Year 1

ViaCyte is developing a cell therapy for diabetes, which will have a tremendous clinical and societal impact as such a large number of people are afflicted with this disease. The therapy is a combination product comprised of pancreatic progenitor cells transplanted within a device, Encaptra™. A large supply of pancreatic progenitors can be produced with a cell manufacturing process that involves the directed differentiation of human embryonic stem cells (hESC). After transplantation the pancreatic progenitor cells differentiate into functional islets that contain insulin-producing beta cells. Encaptra™ is designed to allow the release of insulin to regulate blood glucose levels while simultaneously protecting the transplanted cells from destruction by the patients’ immune system. The combined product provides a large assurance of safety since cells will be contained and the device is retrievable.

This award is focused on product safety, principally the issue of tumorigenicity. Tumor formation is a particular consideration when using hESCs as cell manufacturing starting material since undifferentiated hESCs form a particular type of tumor, called a teratoma, when transplanted into animal models. Therefore, it is important to demonstrate that at the end of the manufacturing process the cell product is largely devoid of undifferentiated hESC and lacks teratoma potential. ViaCyte has been investigating and establishing standardized assays to measure the presence of hESCs and the potential for teratoma formation. In addition, ViaCyte has previously identified several compounds that appear to preferentially kill undifferentiated hESCs while not affecting the viability of pancreatic progenitors. To ensure that Encaptra™ will be fully effective in containing implanted cells in a patient, ViaCyte is developing various assays to ensure the quality of manufactured devices. These newly developed assays will be incorporated into the manufacturing process and data required by the FDA for product safety will be collected. Successful completion of this project will represent a major advance for stem cell-derived therapies and will specifically contribute to establishing a cell therapy for diabetes.