The move comes a month after the vaccine candidate, in combination with the pandemic adjuvant, secured fast track designation from the US Food and Drug Administration (FDA).
Medicago’s vaccine candidate uses a technology called virus-like-particles (VLPs) to mimic the structure of coronavirus.
In the Phase III trial, the vaccine, composed of recombinant spike (S) glycoprotein, will be co-administered with GSK’s pandemic adjuvant on participants in a two dose regimen 21 days apart.
The event-driven, randomised, observer-blinded, placebo-controlled study will evaluate the efficacy and safety of the adjuvanted formulation compared to placebo.
Medicago seeks to enrol up to 30,000 subjects, initially focusing healthy adults and followed by elderly adults (more than 65 years of age) and those with comorbidities.
The company has already received approval from Canadian and US regulatory authorities to commence the enrolment process.
Separately, Medicago started a feasibility study of a vaccine candidate to address the emerging Covid-19 variants.
Medicago president and CEO Takashi Nagao said: “We are pleased to take the significant step of initiating the Phase III clinical trial at sites around the world.
“This brings us one step closer to delivering an important new Covid-19 vaccine and contributing to the global fight against the pandemic along with our partner GSK.”
GSK Vaccines chief medical officer Thomas Breuer said: “This advance to late stage clinical testing further reinforces our confidence in the adjuvanted vaccine candidate’s potential to make a difference in the continued fight against Covid-19. We look forward to sharing results later this year.”
The Phase II portion of the trial is now nearing completion and the results are expected to be published next month.
In a separate development, Cytocom announced that the FDA had cleared the Investigational New Drug (IND) application for a Phase II clinical trial that seeks to assess the efficacy of CYTO-205 in slowing or halting the progression of SARS-CoV-2.