Project Summary: Over 1.5 million Americans suffer from type 1 diabetes (T1D), an autoimmune disorder involving insulin, a hormone that is essential for blood glucose regulation and overall energy metabolism. When first diagnosed with T1D, it is estimated that the patient’s insulin has been reduced by 70-90%. By this point, the immune system has already targeted and destroyed a vast majority of insulin-producing beta cells found in islets of Langerhans within the pancreas. This destruction occurs, in large part, through a barrage of pro-inflammatory cytokines triggering cell death. For a century since its discovery, no other substantial therapeutic advancements have occurred outside of insulin therapy to treat T1D. However, recent advancements focused on beta-cell health have resulted in several clinical trials. ASAKE Biotech, in collaboration with investigators at Ohio University, is developing a small-molecule therapeutic that may be able to treat T1D in two important ways. In tests of rodent and human pancreatic islets in a dish, our lead compound MSB-3 protected beta-cells from cytokine-induced cell death and also stimulated these cells to produce and secrete more insulin without depleting insulin reserves. In our phase 1 grant, we collected data in non-obese diabetic (NOD) mice, a mouse model of T1D, to show that giving MSB-3 daily beginning at 12-weeks of age completely blocked any rise in blood glucose and reduced insulitis (a sign of reduced autoimmunity), whereas 60% of naïve control mice developed T1D. Moreover, In NOD mice that already had diabetes (blood glucose >300 mg/dL), daily MSB-3 treatment stabilized blood glucose and even appeared to reverse the disease entirely with no other therapy given at any point in the trial. Despite these promising effects in disease treatment, we are not certain how MSB-3 works. In Aim 1 of this proposal, ASAKE has partnered with one of the leading experts in small- molecule target identification to use photoaffinity chromatography and other techniques to identify the protein target(s) of our lead compound. These data will be used to better inform compound development by medicinal chemistry and to assess effects of new compounds on insulin secretion and beta-cell protection. To advance product development, we will also test several routes of administration including a novel long-acting subcutaneous pellet in Aim 2 and determine pharmacokinetics and pharmacodynamics in Aim 3. As a possible clinical application, Aim 4 will determine whether MSB-3 could be a used as an additive to improve the efficacy of human islet transplantation procedures. If successful, these studies will greatly aid the development of a potential novel product to treat T1D.