Rezolute’s stock has crashed after its only pipeline product flopped in a Phase III trial.
In the sunRIZE trial (NCT06208215), ersodetug, a monoclonal antibody (mAb) that binds to the insulin receptor that is being developed as a treatment for hypoglycemia caused by congenital hyperinsulinism, failed to meet its primary or key secondary endpoints.
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After the company broke the news, its stock crashed by 88.75%, from a 10 December close of $10.94 to an 11 December opening of $1.23. There was a very slight increase during the day, with the company’s stock eventually closing at $1.40.
The primary endpoint was the change in the average weekly hypoglycemia events by self-monitored blood glucose. While there was an approximate 45% reduction in hypoglycemia events in the high dose, this was not statistically significant compared to the placebo group, which experienced a 40% improvement.
The key secondary endpoint, which assessed change in average daily percent time in hypoglycemia by continuous glucose monitoring (CGM), saw an approximate 25% reduction in the 10mg cohort, which again was not statistically significant compared to the placebo, which increased by approximately 5%.
The trial investigated two doses of the therapy, 5mg and 10mg, which were administered every other week for six weeks, then once every four weeks for the remainder of the 24-week treatment period.
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By GlobalDataWhile the efficacy targets were not reached, the safety profile of the drug was generally favourable in both the paediatric and adult populations.
Rezolute’s chief medical officer Dr Brian Roberts said: “We are disappointed that the study did not demonstrate significant improvements in glucose-related endpoints relative to placebo, as well as for the patients and families living with congenital hyperinsulinism who urgently need new treatment options.
“At the same time, there are aspects of the results that merit additional investigation, and we are conducting a thorough evaluation to gain a better understanding of the study outcomes, which will inform our path forward.”
Roberts said the company will meet with the US Food and Drug Administration (FDA) under ersodetug’s breakthrough therapy designation to consider next steps for the programme.
The sunRIZE trial was put on a clinical hold by the FDA in 2024, which was lifted in September of the same year.
The trial failure will be yet another blow to congenital hyperinsulinism patients after the FDA refused to approve Zealand Pharma’s dasiglucagon for the treatment and prevention of hypoglycaemia in infants with congenital hyperinsulinism in 2024.
Congenital hyperinsulinism is characterised by unregulated insulin secretion from beta-cells in the pancreas, which leads to severely low blood sugar levels. Currently, the disease is treated using medications such as diazoxide, chlorothiazide, octreotide/lanreotide and digestive enzymes. If medicine fails, surgical intervention will be evaluated, which can include targeted removal of the problematic part of the pancreas, which often leads to the patient developing diabetes.
The drug is also being investigated in the Phase III upLIFT study (NCT06881992) for tumour hyperinsulinism, with topline results expected in the second half of 2026.
