Priorix MMR Vaccine Clinical Trials, Dosage, Efficacy, Side Effects, Usage
GlaxoSmithKline (GSK) Priorix is a trivalent measles, mumps, and rubella (MMR) vaccine, a lyophilized mixed preparation of the attenuated Schwarz measles virus, the mumps virus derived from the Jeryl-Lynn strain, and the rubella virus Wistar RA 27/3. The measles and mumps components of the vaccine are produced in chick embryo cell culture and may contain traces of egg protein. Priorix has demonstrated noninferiority of the immune response compared to the M-M-R II® vaccine. Immune response to any antigens in Priorix or the coadministered vaccines was similar to the immune responses obtained when M-M-R II was coadministered with the same routine U.S. pediatric vaccines.
On June 23, 2022, Elisabeth Krow-Lucal, Ph.D. MPH Measles, Mumps, Rubella Vaccines Work Group, U.S. Centers for Disease Control and Prevention (CDC) Advisory Committee on Immunization Practices (ACIP), presented: Priorix for Prevention of MMR. Then, on November 18, 2022, the CDC's MMWR: Priorix Recommendations of the ACIP - United States, 2022, confirmed that Priorix and the M-M-R II vaccine are considered fully interchangeable, including for all off-label recommended uses—the ACIP Evidence to Recommendations Framework for the Use of Priorix to Prevent MMR in October 2022. The CDC says Priorix may be used in accordance with the existing MMR recommendations, both on- and off-label. On February 9, 2023, the American Academy of Pediatrics supported the CDC's recommendation on offering Priorix in the U.S.
The U.S. FDA approved (STN:125748) Priorix, which became available in the U.S. in 2022. Priorix contains 9 mg of sorbitol, 6.5 nanograms of para-aminobenzoic acid per dose, and 334 micrograms of phenylalanine per dose. In addition, this vaccine has a trace amount of neomycin. Codes: CVX Code: 03, MVX Code: SKB, CPT Code: 90707, ICD-10-CM Code: Z23.
As of 2025, more than 800 million Priorix doses have been distributed. It is currently licensed in over 100 countries, including Canada, England, Europe, Ireland, Switzerland, New Zealand, and the United States.
London-based GlaxoSmithKline plc (GSK) is a global healthcare company with a special purpose: to help people do more, feel better, and live longer. For further information, please get in touch with GSK.
Priorix Vaccine Availability 2025
Priorix was first registered in Germany in 1997. In March 2012, the European Medicines Agency (EMA) completed a review of Priorix. In June 2022, the U.S. Food and Drug Administration (FDA) approved Priorix (STN:125748) to prevent MMR in individuals 12 months of age and older. Priorix TETRA has been approved in Canada. In the U.S., PRIORIX was added to the CDC Vaccines for Children program.
Priorix Vaccine Indication
Priorix is indicated to protect against MMR. It works by helping the body make antibodies that protect your child against these diseases.
Priorix Vaccine Dosage
Globally, Priorix is recommended for use in individuals aged ≥9 months, according to a 1- or 2-dose schedule, depending on the country. Priorix is administered as a subcutaneous or Intramuscular injection in the deltoid region or the anterolateral area of the thigh. A single 0.5 mL dose of the reconstituted vaccine is recommended. A second dose of MMR is recommended at least one month after the first dose for better measles protection. There is no difference between the first and second vaccine doses concerning the frequency category for the adverse reactions, except for pain at the injection site, which was "Common" after the first and "Very common" after the second vaccine dose.
Priorix-TETRA MMRV Vaccine
PRIORIX-TETRA is a sterile lyophilized mixed preparation containing the attenuated Schwarz measles virus strain, the RIT 4385 strain of mumps virus, the Wistar RA 27/3 rubella virus strain, and the OKA strain of the varicella-zoster virus. Each virus strain is produced separately in either chick embryo cells (mumps and measles) or MRC-5 human diploid cells (rubella and varicella).
Priorix Immunocompromised
There is limited data on using Prioeix in immunocompromised subjects; therefore, vaccination should be considered cautiously, and only when, in the physician's opinion, the benefits outweigh the risks (e.g., asymptomatic HIV subjects).
Priorix Contraindications
Contraindications for Priorix are severe allergic reaction (e.g., anaphylaxis) to any component of Priorix or after a previous dose of any measles, mumps, and rubella-containing vaccine; severe immunodeficiency; and pregnancy or planning to become pregnant within the next month.
