Abstract 15751: Pharmacodynamic Effect of ARO-ANG3, an Investigational RNA Interference Targeting Hepatic Angiopoietin-like Protein 3, in Patients With Hypercholesterolemia

Background: Angiopoietin-like protein 3 (ANGPTL3) regulates triglyceride (TG) and lipoprotein (LP) metabolism by inhibiting liver and endothelial LP lipases and reduces plasma LDL-C. In Phase 1 Study AROANG1001 (NCT03747224), single and multiple doses of RNA interference therapeutic ARO-ANG3 (100, 200, or 300 mg; n=36) in healthy volunteers substantially reduced ANGPTL3, LDL-C, and other LPs (AHA 2019) compared with placebo (n=16). Purpose: We report preliminary results following repeat doses (days 1 and 29) of ARO-ANG3 in patients with heterozygous familial hypercholesterolemia (FH) with elevated LDL-C despite statin therapy and average LDL-C of 130 mg/dL. An additional group (non-FH patients) had LDL-C > 70 mg/dL despite statin therapy. Methods: Seventeen FH patients received open-label, subcutaneous, ARO-ANG3 100 mg (n=6), 200 mg (n=6), or 300 mg (n=5). Nine non-FH, high risk patients with elevated LDL-C not at goal received either 200 mg ARO-ANG3 (n=6) or placebo (n=3) using a randomized double-blind design. Pharmacodynamic markers included serum ANGPTL3, LDL-C, TG, and others. Results: Results are reported as of 04 May 2020. In FH patients, ARO-ANG3 significantly reduced mean ANGPTL3 levels between 62-92% at week 16 in a dose-dependent manner (Table). LDL-C (23-37%) and TG (25-43%) were consistently reduced at all doses (Table). The mean percent reductions in non-FH patients for ANGPTL3 (85%), LDL-C (28%), and TG (29%) were comparable to those in FH patients, despite their initially lower LDL-C at baseline. As of 15 May 2020, there were no drug-related serious or severe adverse events (AEs) or discontinuations and most AEs were mild. The most common AEs reported in subjects receiving ARO-ANG3 were respiratory tract infection (30% of subjects) and injection site AEs (13% of subjects). Conclusions: In FH and non-FH patients, repeat doses of ARO-ANG3 significantly reduced ANGPTL3, LDL-C, and TG, with favorable safety.