Abstract 12092: IMB-1018792, an Investigational Agent Designed to Augment Cardiac Glucose Utlization and Energetics Reduces Cardiac Remodelling and Preserves Cardiac Function in a Model of Pressure Overload-Induced Heart Failure

Introduction: Energetic impairments play a key role in heart failure (HF). Contributors include reduced pyruvate dehydrogenase activity partially uncoupling glycolysis from glucose oxidation, increased dependence on fatty acid (FA) metabolism yielding less ATP than glucose per O 2 molecule consumed, a lower phosphate-to-O 2 ratio, mitochondrial uncoupling and futile cycling of FA intermediates. IMB-1018972 (IMB-101) is a novel investigational agent designed to increase cardiac glucose uptake to promote glucose oxidation (Randle effect) through partial inhibition of FA oxidation enhancing cardiac energetics and mechanical efficiency. Hypotheses: Administration of IMB-101 will: 1) increase cardiac glucose uptake and 2) attenuate LV hypertrophic remodelling and progression of HF resulting from chronic pressure overload. Methods: 1) Cardiac glucose metabolism was evaluated using dynamic 18 F-FDG PET/CT imaging in vivo in fasted normal rats following a subcutaneous dose of IMB-101 or saline. Each animal had 2 randomized sequenced scan sessions (n=16). 2) Male C57BL/6 mice aged 12 weeks underwent transverse aortic constriction (TAC) or sham surgery (n=15) and were treated with IMB-101 (10 mg/kg/day, n=15) or saline (n=15) from day 1 (D1) for 6 weeks by osmotic minipump. Cardiac function was assessed by conscious echocardiography (D1, week 3 and 6). Cardiac fibrosis was measured by Masson’s Trichrome staining. Results: IMB-101 robustly increased in vivo cardiac 18 F-FDG uptake vs saline in rats. In mice subjected to TAC, compared to saline controls, IMB-101 treatment: preserved LV systolic function (fractional shortening 46%±3% vs 34%±3%, at week 6, p<0.05); improved LV relaxation with less prolonged isovolumic relaxation time (32±1 ms vs 36±1 ms, p<0.05); reduced cardiac hypertrophy (LV mass 156±10 mg vs 195±12 mg, p<0.05; and heart:body weight ratio 7.4±0.3 mg/g vs. 9.1±0.5 mg/g, p<0.05); and attenuated cardiac fibrosis (6.6±0.6% vs 10.7±1%, p<0.01). Conclusions: IMB-101 increases cardiac glucose uptake and protects against LV dysfunction, hypertrophic remodelling and interstitial fibrosis after chronic pressure overload.