Seventy-five percent of patients receiving IV dextrose or total parenteral nutrition in Rezolute’s Expanded Access Program achieved complete discontinuation of that support, a result drawn from only 9 patients but one that carries real weight given how few options exist for refractory hypoglycemia driven by malignant insulinoma and non-islet cell tumors. That figure, presented at the Endocrine Society annual meeting this week, sits alongside a program still working through the fallout from a Phase 3 miss in congenital hyperinsulinism, and the combination makes this a more complicated read than a standard conference highlight would suggest.
The sunRIZE Phase 3 study of ersodetug in congenital hyperinsulinism, a condition with a birth prevalence of roughly 3.5 per 100,000 in European-ancestry populations, did not meet its primary endpoint measuring change from baseline in average weekly hypoglycemia events by self-monitored blood glucose. Rezolute presented a deeper analysis of that data at ENDO, framing it around “meaningful therapeutic benefit,” but the primary endpoint outcome is the clinical reality regulators will weigh. Diazoxide, FDA-approved for congenital HI since 1976, remains the established pharmacologic anchor, with octreotide used off-label, and ersodetug’s path to displacing that standard now depends on how the company and FDA interpret secondary and exploratory measures from sunRIZE.
The tumor HI program is a separate story. The upLIFT Phase 3 study reached 50% enrollment as of early June, with 8 of approximately 16 planned participants enrolled, and interim observations from those patients were described positively ahead of the ENDO presentations. The EAP case series adds real-world texture to that signal. Nine patients is a thin dataset, but patients dependent on IV dextrose infusions for glucose stability represent an extreme clinical burden, and complete discontinuation is a concrete, hard-to-dismiss outcome. The mechanism supports it: ersodetug acts at the insulin receptor itself, downstream of everything from pancreatic secretion to gastrointestinal incretin signaling, which is why Rezolute argues it can work across etiologies.
The natural history posters, using both a meta-analysis and a claims-based methodology to quantify neurologic and health-economic consequences of congenital HI, are groundwork for a payer argument more than a clinical one. The number that actually determines ersodetug’s trajectory from here is the enrollment completion date for upLIFT: a small, fully enrolled Phase 3 with clean primary data in tumor HI would give Rezolute a regulatory path that the sunRIZE outcome did not close, but has complicated.
Jon Napitupulu is Director of Media Relations at The Clinical Trial Vanguard. Jon, a computer data scientist, focuses on the latest clinical trial industry news and trends.
