A long-acting GDF15 analog causes robust, sustained weight loss and reduction of food intake in an obese non-human primate model

Abstract

GDF15 is a circulating polypeptide associated with cellular stress, and recently linked to metabolic adaptation. GDF15 has a half-life of approximately 3 hours in and acts at the GFRAL receptor selectively expressed in the area postrema. To characterize the effects of sustained GFRAL agonism on food intake (FI) and body weight (BW), we developed a half-life extended analog of GDF15 (Compound H; CpdH) suitable for reduced dosing frequency and tested its effects in obese cynomolgus monkeys. Animals were treated once weekly for 12 weeks with 0.048, 0.16, or 1.6 mg/Kg of CpdH or with 0.02 mg/Kg of the long-acting GLP-1 analog dulaglutide as a positive control. FI was measured daily and BW was measured biweekly. Mechanism-based longitudinal exposure-response (E-R) modeling was performed to characterize the effects of CpdH and dulaglutide on FI and BW. The integrated novel model accounts for both acute, exposure-dependent effects of treatments to reduce FI and the compensatory changes in energy expenditure (EE) and FI that occur over time in response to weight loss. CpdH had approximately linear, dose-proportional pharmacokinetics with a half-life of {approx}8 days and treatment with CpdH led to dose- and exposure-dependent reductions in FI and BW. The 1.6 mg/Kg CpdH dose reduced mean FI by 57.5% at 1 week and provided sustained FI reductions of 31.5% from weeks 9-12, leading to a peak reduction in BW of 16{+/-}5%. Dulaglutide had more modest effects on FI (reductions between 15-40%) and peak BW loss was 3.8{+/-}4.0%. Longitudinal modeling of both the FI and BW profiles suggested reductions in BW observed with both CpdH and dulaglutide were fully explained by the exposure-dependent reductions in FI without any increase in EE. Upon verification of pharmacokinetic/pharmacodynamic relationship established in monkeys and human for dulaglutide, we predicted that CpdH could reach double digit BW loss in human. In summary, treatment with a long-acting GDF15 analog led to sustained dose- and exposure-dependent reductions in food intake in a monkey model of obesity and holds potential for effective clinical obesity pharmacotherapy. Significance StatementGDF15 activation of GFRAL receptors in the hindbrain controls food intake and body weight. Here we describe the effect and durability of a circulating half-life extended analog of GDF15 (Compound H) on food intake and body weight loss in a spontaneously obese cynomolgus monkey model. Inclusion of a translational treatment arm with a weight loss agent, dulaglutide, permitted pharmacokinetic/pharmacodynamic modeling and comparison of both GDF15 and GLP-1 based weight loss mechanisms, and development of an allometric scaling based mathematical model to estimate the efficacy of Compound H in human obese subjects.