Rezolute reported that its phase 3 Uplift study of ersodetug in tumor hyperinsulinism, or tHI, met its primary endpoint, giving the biotech a late-stage win as it heads toward a separate regulatory discussion with the FDA on congenital HI, or cHI.
Ersodetug is an antibody that binds allosterically to the insulin receptor and is being developed in both tHI and cHI. That two-indication setup matters because the cHI program is further along, but its phase 3 trial missed the primary endpoint, leading the FDA to advise Rezolute to meet with staff before filing for approval in that indication.
The Data
The Uplift study required at least nine of 16 patients to achieve a 50% or greater reduction from baseline in the glucose infusion rate. Rezolute said 13 patients have met that responder criterion to date, enough to hit the trial’s primary endpoint.
Patients had to be on intravenous glucose infusion or parenteral nutrition for at least seven days to enroll. Twelve patients completely discontinued IV glucose. Three participants remain in the pivotal period of the trial, including two who have not yet met the responder criterion.
As previously reported, one patient dropped out of the study early and died one week later of cancer progression. Rezolute said no drug-related safety findings were attributed to ersodetug.
Why It Matters
The immediate signal is that ersodetug’s case appears cleaner in tHI than in cHI. Earlier this year, Rezolute had disclosed that seven of the first eight enrolled patients responded, meaning only two of the remaining eight patients needed to meet the threshold for success. The final topline now converts that early momentum into a completed primary-endpoint win.
The broader implication is strategic rather than purely numerical. Guggenheim Securities analysts said in an Oct. 5 note to investors that positive tHI data could help strengthen the case for cHI by providing additional validation of ersodetug’s mechanism of action. That does not erase the missed primary endpoint in cHI, but it gives Rezolute a more supportive dataset to bring into FDA talks planned for the first quarter of next year.
Investors reacted positively, with Rezolute shares opening up 10% at $4.27 in premarket trading Friday from a Thursday closing price of $3.87.
