Rezolute secured FDA alignment to convert its ongoing upLIFT study of ersodetug in tumor-associated hyperinsulinism into a single‑arm, open‑label pivotal trial with as few as 16 participants, eliminating the previously contemplated randomized, placebo-controlled component. The company expects topline data in the second half of 2026. FDA also agreed that Rezolute’s separate pivotal sunRIZE trial in congenital hyperinsulinism, slated to read out in December 2025, can serve as confirmatory clinical evidence across indications. upLIFT is enrolling in the U.S. and Europe and will dose 9 mg/kg weekly for eight weeks as an add‑on to the standard of care in patients requiring continuous IV glucose. The primary endpoint is the proportion of participants achieving at least a 50% reduction from baseline in glucose infusion rate, with secondary measures including time to GIR discontinuation, hospital discharge, hypoglycemia burden as measured by SMBG and CGM, and quality of life.
The move reflects the FDA’s increasing willingness to tailor evidence frameworks for ultra‑rare, high‑morbidity settings when mechanistic plausibility and real‑world signals exist. Ersodetug, an allosteric insulin receptor antibody designed to inhibit receptor overactivation driven by insulin or IGF-2, addresses a pathophysiology common to insulinomas and certain non-islet cell tumors. Leaning on expanded access experience in more than 10 tumor HI patients and a robust congenital HI dataset to anchor benefit‑risk across related phenotypes reduces development time and cost while maintaining a coherent biological rationale. The tradeoff is the absence of a concurrent control arm, placing more weight on within‑patient baselines, objective physiologic endpoints, and external evidence to establish clinical meaningfulness.
Operationally, the design concentrates enrollment at specialized endocrine/oncology centers that manage severe hypoglycemia necessitating continuous IV glucose, which should sharpen signal detection but further narrows the pool. Sites will require tight coordination across inpatient and outpatient workflows to capture GIR changes, CGM traces, discharge timing, and patient-reported outcomes, underscoring the importance of interoperable EHR extraction and digital endpoint management. CROs and data vendors will shoulder the integration of high‑frequency glucose data and adjudication of hypoglycemia events across devices, while ensuring consistency in GIR quantification and baseline stabilization. For sponsors and regulators, the cross-indication confirmatory strategy underscores a broader shift toward mechanism-based generalization, potentially setting a procedural template for other rare endocrine and paraneoplastic syndromes where randomized controlled trials are impractical.
The clinical impact, if positive, could be immediate for patients who face prolonged hospitalizations, recurrent admissions, or limited options while awaiting tumor resection or in palliative scenarios. A therapy that reliably halves GIR and accelerates discharge would also resonate with hospital operations and payers focused on reducing resource utilization. However, safety management—avoiding overcorrection to hyperglycemia, monitoring immunogenicity, and understanding interaction with concurrent oncologic therapies—will be closely scrutinized, particularly as treatment extends beyond the eight‑week pivotal window.
The key gating event is the sunRIZE readout in congenital HI. Strong efficacy and safety will de-risk the tumor HI pathway; equivocal results could necessitate re-engagement with the FDA on evidentiary sufficiency. For upLIFT, durability of effect, consistency across insulinoma and non‑islet cell tumor subgroups, and clarity of external comparator strategy will drive regulatory confidence. Watch for protocol updates on GIR measurement standards, prespecified responder definitions, CGM device harmonization, and site activation velocity. Parallel engagement with EMA, manufacturing readiness for a chronic antibody in a small but acute‑care‑heavy population, and early health economics modeling around hospital length of stay will signal how quickly Ersodetug could translate from a streamlined trial to practice.
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.
