The New COVID-19 Vaccine Candidate

The 1^st ever plant-based vaccine and the first made in Canada vaccine by Medicago, has been submitted to Health Canada, FDA (Food & Drug Administration), and other agencies for approval to use in protection against COVID-19, by people over the age of 18 years. 

This vaccine candidate has shown positive phase three clinical trial results, with an efficacy of 75.3% and 88.6% against Delta and Gamma variants, respectively. 

A little bit of background on clinical trials. There are three main phases with a fourth phase focusing on monitoring adverse events once the drug becomes available in the market. The first phase is conducted to test the safety of the drug. If positive results are achieved in phase 1 for safety, it moves to phase two. Phase two is where a small number of people participate in further assessment of safety, and to gather information on how the drug behaves in the body of different individuals and to get preliminary data on efficacy (efficacy is how a drug performs under ideal conditions). Lastly, phase three involves a larger number of people in demonstrating the safety and efficacy of the drug.

Yes, Medicago’s vaccine candidate has been generated through their revolutionary plant-based technology! As someone who is intrigued by science, this technology and the science behind their vaccine development process blew my mind! 

HOW CAN PLANTS MAKE VACCINES?

Well, Medicago creates their vaccines in five steps: synthesis, infiltration, incubation, harvest, and purification. 

1. Synthesis: They use their plants as what they call a “bioreactor”, meaning their plants act as vessels to carry out biological reactions. They start with the gene sequence of the virus. They use that sequence to put into their technology which then produces a real biological product with a unique genetic code that the plants can “read”. 
   
2. Infiltration: They then put this biological product containing the code into host bacteria (named: Agrobacterium tumefaciens). They then submerge these plants in a bath which contains the bacteria carrying the biological product with that code. They then use a vacuum that sucks out the air between plant cells and replaces it with the liquid containing the bacteria carrying the code. 
   
3. Incubation: The plants are then transferred to their greenhouse facility to allow for growth. After about 4 days, plants start to produce virus like particles (these are not infective viruses because they no longer have the initial genetic sequence within them. But rather, these are particles that mimic the virus). 
   
4. Harvest: The plant’s leaves produce these particles in bulk which act as the main ingredient of the vaccine. Plant leaves are harvested and put into their solution which extracts the virus like particles. 
   
5. Purification: Lastly, the solution is purified to get the virus like particles and used to create the final vaccines. 

This is definitely some amazing science at display in Canada! You can watch Medicago’s process of vaccine development here. OR read more about Medicago and their revolutionary technology here.

As the year ends, both Aarjavi and I would like to take this opportunity to thank each and every one of you who choose to read our blogs. We wish you all a very Happy New Year! Stay safe and healthy!