insulin-producing beta islet cells in the pancreas. Without insulin, cells throughout the body cannot convert sugar into energy, and people with type 1 diabetes must get an outside source of the hormone, usually from an insulin pump or regular insulin injections.
ViaCyte has engineered human embryonic stem cells to grow inside its implantable packets into pancreatic cells that produce insulin and other hormones needed to maintain normal levels of blood sugar.
The semi-permeable packet enables the full repertoire of pancreatic hormones to pass into the bloodstream while protecting the implanted cells from attack by the immune system. The patient’s immune cells are too big to pass through the packet’s outer membrane.
“Three months after implantation, the cells are surviving, they are proliferating… the device is vascularized, and they are differentiating,” Laikind said. “We can show markers of insulin production in the cells.” (The image at the top of the page shows how ViaCyte’s bio-engineered packet, implanted in mice, became vascularized and human insulin from matured pancreatic cells could be released in the bloodstream.)
Based on the limited data disclosed so far, Kieffer said, “The results support the concept that it is possible to achieve surviving insulin-producing cells from stem cells in a patient with diabetes, notably in the absence of immunosuppression. This means that the device used to contain the cells and placed under the skin is working to some degree in terms of protecting the cells from immune attack.”
The early data also serve as “an important proof of concept that we are able to translate what we saw in mice into humans,” Laikind said, adding that there is still work to do to improve the product.
Once the early stage trial is completed, the next step would be to meet with the data safety monitoring panel overseeing the study, probably in the second half of 2016, Laikind said. The panel would review patient safety during the early stage trial results and ensure the therapeutic effects were real.
Kieffer added that it will be important to see “if larger doses of cells can impact the control of blood glucose levels and thereby reduce, or even eliminate, insulin injections.”
