK-MMR is an attractive alternative for immunisation against measles, mumps and rubella.