|Ottawa Hospital Research Institute's John Bell|
Versant Ventures is enthusiastic about the potential for next-gen oncolytic cancer vaccines. And it's putting its money where the science is.
The venture group has come up with an $11.3 million Series A round for Turnstone Biologics, an Ontario-based biotech that is taking an oncolytics platform technology developed by Canadian scientists and ramping up a new program aimed at taking the field a few big steps forward. And Versant--which enjoys working fields far away from the industry's mainstream--is committing another $20 million in a follow-up financing tranche to make sure the biotech can realize its potential.
John Bell at the Ottawa Hospital Research Institute has been given much of the credit for identifying this approach. Working with support from the Fight Against Cancer Innovation Trust and others, Bell has been laboring in this area with Brian Lichty, a professor at McMaster University and now founding chief technology officer at Turnstone, and David Stojdl from Children's Hospital of Eastern Ontario.
They've come up with the foundation tech that makes up what Turnstone calls the Maraba platform, which uses rhabdovirus isolates to penetrate cancer cells and then destroy them, while whipping up a T cell attack on tumors.
That same basic approach was used to guide the development of T-Vec, an oncolytic agent from Amgen ($AMGN) that was approved yesterday as Imlygic. But Turnstone, much like the newly launched Replimune in the U.K., thinks it has a much better shot at developing a more effective cancer drug.
In specific, their drug is systemically administered, which should provide a leg up over T-Vec, which uses a herpes simplex virus and is delivered with an intratumoral injection. T-Vec has a mixed record on the data front, narrowly missing a statistically significant improvement in overall survival in Phase III, which tends to be narrow to begin with in oncology studies.
"T-Vec is better than most expected," says Versant Partner Jerel Davis, who's joining the board at Turnstone. And it provided some key safety evidence that will help the whole field. "Oncolytic vaccines are safe, that was not expected."
The rhabdovirus approach works quite well in cancer cells, says Bell, who traces his work in the field back to a paper he published in 2000.
"These viruses were able to exploit defects commonly found in cancer cells," he says. "They can grow quite well in cancer cells but not healthy cells."
Like T-Vec, they can destroy cells and release antigens that trigger an immune response. But they are also encoding an antigen--initially MAGE A3--that is designed to gain a specific kind of T cell attack. And the coded antigen can be switched out as the company goes after various types of cancer.
"It's the only product we know with both oncolytic activity as well as a direct stimulation of T cells, it has both of those functions," says Davis, who is based in Vancouver. "It spurs the immune system via the spleen. The theory of it is great, but what's really impressive is the (animal) data."
The mouse data were excellent, says Bell, which isn't unusual in cancer research. But what really got him excited was the primate data that followed.
"The immune responses were quite large; 10 to 100 times higher than the immune response than any other test in a primate setting," notes Bell.
The viral drug is already in a Phase I study, with an expansion study slated to begin in the middle of 2016 that can start to gain some early efficacy read outs, says CEO Sammy Farah. The next step will be a combination study with one of the hot PD-1 checkpoint inhibitors--no word yet on which one--to see how it all matches up.