Canadian Made Plant-Based COVID-19 Vaccine By Medicago Shows Positive Phase III Results, High Efficacy Against Delta Variant

Medicago, a Quebec biopharmaceutical company and GlaxoSmithKline announced positive efficacy and safety results from the global Phase 3 study of Medicago’s plant-based COVID-19 vaccine candidate.

The company in a news release said it conducted Phase 3 trials in over 24,000 adults, 18 years and above, across Canada, the United States, United Kingdom, Mexico, Argentina, and Brazil.

The company says the vaccine had 75.3% efficacy against the Delta variant, and 88.6% against the Gamma variant.  No cases of the Alpha, Lambda and Mu variants were observed in the vaccinated group while 12 cases were observed in the placebo group. The Omicron variant was not circulating during the study.

According to the news release, no related serious adverse events were reported and reactogenicity was generally mild to moderate and transient; symptoms lasting on average only 1 to 3 days. The company says the frequency of mild fever was low (<10%), even after the second dose.

Medicago plans to seek regulatory approval from Health Canada soon and has initiated the regulatory filing process for the adjuvanted plant-based COVID-19 vaccine candidate with FDA and MHRA.  Medicago has also initiated Phase 1/2 trial in Japan where it plans to submit for regulatory approval in combination with the Phase 2/3 global study results next spring.

The vaccine candidate is not approved yet by any regulatory authorities.

Medicago says the vaccination regimen calls for two doses (3.75 microgram of antigen in combination with GSK’s pandemic adjuvant) given intramuscularly 21 days apart. The vaccine is stored at 2 °C to 8 °C.

CEO and President at Medicago, Takashi Nagao said in a news release, “This is an incredible moment for Medicago and for novel vaccine platforms. The results of our clinical trials show the power of plant-based vaccine manufacturing technology. If approved, we will be contributing to the world’s fight against the COVID-19 pandemic with the world’s first plant-based vaccine for use in humans.” 

Medicago’s approach takes the leaves of a plant as a bioreactor to produce one of the three spike proteins of the novel coronavirus, the S-spike. The plant is a close relative to tobacco, known as Nicotiana Benthamiana. The plant has a weak immune system which makes it a good host for virus-like particles (VLP). 

VLPs are designed to mimic the native structure of viruses, allowing them to be easily recognized by the immune system. Because the VLPs lack core genetic material, they are non-infectious and unable to replicate.

VLP vaccines developed by other technologies, have traditionally been used worldwide for more than 30 years.

Medicago has been developing its plant-based technology for the past 20 years, using unique technology to produce Virus-Like Particles (VLP) for its protein vaccines.