On Dec. 10, 2020, Moderna announced that the first adolescent participants had been dosed in the Phase 2/3 study of mRNA-1273, the Company’s vaccine candidate against COVID-19, in adolescents ages 12 to less than 18. The study was conducted in collaboration with the Biomedical Advanced Research and Development Authority.

This randomized, controlled Phase 2/3 study will evaluate the safety, reactogenicity and immunogenicity of two vaccinations of mRNA-1273 given 28 days apart. The Company intends to enroll 3,000 adolescent participants in the U.S. ages 12 to less than 18 years. Each participant was assigned to receive a placebo or a 100 μg dose at both vaccinations. Participants will be followed through 12 months after the second vaccination. Vaccine effectiveness was either inferred through achieving a correlate of protection (if established) or through immunobridging to the adult population. Evaluation of vaccine safety and reactogenicity was also a primary endpoint of the study.