The vaccine efficacy of the Novavax’s NVX-CoV2373 was 79.5% in adolescents.
Teenager wearing face mask covering | Image Credit: © Seventyfour - © Seventyfour - stock.adobe.com.
More than 20% of COVID-19 infections and 0.4% of related fatalities occur in children. As COVID-19 gradually becomes endemic, it’s more important than ever to ensure all eligible persons are vaccinated to protect themselves and others.
NVX-CoV2373, the recombinant spike (S) protein-based COVID-19 vaccine from Novavax, was recently approved under emergency use authorization for adolescents 12-17 years of age. Previously available only to adults 18 years and older, NVX-CoV2373 offers an alternative to the authorized messenger RNA (mRNA) COVID-19 vaccines.
The results of a randomized clinical trial of NVX-CoV2373 were recently published in JAMA Network Open. The phase 3 trial sought to determine whether NVX-CoV2373 was safe, immunogenic, and efficacious in preventing COVID-19 in adolescents aged 12-17 years.
The study population included adolescents 12-17 years of age, who were either healthy or with stable chronic medical conditions. A total of 2232 participants were included and randomized 2:1 to receive injections of either NVX-CoV2373 or placebo, administered 21 days apart. Exclusion criteria included a prior laboratory-confirmed COVID-19 infection or known immunosuppression.
The 1487 NVX-CoV2373 recipients and 745 placebo recipients averaged 52.5% male, 74.4% White, and 13.8 years of age. A total of 20 mild COVID-19 cases occurred an average of 64 days after intervention, 14 in placebo recipients and 4 in NVX-CoV2373 vaccine recipients, for a vaccine efficacy of 79.5%.
Notably, vaccine efficacy against the Delta variant, the only COVID-19 strain recognized by genomic sequencing, was 82.0%. Vaccine reactogenicity was mild-to-moderate and brief; reactogenicity occurred with greater frequency after the second dose of NVX-CoV2373. Serious adverse events were determined to be rare, and evenly dispersed between the NVX-CoV2373 and placebo recipients.
The investigators determined that the NVX-CoV2373 COVID-19 vaccine was safe, immunogenic, and efficacious against COVID-19 infection in adolescents 12-17 years of age. These findings are significant, as more than 22% of adolescents have yet to receive an mRNA COVID-19 vaccine.
“A favorable safety profile, convenient storage and transportation requirements, and induction of broad, cross-reactive immune responses with the potential to provide protection against new variants suggest that NVX-CoV2373 offers an important choice for vaccination of younger individuals in the fight against the current COVID-19 pandemic worldwide,” the study authors concluded.
This article was initially published by our sister publication, Contagion Live.
Infant RSV hospitalization rates 28%, 43% lower this season vs pre-COVID seasons
May 9th 2025"These findings support Advisory Committee on Immunization Practices’ recommendations for maternal vaccination or nirsevimab to protect against severe RSV disease in infants," wrote the MMWR study investigators.