Novavax Expands Phase III COVID-19 Vaccine Trial to Include Adolescents

Novavax said Monday that it has initiated a pediatric expansion of the Phase III PREVENT-19 trial to test its experimental coronavirus vaccine NVX-CoV2373 in children ages 12 to 17 years old.

“Through the expansion…we hope to build upon the encouraging safety and efficacy data generated to-date in adults for our vaccine candidate and to play a significant global role in offering vaccination to as many people as possible across age groups,” remarked R&D head Gregory Glenn.

Earlier this year, Novavax said it had completed enrollment of 30,000 adult volunteers in PREVENT-19, which began in December and is being run in the US and Mexico. The trial is evaluating two intramuscular injections of NVX-CoV2373 or placebo, administered 21 days apart. The additional arm of the trial will evaluate the efficacy, safety and immunogenicity of NVX-CoV2373 in up to 3000 adolescents aged 12 to 17 across up to 75 sites in the US.

Novavax noted that a blinded crossover is planned at six months after the initial set of vaccinations to ensure all trial participants receive active vaccine. Study volunteers will be monitored for safety for up to two years following the final dose. The company said it will share an update regarding the pediatric arm of PREVENT-19 during the World Vaccine Congress taking place later this week.

Novavax recently reported that NVX–CoV2373 had overall efficacy of 89.7% at the final analysis of a late-stage UK trial involving more than 15,000 participants, including efficacy rates of 96.4% and 86.3%, respectively, against the original strain of SARS-CoV-2 and the B.1.1.7 variant. It was also found to provide 100% protection against severe disease. Meanwhile, GlaxoSmithKline has agreed to help produce up to 60 million doses of NVX-CoV2373 for use in the UK. The vaccine is not yet authorized anywhere in the world, but is expected to be submitted for review in the UK during the second quarter.

Pfizer and its partner BioNTech have recently filed with US and EU regulators to have their COVID-19 vaccine authorized for use in adolescents as young as 12 years old. Johnson & Johnson and Moderna are also running trials evaluating their respective COVID-19 vaccines in pediatric populations, while a UK study testing AstraZeneca’s Vaxzevria in children was paused recently amid concerns that it may be linked to rare cases of blood clots seen in adult recipients.