US-based biotechnology firm Novavax has started the first Phase III clinical trial of its potential Covid-19 vaccine, NVX-CoV2373, in the UK.
Performed in collaboration with the UK Government’s Vaccines Taskforce, the trial will investigate the safety, efficacy and immunogenicity of NVX-CoV2373.
The study is designed to recruit up to 10,000 participants aged 18 to 84 years, with and without relevant comorbidities, over the coming four to six weeks.
It is intended to involve at least 25% of subjects aged above 65 years, and also prioritise groups most impacted by Covid-19, including racial and ethnic minorities.
During the randomised, placebo-controlled, observer-blinded trial, 50% of volunteers will be given two intramuscular injections of the vaccine candidate, 21 days apart, while the remaining will receive placebo.
The vaccine dose will consist of 5µg of protein antigen and 50µg Matrix‑M adjuvant.
Novavax added that under a co-administration sub-study, up to 400 participants will also be administered with a licensed seasonal influenza vaccine.
The first primary endpoint of the Phase III trial is first occurrence of PCR-confirmed symptomatic Covid-19 with onset at least seven days following the second vaccination in subjects with no prior SARS-CoV-2 infection.
Also, the trial will assess second primary endpoint as first occurrence of PCR-confirmed symptomatic moderate or severe Covid-19 with onset at least seven days after the second vaccination in those who had no previous infection from the virus.
An event-driven assessment depending on the number of volunteers with symptomatic or moderate/severe Covid-19 will be performed as the primary efficacy analysis.
Novavax Research and Development president Gregory Glenn said: “With a high level of SARS-CoV-2 transmission observed and expected to continue in the UK, we are optimistic that this pivotal Phase III clinical trial will enroll quickly and provide a near-term view of NVX-CoV2373’s efficacy.
“The data from this trial is expected to support regulatory submissions for licensure in the UK, EU and other countries.”
Based on Novavax recombinant protein nanoparticle technology, the Covid-19 vaccine candidate was also subjected to Phase I and Phase II trials.