The search for a safe and efficient COVID-19 vaccine is taking many companies to moths, cannabis and tobacco leaves.
Prominent among them are Kentucky Bioprocessing, Novavax, ZYUS Life Sciences, and Sanofi. There are a host of others as well. So, what are these firms up to?
Kentucky Bioprocessing, Medicago swear by tobacco
A biotech subsidiary of the world's largest cigarette maker British American Tobacco (BAT), the US-based Kentucky Bioprocessing is developing a potential COVID-19 vaccine based on tobacco.
As per the World Health Organisation’s (WHO) draft landscape of COVID-19 candidate vaccines, Kentucky’s vaccine is currently in Phase 1/2 trials, under which it will be tested on 180 healthy volunteers in the US.
So how does the vaccine work? Kentucky Bioprocessing cloned a portion of COVID-19’s genetic sequence and developed a potential antigen (SAR-CoV-2 protein). An antigen is a substance which induces an immune response in the body, mainly by producing antibodies.
This antigen was then injected into tobacco plants. Once the plants were harvested, the antigen was purified and administered as a vaccine.
BAT said it is exploring partnerships with government agencies for the clinical studies of the vaccine. Through collaborations with government and third-party manufacturers, BAT believes it can manufacture between 1-3 million doses per week.
BAT is not alone. Canadian biotech firm, Medicago, backed by tobacco behemoth Phillip Morris, is trying something similar. It is using plant leaves from the tobacco family to produce the SARS-CoV-2 spike protein.
If the vaccine works, it would be a booster for big tobacco companies which are trying to diversify into other businesses or exploring alternative uses of tobacco plants, as use of tobacco is linked to cancer, for some time. One such alternative could be the use of tobacco to develop vaccines.
ZYUS Life Sciences goes for cannabis
Even as countries debate over its legalisation, cannabis may have found one more useful application -- this time, a potential COVID-19 vaccine. Medical cannabis is already being used to treat chronic pain and depression.
Canadian firm ZYUS Life Sciences, which specialises in medical cannabis, has partnered with researchers in the infectious diseases division of the University of Saskatchewan, to develop a potential COVID-19 vaccine. The vaccine candidate uses cannabis plants.
In an interview to Canadian TV channel Global News, Zyus CEO Brent Zettl said that the potential vaccine uses a cannabis plant and a different plant to produce the protein.
“The cannabis side of it really just helped us to sort of determine the best ways to manufacture drugs, going forward,” Zettl said.
It works similar to the vaccine based on tobacco. ZYUS said it has tested and demonstrated that the plant-based SARS-CoV-2 protein is recognised by antibodies in the serum of recovered COVID-19 patients, suggesting that plant-based protein, in this form of vaccine, could provide protection from COVID-19 infection.
Moths are drab brown insects that hang around tube lights and bulbs. They are mostly nocturnal fliers, and are generally considered a pest. The innocuous moths are now being used to develop a COVID-19 vaccine.
Some of the potential COVID-19 vaccines of Novavax and Sanofi are using moth cells as factories to produce the SARS-CoV-2 protein or antigen (usually spike protein).
Analysts say the cells of the Fall armyworm moth allow faster production and better yield of antigens, compared to mammal cells.
How does it work? Researchers infected the cells of a moth with a genetically modified baculovirus, into which they introduced the gene for the target protein, in this case, the spike protein.
After being infected with the baculovirus, the insect cell’s machinery gets into action to produce the target protein or antigen. The use of moth cells isn't being tried for the first time in the development of a COVID-19 vaccine.
Sanofi used the technology for its flu vaccine, the FluBlok vaccine. Sanofi acquired Protein Sciences, which developed the vaccine, for $750 million in 2017. Even HPV (human papillomavirus) vaccines for sexually transmitted infections were developed using moth cells.
Apart from Sanofi and Novavax, Danish firm Expres2ion Biotechnologies, Japanese drugmaker Shionogi and Spanish biotech firm Algenex, among several others, are developing potential COVID-19 vaccines based on moths and insects.