A phase 3 clinical trial of Rezolute’s ersodetug in tumor hyperinsulinism (tHI) has hit its primary endpoint, boosting the biotech ahead of a potential filing for FDA approval in another indication.
Rezolute is developing ersodetug, an antibody that binds allosterically to the insulin receptor, in tHI and congenital HI (cHI). The cHI program is more advanced. However, with the phase 3 cHI trial missing its primary endpoint, the FDA has advised Rezolute to meet with its staff before filing for approval in the indication.
The case for ersodetug in tHI appears more clear-cut. The phase 3 Uplift study required at least nine of the 16 patients to have a 50% or greater reduction from baseline in the glucose infusion rate. To date, 13 patients have met the responder criterion, hitting the trial’s primary endpoint. Patients needed to have been on intravenous (IV) glucose infusion or parenteral nutrition for at least seven days to join the trial.
Twelve patients completely discontinued IV glucose. Three participants are still in the pivotal period of the trial, including two who have yet to meet the responder criterion. As previously reported, one patient dropped out of the study early and died one week later of cancer progression.
Rezolute's shares opened up 10% at $4.27 in premarket trading Friday from a Thursday closing price of $3.87.
The earlier updates fueled optimism that the trial would meet its primary endpoint, with Guggenheim Securities analysts calling a positive outcome “highly likely” in an Oct. 14 note to investors. Seven of the first eight patients enrolled in the trial responded, Rezolute disclosed earlier this year, meaning only two of the remaining eight patients needed to meet the criterion for the study to hit its primary endpoint.
No drug-related safety findings were attributed to ersodetug, giving Rezolute a dataset to inform talks with the FDA in the first quarter of next year. Positive data in tHI “could help strengthen the case for cHI by providing additional validation” of ersodetug’s mechanism of action, Guggenheim analysts said in an Oct. 5 note to investors.