Priorix Women
Pregnant women must not be vaccinated with Priorix, says GSK. However, fetal damage has not been documented when MMR vaccines have been given to pregnant women. Therefore, inadvertent vaccination of unknowingly pregnant women with MMR-containing vaccines should not be a reason for the termination of pregnancy. Nevertheless, women of childbearing potential should be advised to avoid pregnancy for one month following vaccination. Furthermore, there is no human data regarding use in breastfeeding women. Nursing mothers may be vaccinated where the benefit outweighs the risk in the health professional's judgment.
Priorix Administration
Reconstitute the Lyophilized Antigen Component, Live only with the accompanying Sterile Water Diluent Component to form PRIORIX. The reconstituted vaccine should be a clear peach-to-fuchsia-pink suspension. Parenteral drug products should be visually inspected for particulate matter and discoloration before administration, whenever the solution and container permit. If either of these conditions exists, do not administer the vaccine. Instead, administer PRIORIX immediately after reconstitution. If not used immediately, store refrigerated at 36° to 46° F (2° to 8°C) and administer within 8 hours. Discard the reconstituted vaccine if it is not used within 8 hours.
Priorix Side Effects
Side effect information is available in the public domain via the Oxford Vaccine Knowledge Project. There is a risk of febrile seizures following immunization with Priorix, and thrombocytopenia and thrombocytopenic purpura have been reported following Priorix vaccination. A summary of studies involving MMR studies can be found on their website: https://vk.ovg.ox.ac.uk/vk/mmr-vaccine.
Priorix-TETRA Vaccine
PRIORIX-TETRA is a sterile lyophilized mixed preparation containing the attenuated Schwarz measles virus strain, the RIT 4385 strain of mumps virus (derived from the Jeryl Lynn strain), the Wistar RA 27/3 rubella virus strain, and the OKA strain of the varicella-zoster virus. Each virus strain is produced separately in either chick embryo cells (mumps and measles) or MRC-5 human diploid cells (rubella and varicella). Although PRIORIX-TETRA contains live viruses, they are too weak to cause severe disease in healthy people. However, some spots, blisters, and fever may occasionally appear in the first two weeks after vaccination.
Priorix Vaccine News
November 23, 2023 - Switzerland's Federal Office for National Economic Supply confirmed a shortage of Priorix vaccines.
February 10, 2023 - The AAFP and several other organizations co-released the 2023 adult and childhood/adolescent immunization schedules.
November 23, 2022 - The U.S. CDC and the WHO announced nearly 40 million children are susceptible to the growing measles threat.
November 18, 2022 - U.S. CDC ACIP Recommendation: Priorix is recommended according to the existing MMR vaccination schedules and is an off-label option for preventing measles, mumps, and rubella.
June 6, 2022 - GSK announced the U.S. FDA approved the Priorix vaccine for most people over the age of one year.
February 23, 2022 - Remon Abu-Elyazeed, MD, Ph.D., presented 'Overview of GSK's MMR Vaccine' during the CDC's ACIP vaccine committee meeting.
August 2, 2021 - GSK submitted a Biologics License Application to the U.S. FDA for PRIORIX and is seeking approval for active immunization against MMR infection.
March 24, 2021 - Vaccine manufacturers across the globe have been partnering with organizations such as the WHO, UNICEF, and GAVI Alliance to improve their vaccination programs and reach the maximum number of people to offer vaccines. Despite several governmental initiatives, measles is a leading cause of death among young children.
April 30, 2020 - Study: Immunogenicity and Safety of an MMR Vaccine Administered as the First Dose to Children Aged 12 to 15 Months: A Phase III, Randomized, Noninferiority, Lot-to-Lot Consistency Study. Conclusions: If licensed, the MMR-RIT could provide a valid option for preventing measles, mumps, and rubella in children in the United States and help reduce the risk of a vaccine shortage.
January 12, 2020 - A study published in the Pediatric Infectious Disease Society concluded that, if licensed, the Priorix / MMR-RIT vaccine could provide a valid option for preventing MMR in children 12 to 15 months old in the U.S.
March 22, 2019 - A phase 3 study published in the Pediatric Infectious Diseases Society Journal found that GlaxoSmithKline's MMR vaccine was safe and effective in healthy children.
Priorix Vaccine Clinical Trials
GSK continues to test the safety and efficacy of Priorix in clinical trials.
