Moderna announces TeenCOVE study of its COVID-19 vaccine (mRNA-1273) in adolescents meets primary endpoint
In the study, no cases of COVID-19 were observed in participants who had received two doses of the Moderna COVID-19 vaccine using the primary definition. In addition, a vaccine efficacy of 93% in seronegative participants was observed starting 14 days after the first dose using the secondary CDC case definition of COVID-19, which tested for milder disease. This study, known as the TeenCOVE study, enrolled more than 3,700 participants ages 12 to less than 18 years in the U.S. The Company plans to submit these data to regulators globally in early June. In this Phase II/III study, 3,732 adolescent participants ages 12 to less than 18 years were enrolled and randomized 2:1 to two 100 µg doses of mRNA-1273 or placebo. The primary endpoint of non-inferior immunogenicity versus the Phase III adult study comparator group was met. After two doses, no cases of COVID-19 were observed in the vaccine group using the case definition from the adult Phase III COVE study, compared to 4 cases in the placebo group, resulting in a vaccine efficacy of 100% starting 14 days after the second dose. Because the incidence rate of COVID-19 is lower in adolescents, a secondary case definition based on the CDC definition of COVID-19 was also evaluated to include cases presenting with milder symptoms. Using the CDC definition, which requires only one COVID-19 symptom and a nasopharyngeal (NP) swab or saliva sample positive for SARS-CoV-2 by RT-PCR, a vaccine efficacy of 93% after the first dose was observed.