Quebec, Canada-based biotech Medicago has started phase 1 clinical trials for its plant-derived COVID-19 vaccine candidate, administering the first doses in healthy human volunteers.
Medicago’s uses Virus-Like Particles (VLPs), rather than animal products or live viruses, to create its products. VLPs mimic the shape and dimensions of a virus, allowing the body to recognise them and create an immune response. Previous clinical trial data suggests that VLPs have a ‘multi-modal’ mechanism of action that works differently to inactivated vaccines, by activating both arms of the immune system – antibody and cell-mediated response.
The company’s COVID-19 vaccine candidate, a recombinant coronavirus VLP (CoVLP), will be tested in a randomised, partially blinded study of 180 normal healthy subjects aged 18-55. It will evaluate three dosages – 3.75, 7.5 or 15 micrograms and the vaccine will be either administered on its own or with an adjuvant in a prime-boost regimen.
Medicago will be evaluating its CoVLP vaccine candidate alongside two adjuvants, separately – GlaxoSmithKline’s proprietary pandemic adjuvant technology and Dynanvax’s CpG 1018. Last week, GSK and Medicago signed a deal to jointly develop and evaluate the CoVLP candidate, with the companies agreeing to share the cost of development and manufacturing, if it proves to be effective in human subjects.
In a pre-clinical study of CoVLP, the candidate demonstrated a high level of neutralising antibodies, following a single dose when administered with an adjuvant. Adjuvants are thought to be particularly useful in pandemic situations, as they can boost immune response and reduce the amount of antigen required per dose, allowing more vaccine doses to be manufactured and distributed.
If all goes to plan, Medicago envisions a large-scale phase 2/3 trial to begin as early as October, and also expects to be able to manufacture around 100 million doses by the end of 2021. Following the completion of Medicago’s large-scale facility in Quebec City in 2023, the company expects to have capacity to produce up to one billion doses of its COVID-19 vaccine annually.
“Creating a sufficient supply of COVID-19 vaccines within the next year is a challenge that will require multiple approaches, with different technologies,” said Dr Bruce Clark, president and chief executive officer of Medicago.
“Our proven plant-based technology is capable of contributing to the collective solution to this public health emergency,” he added.
Medicago has already completed a phase 3 clinical trial of a quadrivalent VLP influenza vaccine candidate and phase 2 clinical trials of a H1N1 pandemic vaccine candidate, both using its plant-based manufacturing technology. The company’s flu vaccine is currently under review with Health Canada, following the completion of a safety and efficacy clinical programme in over 25,000 subjects.