On Dec. 7, 2022, Novavax announced that Health Canada had approved a supplement to a New Drug Submission (sNDS) for Nuvaxovid (COVID-19 Vaccine (Recombinant protein, Adjuvanted)) (NVX-CoV2373) for active immunization to prevent coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) as a primary series of two doses in adolescents aged 12 through 17.

The approval of the sNDS was based on data from the ongoing pediatric expansion of the Phase 3 PREVENT-19 trial of 2,247 adolescents aged 12 through 17 years across 75 sites in the U.S., to evaluate the safety and effectiveness of Nuvaxovid. In the pediatric expansion, the effectiveness analysis was based on antibody titers that were shown to be higher in adolescents than in young adults. Effectiveness was supported by clinical efficacy showing that Nuvaxovid provided clinical protective efficacy of 79.5% (95% CI: 46.8%, 92.1%) overall at a time when the Delta variant was the predominant circulating SARS-CoV-2 strain.