Rubella, live attenuated

Efficacy

Formal studies to evaluate the efficacy of rubella vaccine have not been performed. However, the efficacy of rubella vaccine has been demonstrated in numerous studies.

Efficacy of the rubella components of rubella vaccine was previously established in a series of double-blind controlled field trials with the monovalent vaccines which demonstrated a high degree of protective efficacy. In these studies seroconversion in response to vaccination against rubella paralleled protection from this disease.

More than 518 million doses of the rubella vaccine have been distributed worldwide (1978 to 2007). Widespread use of a 2-dose vaccination schedule in the United States and countries such as Finland and Sweden has led to a >99% reduction in the incidence of the targeted disease.

Immunogenicity

Immunogenicity was studied in children 12 through 23 months of age with a negative clinical history of rubella who participated in 5 randomized clinical trials. The immunogenicity of the current refrigerator-stable formulation was shown to be similar to the immunogenicity of the earlier formulation of the rubella vaccine six weeks after a single dose of the vaccine. The immunogenicity of a single dose of an earlier formulation of the rubella vaccine was comparable to the immunogenicity of a single dose of its individual component rubella vaccine, currently used in routine vaccination in some countries.

Clinical trials involving 6987 subjects who received rubella vaccine demonstrated detectable immune responses to rubella in a high proportion of individuals. The presence of detectable antibody was assessed by an appropriately sensitive enzyme-linked immunosorbent assay (ELISA) for rubella. Following a single dose of rubella vaccine, the vaccine response rates were 98.8% for rubella.

Not applicable.

Traditional non-clinical studies were not performed, but there are no non-clinical concerns considered relevant to clinical safety.