Priorix goes up against Merck’s M-M-R II vaccine in the US. “We’re proud to make Priorix available in the US for the first time, adding a choice for providers to help protect patients against these highly-contagious diseases and to further strengthen offerings in our pediatric vaccine portfolio,” said Judy Stewart, Senior Vice President and Head of US Vaccines, GSK.
Priorix was first registered in Germany in 1997 and is now licenced in more than 100 countries worldwide, including across Europe, Canada, Australia and New Zealand. More than 800 million doses have been distributed to date.
MMR vaccination rates
Measles, mumps and rubella are acute and highly-contagious viral diseases. In recent years, measles outbreaks have occurred in the US and globally, with more than 400,000 cases confirmed in 2019 (reversing decades of progress toward measles elimination in many countries).
CDC recommends children get two doses of an MMR vaccine, starting with the first dose at 12 through 15 months of age, and the second dose at 4 through 6 years of age. Teens and adults should also be up to date on their MMR vaccination.
But according to a recent US Centers for Disease Control and Prevention (CDC) report, vaccines ordered through the federal CDC Vaccines For Children program dropped more than 10% (around half of children in the US are vaccinated through this program). The report also noted 400,000 fewer children entered kindergarten in the 2020-2021 school year than expected nationally, meaning those children may not be up to date on childhood immunizations like their MMR vaccination.
GSK states that the safety of Priorix for US approval was evaluated in six clinical studies, in which a total of 12,151 participants (6,391 in the US) received at least one dose of Priorix: 8,780 children (4,148 in the US) 12 through 15 months of age; 2,917 children (1,950 in the US) 4 through 6 years of age; and 454 adults and children (293 in the US) 7 years of age and older.
The most commonly reported adverse reactions were pain, redness, swelling, loss of appetite, irritability, drowsiness and fever.
The efficacy of Priorix was demonstrated based on immunogenicity data versus M-M-R-II.
The FDA approval states Priorix may be administered as a two-dose vaccine regimen or administered as a second dose after a different MMR vaccine.
Priorix is scheduled to be on the agenda for the June CDC Advisory Committee on Immunization Practices (ACIP) meeting for consideration of formal inclusion into the vaccine schedule and recommendations.
GSK’s vaccine portfolio in the US includes Boostrix, Cervarix, Fluarix, Menveo, Rotarix and Shingrix.