General Information

Priorix is a vaccine for Measles, Mumps and Rubella

Priorix is specifically indicated for active immunization for the prevention of measles, mumps and rubella (MMR) in individuals 12 months of age and older.

Priorix is supplied as a suspension for subcutaneous injection.  Each dose is approximately 0.5 mL. The first dose is administered at 12 through 15 months of age. The second dose is administered at 4 through 6 years of age.

Mechanism of Action

Humoral immune responses against measles, mumps, and rubella viruses induced by Priorix were measured by enzyme-linked immunosorbent assays (ELISAs). IgG antibodies measured by the ELISAs used in clinical studies of Priorix have been shown to correlate with the presence of neutralizing antibodies that have been associated with protection.

Side Effects

Adverse effects associated with Priorix may include, but are not limited to, the following:

12 through 15 months of age:

• local reactions were pain and redness
• systemic reactions were irritability, loss of appetite, drowsiness and fever

4 through 6 years of age:

• local reactions were pain, redness and swelling
• systemic reactions were loss of appetite drowsiness and fever

7 years of age and older:

• local reactions were pain and redness

Clinical Trial Results

The FDA approval of Priorix was based on 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. Clinical trials evaluated the safety and efficacy while mirroring the ages of recommended inoculation. Additionally, the studies were designed to compare efficacy against already approved competition. Priorix demonstrated non-inferiority against the competitor in these trials.