We've been watching ViaCyte for years, as the San Diego company works towards a method of "reprogramming" human stem cells to grow into new insulin-producing cells that would be implanted in the body housed in a tiny device -- effectively, a functional cure.
Note that this area of encapsulation and islet cell regeneration is one that other companies are approaching as well, but ViaCyte is one of the most visible, and oft-praised in its work with JDRF over the years.
Their idea is simple: Regenerating islet cells that are normally within the pancreas, but instead would be placed into an implantable device to grow more cells and dispense insulin as needed to regulate glucose levels. They've been working on a first-gen version dubbed "PEC-Encap" for years, using stem cell-derived pancreatic "progenitor" cells encapsulated into their delivery device known as Encaptra. That's been the device on display at diabetes conferences and JDRF events, raising excitement within our D-Community. But it's still a long ways off.
Fortunately, the company is wary of using "cure" terminology that may overpromise.
But they are making significant progress.
Their human clinical trial results presented at the ADA Scientific Sessions in June 2018 showed two years worth of data indicating that ViaCyte's potential product does, indeed, work. The company also announced a whopping 165 new patents in 2018, and implanted its first human patients with its second-generation product in January of this year.
We talked with ViaCyte CEO Paul Laikind and VP of Communications Eugene Brandon recently about the latest updates and how they hope to expand the scope of their treatment.
(This is all very timely as funding through the California Institute for Regenerative Medicine (CIRM), an organization that has helped fund ViaCyte's work over the years, is potentially up for renewal on the state ballot next year.)
Switching Up Formulas
The company has actually realigned its pipeline of possible products cure as it continues human clinical trials, testing out new versions of its offerings that will basically restore our ability to produce our own insulin again.
After starting initial human trials a couple years back, ViaCyte learned that what it had considered its second-generation model was actually better suited to be released as a first-generation product. So that one, known as "PEC-Direct," is now first up. It would require immuno-suppressant drugs and would be limited to about the 10% of type 1 patients who are at the highest risk for hypoglycemia unawareness and extreme hypos through what's sometimes dubbed "brittle diabetes," and other more severe complications.
The now-second-generation product called "PEC-Encap" would in theory allow ViaCyte to "tone down the foreign body response" -- meaning less reliance on immuno-suppressant drugs -- making it suitable for use among the broader type 1 and even insulin-using type 2 population.
“We started with PEC-Encap because we thought it could be ready out-of-the-box, and if that were the case then we would not need PEC-Direct. But we could have it in our back pocket if needed,” CEO Laikind says. “As we learned, we made some important findings and saw that it would be better to do it differently.”
Laikind explains that what they discovered in the clinic was an aggressive foreign substance respoonse to the device components that didn’t allow the cells to thrive or function properly, so they paused the research trial to study and improve it more before resuming.
Now, ViaCyte is collaborating with a company called W.L. Gore & Associates on a newer, more effective membrane that would coat the Encaptra cell device to counter the foreign substance response in the body. Those PEC-Encap trials will restart in the second half of 2019.
Meanwhile, their PEC-Direct studies have moved forward smoothly. That revised version doesn’t prevent the foreign substance response but basically works around it using engineered ports, which allow for direct vascularization of the cells. While that requires immuno-suppressant drugs, it also works with other organ transplants that high-risk T1s may be going through. They have completed the first study cohort already and the second part is ongoing, looking at dose ranges and different sized devices being implanted in the body. They are also looking at optimizing the device prototype itself, and they’re collecting data.
Laikind says this new data may be ready to present at the ADA Scientific Sessions in June 2020.
Gene Editing and Diabetes
As we covered in Fall 2018, ViaCyte announced a collaboration with international biopharm company CRISPR Therapeutics to use gene editing to supplement islet cell encapsulation, which has the potential to protect the transplanted beta cells from the inevitable immune system attack that normally kills them off. This would, of course, eliminate the need for patients to take immuno-suppressant drugs, which can have major drawbacks and have been a big barrier to cell implantation to date.
The two companies jointly stated: "We believe the combination of regenerative medicine and gene editing has the potential to offer durable, curative therapies to patients in many different diseases, including common chronic disorders like insulin-requiring diabetes."
In some ways, ViaCyte's collaboration with CRISPR expands on the notion of whether we're talking about a "cure" here; ViaCyte's approach has often been referred to as a "functional cure," because it would only replace the missing insulin cells in a PWDs body, but not address the autoimmune roots of the disease. But working together, these two companies can potentially can do both, to pursue a true "biological cure."
"The combined power of this collaboration lies in the expertise from both companies," ViaCyte's Laikind says.
He says the collaboration is still in early stages, but is an exciting first step on the path to creating a stem-cell derived product that can resist immune system attack -- basically by reworking the cells' DNA to evade that attack. They're meeting regularly, even weekly, and progress is already materializing on work for the future, Laikind tells us.
"We think we have a great starting point for it... Our anticipation is we could end up producing multiple cell lines to test head-to-head, not only in animal models but also in the clinic. Building more than one construct into the clinical trials can show which is most effective in giving you the deep innovation."
It's all very exciting, if only in the research phase...
And that's where we have to pause for a breath.
Where There's Hope, There's Hype
ViaCyte may well be our knight in encapsulated armor. Their CEO offers appropriately cautious hope. It’s the media messengers – or at least the headline writers — who often get carried away when talking about anything cure-related... (sigh).
That "hope vs. hype" balance is nothing new for our D-Community, so we trust you all to keep your expectations in check, while appreciating that the research progress from ViaCyte is quite encouraging these days.
As Dr. Jay Skyler lays out in his recent Diabetologica article on the subject, "hype and hope are not mutually exclusive." Thus we leave you with his brilliant list of cautions to keep in mind when reporting on (or reading about) "diabetes breakthroughs":