A small Quebec-based company is experimenting with a faster and cheaper way to make flu vaccines as part of the U.S. government's program to fight biological threats, including pandemics.
The U.S. Defence Department is investing $21 million US in Medicago, a company that is researching how to make flu vaccines with tobacco plants.
During the H1N1 outbreak, Medicago did a test run of producing the experimental vaccine in Australian tobacco plants.
"It took approximately 19 days until we were able to have the first doses of the vaccine," said Medicago's chief scientific officer, Louis Vezina.
In comparison, the traditional approach of growing flu vaccines in eggs took six months.
'Smart to invest'
Speed counts in a pandemic, said influenza specialist Michael Osterholm of the University of Minnesota.
The U.S. is smart to invest in alternative vaccine technology like tobacco plants or other non-egg approaches, Osterholm said.
Tobacco plant vaccine process
Medicago's greenhouse in a suburb of Quebec City is full of flats of tobacco plants in various stages of growth. The plants make flu vaccine through a simple process:
- Leaves are soaked in a liquid that contains genetic material from the flu virus.
- The plant cells download the genetic sequence but it is never integrated into the pollen.
- The plants' cell machinery kicks in to make virus-like particles. On the outside, the particles look like the virus, but the particles are actually empty and harmless.
- Since the virus-like particles resemble real flu viruses, the human immune system is tricked into defending itself.
"What we do, basically, is introduce a genetic sequence into the tobacco plants and then have the tobacco plants grow for a period after they're inoculated," said Andy Sheldon, the company's CEO.
"Then ... we harvest the vaccine from the plant and purify the vaccine."
The greenhouse environment prevents any pollen from getting out.
The world is not prepared to respond quickly to another pandemic, especially one as deadly as H5N1, avian flu, Osterholm said.
"Tobacco plants really holds promise in that regard that we could effectively respond and give us the vaccine well before a major second wave of a pandemic were to emerge," he said.
Canada's flu strategy remains focused on egg-based vaccines. Health Canada said it is aware of Medicago's research but does not have a contract with the company.
"To date, there is no conclusive data to suggest that one vaccine production technique is safer or more effective than the other," Health Canada said in a statement. "Further research and development will expand our knowledge around the use of this new technology."
Medicago is building a large manufacturing facility in North Carolina to grow tobacco plants and produce about 40 million doses of seasonal flu vaccine per year, or 120 million doses of pandemic flu vaccine for the U.S. market, said Sheldon.
In the event of another pandemic, it would be a huge advantage to have vaccines available in a few weeks, said Dr. Michael Gardam, an infectious diseases specialist and medical director of infection prevention and control at Toronto's University Health Network.
"We've got an innovative company that's doing just that and they're moving their manufacturing away from Canada," said Gardam. "That's unfortunate."
Medicago is in clinical trials with an avian flu vaccine and will start seasonal flu trials next year.