SBIR-STTR Award

The goal of this Phase I SBIR proposal is to develop a cell-based high throughput screen for inhibitors of a novel fructosamine 3-kinase present in the kidney. Dynamis has named this enzyme Amadorase since it phosphorylates fructoselysine, an Amadori product, to produce fructoselysine 3-phosphate (FL3P). FL3P is unstable and decomposes to lysine, inorganic phosphate, and 3-deoxyglucosone (3DG), a highly reactive dicarbonyl sugar. 3DG is a precursor to advanced glycation end products (AGEs), which play a role in the development of diabetic nephropathy, retinopathy, neuropathy, and heart disease. Since Amadorase is responsible for most of the in vivo production of 3DG, it is an exciting new potential therapeutic target for diabetic complications. Dynamis hypothesizes that the reduction of systemic 3DG levels will result in slowing of the development or a reduction in the severity of diabetic complications. Since there are presently no treatments to halt the progression of diabetic complications, any level of reduction obtained is extremely important to the health and well being of diabetics. Dynamis proposes to create a cell-based assay where growth of Amadorase-expressing, lysine auxotrophs of E. coli or yeast is dependent upon Amadorase regenerating lysine from fructoselysine. Inhibitors of Amadorase will thus inhibit cell growth. A scintillation proximity assay (SPA) is proposed as a fallback system. The HTS will be used in a Phase II SBIR to screen combinatorial chemistry libraries for new Amadorase inhibitors. The discovery of potent drug candidates will lead to strategic partnerships with companies capable of conducting Phase I-Ill clinical trials

The goal of this Phase II SBIR proposal is to discover, through high throughput screening (HTS), an orally deliverable drug candidate that inhibits the enzyme fructosamine-3-kinase (F3K). F3K is a promising therapeutic target because of its catalytic role in the production of 3-deoxyglucosone (3DG). 3DG is a highly reactive molecule that induces oxidative stress and is a precursor to the formation of advanced glycation end products (AGEs), both of which contribute to the development of diabetic complications. Dynamis' hypothesis is that inhibition of F3K, and the subsequent reduction of systemic 3DG levels, will reduce the severity of diabetic complications, such as nephropathy, atherosclerosis, retinopathy and, neuropathy. The financial and social value of such a drug is immense because there are no specific treatments for diabetic complications. Dynamis has demonstrated in diabetic rats the feasibility of reducing systemic 3DG levels by inhibiting F3K with a small molecule substrate analog [3]. However, this inhibitor has low bio-availability and a high Ki value making it a poor drug candidate. Thus, Dynamis proposes to screen a chemically diverse 250,000 compound library for inhibitors of human F3K using an assay developed in Phase I. Dynamis will select compounds that inhibit F3K by 50 percent, confirm hits, cull undesirable structures (e.g., reactive, known toxins, bioavailability), determine IC50 values and mechanism of inhibition, prioritize by potency, structural class, and mechanism of inhibition, test cross-reactivity with selected kinases, and measure toxicity and the ability to reduce 3DG in fibroblasts. Dynamis' criteria for success is to discover one or more drug candidates that: inhibit F3K at <10 mu/M and have structural appeal (i.e., bio-available, low potential toxicity). Afterward, under separate funding, these compounds will be further optimized, tested for toxicity, and tested for the ability to reduce systemic 3DG and the ability to reduce the severity of diabetic complications. These studies will yield drug templates amenable to medicinal optimization, which will significantly accelerate the testing of new drugs in humans to delay the development of diabetic complications