Rezolute Receives FDA Recommendation for Pre-BLA Meeting for Congenital Hyperinsulinism Treatment

REDWOOD CITY, Calif., Oct. 05, 2026 /CourierPR/ -- Rezolute, Inc., a late-stage ultra-rare disease company, has received a significant recommendation from the U.S. Food and Drug Administration (FDA) to hold a pre-BLA (Biologics License Application) meeting as a precursor to submitting a BLA for treating congenital hyperinsulinism (HI). This development comes after a preliminary review of detailed data from the Phase 3 sunRIZE study of ersodetug, a fully human monoclonal antibody that binds allosterically to the insulin receptor to decrease receptor over-activation.

The sunRIZE study, a Phase 3, multicenter, double-blind, randomized, placebo-controlled safety and efficacy study, demonstrated glycemic improvements but did not meet the primary endpoint because the reductions in hypoglycemia events by finger-stick self-monitored blood glucose (SMBG) were not statistically significant compared to placebo. Although the key secondary endpoint of time in hypoglycemia by continuous glucose monitoring (CGM) was not met in the Week 24 End-of-Treatment evaluable window, consistent and clinically relevant improvements in hypoglycemia were observed for this and multiple other CGM-based hypoglycemia endpoints in both treatment arms.

At a March 2026 Type B meeting with the FDA, the Agency acknowledged the challenges posed by behavioral factors in clinical trials in this patient population, including limitations associated with SMBG-based measures of hypoglycemia. The Agency requested that Rezolute provide the continuous CGM data for its independent review. In June 2026, the company submitted source and analysis datasets, and summary results from a substantial number of pre-specified, post-hoc, and sensitivity analyses.

The FDA has reviewed the data and, despite the trial’s failure to meet the prespecified primary and key secondary endpoints, encouraged Rezolute to request a Type B pre-BLA meeting as a precursor to submitting a BLA for congenital HI. The Agency explicitly did not opine on the approvability of ersodetug for congenital HI and noted that any such determination would only be made as part of an in-depth evaluation of the supporting data during a formal BLA review, as is customary during a BLA process.

Rezolute is also on track to report topline results for the Phase 3 upLIFT study in tumor HI this quarter. The company will evaluate its overall BLA submission strategy for potentially both programs following the announcement of upLIFT study results. The open-label extension (OLE) phase of the study is ongoing, with a continued high retention rate, indicating an ersodetug treatment duration in the sunRIZE study ranging from approximately nine months to well over two years. This, along with continued glycemic control and a notable reduction in the use of background standard of care therapies, potentially indicates continued glycemic and clinical benefit with ersodetug in longer-term use.

Rezolute’s antibody therapy, ersodetug, has been studied in clinical trials and used in real-world cases for the treatment of refractory hypoglycemia due to a variety of causes of HI. The company’s focus is on treating refractory hypoglycemia caused by any form of hyperinsulinism, including congenital HI, tumor HI (insulinoma, non-islet cell tumors), or bariatric/non-bariatric gastrointestinal surgery hypoglycemia.