Medicago and GSK Collaborating on Plant-Based COVID-19 Vaccine
An ancient relative of tobacco is at the heart of a new COVID-19 vaccine under development by Medicago and GSK.
The two biopharmaceutical companies are working together to create a COVID-19 therapy that combines Medicago’s plant-based recombinant Coronavirus Virus-Like Particles (CoVLP) with GSK’s pandemic adjuvant system.
The CoVLPs are grown in nicotiana benthamiana, a plant closely linked to tobacco. The particles grown by Medicago mimic the structure of the virus responsible for COVID-19, which allows them to be recognized by the immune system.
GSK’s adjuvant creates a stronger immune response. As a result, the vaccine could need less of the CoVLP antigen to make the antibodies needed to fight the disease. That would allow the companies to produce more doses of the COVID-19 vaccine to protect more people.
“This agreement paves the way for an innovative vaccine option combining a scalable plant-based antigen technology with an adjuvant that has pandemic dose-sparing capability,” said Thomas Breuer, M.D., chief medical officer of GSK Vaccines. “This technology also shows promise beyond COVID-19 and has the potential to help prevent other infectious diseases.”
Bruce Clark, Ph.D., Medicago’s president and CEO, added that the collaboration “gives us access to a proven adjuvant that could enhance the effectiveness of our candidate vaccine, and also to a depth of scientific experience to support our development effort.”
Plant-Based Vaccine Technology Has Its Advantages
Medicago is based in Quebec City, Canada and has a biomanufacturing plant in Durham. The company is a leader in technology that uses virus-like particles (VLPs) grown in, and extracted from, the leaves of plants to develop protein-based vaccines. Traditional vaccines rely on animal products or live viruses.
VLPs have several advantages over other types of vaccines.
- They’re made to mimic viruses, which allows the body’s immune system to recognize them and create an immune response. But they lack the core genetic material of a virus, so they’re not infectious and can’t replicate.
- Medicago’s technology only requires the genetic sequence of a viral strain, not the live virus. So the company can rapidly crank out a therapy to attack a pandemic infection like COVID-19.
- Vaccine production can be ramped up simply by increasing the number of plants being grown, to support demand.
- Clinical trial data suggest that VLPs can simultaneously activate both antibody and cell responses.
Clinical Trials Begin This Month, New Vaccine Targeted for 2021
Medicago and GSK plan to begin a Phase 1 clinical trial this month. They will gauge the safety and quality of immune response by using three different dosing levels of antigen, combined with GSK’s pandemic adjuvant and with an adjuvant from another company. The vaccine will be administered on a one- and two-dose schedule.
The companies said they hope to make the therapy available in the first half of next year and expect to be able to produce about 100 million doses by the end of 2021. A large-scale manufacturing facility under construction in Quebec City could increase that amount to one billion doses annually by the end of 2023.
Medicago and GSK said they also will consider developing a post-pandemic COVID-19 vaccine candidate, if it’s needed, along with vaccines for other infectious diseases.
Medicago is owned by Mitsubishi Tanabe Pharma and Philip Morris International. The 21-year-old company employs more than 450 people, 150 of whom work at the Durham manufacturing site.
GSK, headquartered in Brentford, UK, is a global healthcare company with around 100,000 employees worldwide. It was formed from the merger of SmithKline Beecham and GlaxoWellcome in 2000.
GSK delivers around two million vaccine doses per day to people living in more than 160 countries, the company said.