Researchers, companies, and academic institutions around the world are working on a vaccine for COVID-19 and Canadians are well-positioned to be among the leaders. One of those companies is the Edmonton startup Entos Pharmaceuticals
. They are developing a DNA vaccine for SARS-CoV-2 and using their platform to deliver it.
A Better Drug Delivery System
The platform, known as Fusogenix, builds off an existing drug delivery technology: lipid nanoparticles (LNPs) that can fuse with cell membranes.
According to John Lewis, CEO of Entos, the problem with existing LNPs is that they use positively-charged lipids which—although functional—are quite toxic at higher doses. Fusogenix, however, uses viral fusogenic proteins, which avoids the toxicity issues associated with existing LNPs.
“We’ve done extensive studies in rats, in dogs, and non-human primates up to what we think is about 25 times the maximum effective human dose,” said Lewis. “We see no toxicity that we might typically see in other [fusogenic lipid] platforms.”
A Genetic Payload
Most vaccines introduce antigens, antigen fragments, or weakened pathogens to elicit an immune response. DNA vaccines offer another way to create this same response by giving the cell the instructions to produce those antigen fragments itself.
Thanks to the relatively low cost of DNA synthesis and sequencing, this would be much easier to scale up than more traditional vaccines. Lewis says that the flexibility of DNA synthesis means that Entos can test 30 different DNA candidates in a little as two weeks.
The federal government is now fast-tracking vaccine clinical trials
to help expedite R&D. If approved, Lewis is confident that production could be ramped up quickly.
“We could produce a million doses in a week,” he said. “It’s just building the facilities to be able to handle that. But the technology itself does not have limitations that would prevent us from doing so.”
Until such a vaccine is released, physical distancing and good hygienic practices are our best tools to minimize the burden on our healthcare systems.