830-P: Preclinical Development of ALN-KHK, an Investigational RNAi Therapeutic for Type 2 Diabetes Mellitus

Abstract

Fructose consumption is implicated in increased rates of metabolic syndrome and type 2 diabetes worldwide. In the liver, ketohexokinase (KHK) is required for fructose metabolism, phosphorylating fructose to fructose-1-phosphate (F1P), a substrate for synthesis of fatty acids, contributing to nonalcoholic fatty liver. Excess liver fat is associated with insulin resistance and loss of glycemic control. Lowering KHK expression should reduce fatty acid synthesis and thus reduce insulin resistance and improve glycemic control in obese individuals with T2DM. We developed a robust RNAi therapeutics platform for delivery of siRNAs to liver using GalNAc conjugates to specifically silence hepatocyte-expressed genes. Liver-directed silencing of KHK improved insulin sensitivity in pre-clinical models of T2DM. ALN-KHK was selected based on in vitro assessment of a large set of GalNAc-siRNAs targeting human and primate KHK. ALN-KHK demonstrated suppression of liver KHK mRNA and protein in cynomolgus macaques after a single subcutaneous (SC) injection with potent and durable reduction in KHK protein (94.1% lowering through day 85 at the 10 mg/kg dose) supporting evaluation of infrequent dosing in the clinic. To evaluate impact of KHK silencing on fructose metabolism and establish circulating biomarkers of pharmacology, cynomolgus macaques were administered an oral fructose bolus on Day 30 following SC injection of ALN-KHK of 0.3, 3 or 10 mg/kg. ALN-KHK treatment resulted in a dose-dependent increase in circulating fructose with a 4.6-fold increase and a 10.7-fold decrease in FGF21 (which is regulated by liver F1P), at 2 hr post fructose bolus, associated with 90.7% KHK liver protein reduction. These data suggest monitoring of circulating fructose and FGF21 to assess KHK silencing in the clinic. In IND-enabling rat and non-human primate toxicology studies ALN-KHK was safe and well tolerated, supporting the planned initiation of first-in-human studies in obese healthy volunteers. Disclosure L. Noetzli: Employee; Alnylam Pharmaceuticals, Inc. Stock/Shareholder; Alnylam Pharmaceuticals, Inc. A. Borodovsky: Employee; Alnylam Pharmaceuticals, Inc. Stock/Shareholder; Alnylam Pharmaceuticals, Inc. X. Chua: Employee; Alnylam Pharmaceuticals, Inc. Stock/Shareholder; Alnylam Pharmaceuticals, Inc. R. Tymon: Employee; Alnylam Pharmaceuticals, Inc. Stock/Shareholder; Alnylam Pharmaceuticals, Inc. J. Darcy: None. S. Belozerova: Employee; Alnylam Pharmaceuticals, Inc. Stock/Shareholder; Alnylam Pharmaceuticals, Inc. M. Keibler: Employee; Alnylam Pharmaceuticals, Inc. Stock/Shareholder; Alnylam Pharmaceuticals, Inc. H. Tu: Employee; Alnylam Pharmaceuticals, Inc. Stock/Shareholder; Alnylam Pharmaceuticals, Inc. E. Maratos-Flier: Employee; Novartis, Alnylam Pharmaceuticals, Inc.