For more than 40 years, only a single measles, mumps and rubella (MMR) vaccine formulation (M-M-R-II from Merck) has been available in the United States. In June 2022, a second MMR vaccine (Priorix from GlaxoSmithKline) was approved by the Food and Drug Administration and unanimously recommended by the Advisory Committee on Immunization Practices (ACIP) of the Centers for Disease Control and Prevention.
No change to AAP policy was required based on ACIP’s recommendation because specific MMR formulations are not mentioned in relevant Red Book chapters (see resources). Existing AAP recommendations apply to both available MMR vaccines.
ACIP concluded that Priorix is safe, immunogenic and noninferior to M-M-R-II based on data from four randomized trials and several observational studies. It recommended that Priorix and M-M-R-II should be considered fully interchangeable for all indications for which MMR is recommended. These indications include those listed on the vaccine package inserts and specific off-label recommended uses, including vaccination of children ages 6-11 months prior to international travel or during a measles outbreak; as a third dose for at-risk children during a mumps outbreak; or as measles postexposure prophylaxis.
Dr. Ratner is a member of the AAP Committee on Infectious Diseases.