Stem cell therapies for Type 1 diabetes: current status and proposed road map to guide successful clinical trials

Many people with Type 1 diabetes struggle with the burden of self-management and are unable to achieve optimal glycaemic control without risk of hypoglycaemia. Future therapies with the potential to reduce the risk for short- and long-term complications while simultaneously reducing the burden of diabetes are therefore attractive. β-cell replacement is one strategy which might achieve this. Islet transplantation is limited by organ supply and the risks of long-term immunosuppression. Encapsulated stem-cell-derived β cells have the potential to address both of these issues and phase I/II clinical trials of encapsulated pancreatic progenitors have begun. A significant risk associated with the translation of stem-cell science to the clinical management of Type 1 diabetes is an underestimation of the complexity of the process and a mismatch between the hype and the expectations of both people with Type 1 diabetes and the public. We provide an update on progress in clinical trials of encapsulated stem-cell-derived β cells and propose a road map for the design and conduct of future trials to facilitate the translation of this exciting science to clinical care.

Reduced peripheral activity leading to hepato-preferential action of basal insulin peglispro compared with insulin glargine in patients with type 1 diabetes

AIMS

Basal insulin peglispro (BIL), a novel PEGylated basal insulin with a large hydrodynamic size, has a delayed absorption and reduced clearance that prolongs the duration of action. The current study compared the effects of BIL and insulin glargine (GL) on endogenous glucose production (EGP), glucose disposal rate (GDR) and lipolysis in patients with type 1 diabetes.

MATERIALS AND METHODS

This was a randomized, open-label, four-period, crossover study. Patients received intravenous infusions of BIL and GL, each at two dose levels selected for partial and maximal suppression of EGP, during an 8 to 10 h euglycemic clamp procedure with d-[3-³ H] glucose.

RESULTS

Following correction for equivalent human insulin concentrations (EHIC), low-dose GL infusion resulted in similar EGP at the end of the clamp compared to low-dose BIL infusion (GL/BIL ratio of 1.03) but a higher GDR (GL/BIL ratio of 2.42), indicating similar hepatic activity but attenuated peripheral activity of BIL. Consistent with this, the EHIC-corrected GDR/EGP at the end of the clamp was 1.72-fold greater for GL than BIL following low-dose administration. At the lower dose of BIL and GL (concentrations in the therapeutic range), BIL produced less suppression of lipolysis compared with GL as indicated by free fatty acid and glycerol levels at the end of the clamp.

CONCLUSIONS

Compared with GL, BIL restored the hepato-peripheral insulin action gradient seen in normal physiology via its peripherally restricted action on target tissues related to carbohydrate and lipid metabolism.