New Japanese rubella vaccine: comparative trials

Area of Science:

• Virology
• Immunology
• Vaccinology

Background:

• Rubella virus infections pose a significant public health concern, particularly for pregnant women due to the risk of congenital rubella syndrome.
• Development of safe and effective rubella vaccines is crucial for global rubella eradication efforts.

Purpose of the Study:

• To evaluate the immunogenicity and reactogenicity of a new Japanese rubella vaccine (To-336) in comparison to established vaccines.
• To assess the incidence of joint symptoms following vaccination and explore potential contributing factors.

Main Methods:

• A comparative study involving 142 seronegative volunteers vaccinated with Cendehill, HPV77.DE-5, RA27/3, or To-336 rubella vaccines.
• Geometric Mean Antibody Titre (G.M.T.) was measured to assess immunogenicity.
• Incidence of adverse reactions, specifically joint symptoms, was recorded and analyzed.

Main Results:

• The To-336 vaccine elicited a slightly higher G.M.T. (65.7) compared to HPV77.DE-5 (63.1) and RA27/3 (61.9), while Cendehill showed a lower G.M.T. (39.3).
• The To-336 vaccine was associated with the lowest incidence of joint symptoms.
• Joint symptoms were observed in 81% of cases within seven days of menstruation, independent of oral contraceptive use.

Conclusions:

• The To-336 rubella vaccine demonstrates favorable immunogenicity and a reduced risk of joint-related adverse events.
• While Japanese rubella virus strains show potential for being non-teratogenic, further epidemiological data on congenital rubella infection incidence in Japan is required for confirmation.