Novavax has started enrolment for the Phase II part of an ongoing Phase I/II clinical trial of its Covid-19 vaccine candidate, NVX-CoV2373.
The Phase II portion, which expands the age range of the Phase I portion by including older adults aged 60-84, is a randomised, placebo-controlled, observer-blinded study.
It will assess the immunogenicity and safety of 5µg and 25µg doses of NVX-CoV2373 with 50µg Matrix-M adjuvant in volunteers aged 18 to 84. Secondary outcomes include preliminary assessment of efficacy.
The study is designed to recruit up to 1,500 healthy participants, with approximately 50% of subjects aged over 60, at up to 40 sites across the US and Australia.
It is supported by the Coalition for Epidemic Preparedness Innovations (CEPI) funding.
Novavax Research and Development president Gregory Glenn said: “We expect this Phase II portion of the trial to expand on the encouraging Phase I safety and immunogenicity data for NVX-CoV2373, and we will now look for robust immune responses in older adults.
“Our Phase III trial of NanoFlu, which we reported in March of 2020, provided us with a deep understanding of the unique needs of older adults, who are particularly vulnerable to Covid-19.”
Interim results from the Phase II trial are expected to be reported in the fourth quarter of this year.
The Phase I portion of the Phase I/II study, performed in Australia, showed that NVX-CoV2373 was generally well-tolerated and triggered antibody responses numerically superior compared to human convalescent sera.
Earlier this month, Novavax launched a Phase IIb clinical trial of its Covid-19 vaccine candidate in South Africa.
The trial, conducted in partnership with Wits University Vaccinology professor Dr Shabir Madhi, is partially supported by a $15m grant from the Bill & Melinda Gates Foundation.
One cohort will investigate efficacy, safety and immunogenicity in around 2,665 healthy adults, while the second cohort will assess safety and immunogenicity in nearly 240 medically stable, HIV-positive adults.