Fifty-seven out of 59 sunRIZE completers are still receiving ersodetug in the open-label extension — a retention figure that matters enormously given that the controlled phase of this trial did not achieve statistical significance on its key secondary CGM endpoint at Week 24. That tension between a technically incomplete pivotal dataset and unusually strong real-world persistence defines exactly where ersodetug stands heading into an FDA review that will determine whether CGM-derived signals can substitute for a primary endpoint built around finger-stick self-monitored blood glucose.
The new analyses presented at PES fill in the picture the topline readout left ambiguous. Across both the Full Analysis Set and the more stringent Per Protocol Set, reductions in time spent in hypoglycemia ranged from 50% to 80% compared to placebo at multiple maintenance-phase timepoints — nominally significant, consistently directional, but not hitting the pre-specified Week 24 window that the trial was powered around. That distinction is not a technicality. The FDA’s Type B meeting in March explicitly flagged the primary endpoint’s design as problematic, and the agency’s response — requesting submission of the full dataset for comprehensive evaluation — is a signal that regulators are willing to engage with the totality of evidence rather than apply a rigid statistical gate. That is a meaningful regulatory posture for a rare pediatric disease with no approved molecular therapy.
The OLE data reinforce the mechanistic story. Patients who rolled over from placebo showed clinically significant glycemic improvements once placed on ersodetug, and a substantial subset has since discontinued diazoxide, somatostatin analogs, or tube feeding regimens entirely — moving to ersodetug monotherapy. That reduction in background standard-of-care burden is not a soft endpoint. In congenital hyperinsulinism, diazoxide carries fluid retention and pulmonary hypertension risks; somatostatin analogs require continuous subcutaneous infusion in many pediatric patients. Displacing those therapies is a concrete clinical outcome, and it strengthens the durability argument that the 24-week controlled window alone cannot make.
The single marker to track now is the FDA’s formal response after reviewing the complete submission package — specifically whether the agency accepts CGM time-in-hypoglycemia as a primary basis for approval or requires an additional controlled study. That determination sets the template not just for ersodetug but for every future hyperinsulinism program trying to move past finger-stick-based endpoints in pediatric populations.
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.
