Global, multi-center, repeat-dose, phase 2 study of RZ358 (ersodetug), an insulin receptor antibody, for congenital hyperinsulinism

Abstract

Hyperinsulinism; Hypoglycemia; Insulin receptor

Hiperinsulinisme; Hipoglucèmia; Receptor d'insulina

Hiperinsulinismo; Hipoglucemia; Receptor de insulina

Background: Congenital hyperinsulinism (cHI) is a rare, primarily pediatric disease characterized by dysregulated insulin secretion resulting in severe, persistent hypoglycemia, frequently leading to lifelong neurologic impairments. The safety, pharmacokinetics, and glycemic efficacy of ersodetug, a fully human monoclonal antibody that allosterically and reversibly binds the insulin receptor (INSR) and reduces excess insulin action, are being evaluated for the treatment of cHI-related hypoglycemia. Methods: A global, open-label, phase 2b study (ClinicalTrials.gov: NCT04538989) was conducted in 23 patients with cHI with persistent hypoglycemia on standard-of-care (SOC) therapies. Eligible participants (age ≥2 years) received add-on ersodetug at dose levels between 3 and 9 mg/kg intravenously (i.v.) bi-weekly for 8 weeks in 4 sequential dose cohorts. Findings: Enrolled participants (average age = 6.7 years) on SOC (87% medications; 17% previous pancreatectomy) experienced 13 events/week and 23% time in hypoglycemia at baseline. Ersodetug resulted in predictable, dose-proportional pharmacokinetics. No deaths, adverse drug reactions, study withdrawals, or dose-limiting toxicities occurred. Hypoglycemia (<70 mg/dL) events (self-monitored blood glucose) and time (continuous glucose monitoring) improved from baseline by medians of 59% (p < 0.001) and 54% (p < 0.001), respectively, across pooled dose levels and by 48%-84% (events) and 61%-65% (time) at doses of 6 or 9 mg/kg (p < 0.05) with a nearly universal individual patient response rate. Additional hypoglycemia metrics, including overnight hypoglycemia, similarly improved. Conclusion: Ersodetug was generally well tolerated and significantly improved hypoglycemia in participants with cHI. Ersodetug represents a novel INSR-targeted mechanism of action with the potential to be an effective therapy for all forms of cHI, alone or in combination with other therapies.

Rezolute, Inc. (Redwood City, CA), provided funds.