Novavax has expanded the ongoing Phase III PREVENT-19 clinical trial of its recombinant protein Covid-19 vaccine candidate, NVX-CoV2373, to include a paediatric arm.
NVX-CoV2373 is made from the genetic sequence of the first SARS-CoV-2 strain. It is adjuvanted with the company’s saponin-based Matrix-M to boost immune response and neutralising antibodies.
The newly added trial arm will assess the efficacy, safety and immunogenicity of the vaccine candidate in up to 3,000 adolescents aged 12 to 17 years at up to 75 sites in the US.
Subjects will receive two doses of either the vaccine candidate or placebo, given 21 days apart. Two-thirds of participants will be given intramuscular doses of NVX-CoV2373, while one-third will be given a placebo.
Novavax intends to carry out a blinded crossover six months after administering the initial set of vaccines to make sure that all subjects receive active vaccine. A follow-up for safety will be conducted for two years after the final dose.
Novavax Research and Development president Gregory Glenn said: “Through the expansion of our PREVENT-19 clinical trial, 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 to end the suffering caused by the pandemic.”
The vaccine candidate is currently being analysed in a Phase III trial in the UK, which showed full protection against severe disease.
Trial data also showed that the vaccine had an overall efficacy of 89.7%, with a 96.4% and 86.3% efficacy against the original virus strain and the B.1.1.7/501Y.V1 variant, respectively.
NVX-CoV2373 is also being evaluated in a Phase IIb trial in South Africa and a Phase I/II continuation in the US and Australia.
The vaccine candidate had demonstrated ability to stimulate antibodies that hinder the binding of spike protein to cellular receptors and offered protection from infection and disease in preclinical studies.