We were familiar with the company ViaCyte through its former identity as NovoCell, when we reported that they'd managed to successfully control diabetes in mice using embryonic stem cells back in 2008.
Last year, they changed their name, but their two-part mission remained the same: first, to create fully functioning beta cells (the specific kind of islet cells that make insulin and amylin) from embryonic stem cells, and then to find a way to combat the process that causes the body to attack its own insulin-producing cells.
At the end of December, JDRF announced a partnership with ViaCyte to support their encapsulated beta cell replacement therapy. We've heard so much about this company that we decided it was time to check in with them.
We recently spoke to Allan Robins, Ph.D., acting CEO of ViaCyte, to find out more about this exciting research and what we can expect to see from them in 2012.
DM) Other companies are working with beta cells to cure diabetes, too. What exactly has ViaCyte accomplished in the last year or so that's so exciting?
AR) ViaCyte is working with embryonic stem cells that have been derived in an ethical way. They've been derived in a clean room, so they are been compliant with FDA clinical trial standards as a product. Over the past several years, we've done two major things: we've learned how to grow embryonic stem cells (ESCs) in large quantities, and we've used them to control the glucose animals. We've done this in more than 2,000 animals, so we're very confident that this works.
One great thing is that for all technical purposes, the cells are immortal. You can grow ESCs in large amounts and they can turn into every type of cell in the human body — including all the hormone cells in the pancreas, in particular the insulin-producing beta cells.
Have you run into any significant obstacles?
Given that ESCs can turn into 200 types cells, we had to figure out how to coax them so that they only turn into the cells we want. You want it to be a homogenous group. You don't want them to turn into other cell types, like skin cells or neural cells. It took us quite some time to find the right conditions for the cells and make sure they were all the same.
Doing literally tens of thousands of experiments and relying on developmental biology, the company has developed a process that has created human embryonic stem cells that are not yet mature, so they don't express insulin, but when you put them in vivo into an animal, they mature, and eventually can control glycemia.
Can you tell us about your results so far in regard to protecting the new cells?
When you're talking about treating type 1 diabetes, you're talking about someone who has an active autoimmune condition. That's usually handled by immuno-suppression drugs, which can have serious side effects. We wanted to try an encapsulation process. We have a process which stops the host (the human) cells from attacking the beta cells. In animal trials, they develop appropriately in these devices, and they produce insulin in a very regulated fashion.
First of all, these folks are talking about using a technology to protect human islets. The only current source is cadavers, so they're very limited in supply and not really a treatment for the masses. Secondly, the coating is alginate. This is derived from various seaweeds and has all the associated problems with something biological with respect to batch to batch variability. Our protective barrier is derived from teflon and has little or no batch to batch variability and will not break down in the body over time, which alginate will do.
How does your device encapsulate and protect the beta cells? What does it look like?
We're not sure what it will look like, but it will be smaller than a credit card and pliable. The device is put in subcutaneously, though we haven't totally settled on a site. We're thinking somewhere on the lower back. These devices would be implanted in an outpatient procedure. It takes some time for the cells to mature in the device, so you would continue monitoring. After some time, the patient's need for insulin would go down, much like with the Edmonton Protocol, which uses islet cell transplants. Although there, because there isn't a device involved, you need lifelong immuno-suppression drugs. Plus, those cells come from cadavers, so there is short supply.
How is the insulin able to get out of your device without the immune system getting in?
It's a flat sheet device. The cells go between two sheets that are more or less a teflon membrane, which is porous. It can let molecules in and out, including insulin, glucagon and glucose. But they are small enough that whole cells can't get in. The cells inside are protected from cells of the immune system. There have been several devices like this made in the past, but nobody has had the appropriate cells to put into the device. The cells would sit in the patient's back, and it would take 2-3 months for the system to mature appropriately.
So the cells you're developing are superior?
If you don't have the right cells to put in the device, it's not going to work. You can think of it as a barrier that protects the host and the cells, but it lets free flow of all the important hormones made by endocrine system. When you transplant our product in vivo, it makes all the cells of the endocrine system, metastatin, gyrelin, insulin. It's remarkably similar to an islet. And so you will have counter-regulation going on as well. In animals with glucose, you never get hypoglycemic overshoots. Hypoglycemia is something that insulin-dependent diabetics worry about a lot. These cells appropriately regulate because they act like a regular pancreatic islet. They sense and react appropriately, both by releasing insulin and by releasing glucagon.
Once the device is implanted, what's the process for the patient? How much monitoring and attention would be required?
The device would potentially be changed every 2-5 years. We're not sure yet. A patient would continue to monitor their blood sugar, but we don't know how long the cells will last in the patient. We know they can last the life of a mouse, which is about a year, but those are the longest studies we can do right now. We're hoping the cells will last multiple years, but they may last even longer. At this point in time, we simply don't know how long. But if a patient were off insulin and monitoring blood glucose twice a week, rather than 4-6 times a day, and not having to give insulin or worry about what they eat or exercise, it's certainly going to be a great benefit to the patient!
What are ViaCyte's plans for 2012?
We spent 2011 developing the scaling. So far this has all been done at a laboratory scale. Now we're focusing on how to reach the really large cell numbers necessary to get to the point of being ready for human clinical trials.
If you use human ESC, you have to show the FDA that your cells don't form tumors in animal studies. So in 2012, we'll be working on definitive per-clinical studies on animal efficacy and safety so that we can send a data package to the FDA. Hopefully we'll get to Phase 1 of clinical trials in the first half of 2013.
What does your relationship with JDRF look like?
JDRF plays a role at multiple levels. Part of it is funding over the next 3 years, mostly on the device side of the project. The funding is milestone-dependent, meaning we have certain milestones that we have to achieve.
JDRF is the biggest patient advocacy group in the world. We hope to build a close relationship with them so that they can help articulate our product to healthcare providers to ensure that it will be covered by insurance companies. We also hope the relationship will help us in discussions with the FDA, building our case that our method is safe and efficacious, so that we can move into human clinical trials.
ViaCyte's work certainly sounds groundbreaking.
It's definitely something to revolutionize the treatment of diabetes. We aim to treat the cause of the disease, rather than the symptoms. This product, having all the hormone-producing cells, makes a lot of difference. It will make more sense than monotherapy.
Thanks, Allan, for sharing how ViaCyte plans to conquer the autoimmune response safely. And it's great to see a bit of competition between companies, which will hopefully lead to an even better solution for patients!