Endogenous Cushing’s Syndrome Patients Sought for Phase 3 Trial Testing Relacorilant

Corcept Therapeutics is recruiting participants for its Phase 3 clinical trial evaluating relacorilant as a potential treatment for Cushing’s syndrome-related side effects such as high blood pressure and impaired glucose tolerance.

Also, findings from the study “A Randomized-Withdrawal, Placebo-Controlled, Phase 3 Study to Assess the Efficacy and Safety of Selective Glucocorticoid Receptor Antagonist, Relacorilant, in Patients with Cushing Syndrome (GRACE Study),” were presented at the 2019 Annual Meeting of the Endocrine Society (ENDO), in New Orleans, Louisiana.

In endogenous Cushing’s syndrome there is an “internal” culprit — usually a benign tumor — that makes the body produce too much of the hormone  cortisol. The excessive amount of circulating cortisol can lead to serious problems, such as type 2 diabetes and high blood pressure.

Relacorilant is designed to prevent the effects of excess cortisol by blocking one of its receptors, the glucocorticoid receptor. Results from a Phase 2 trial (NCT02804750) suggest that relacorilant may manage the effects of prolonged cortisol excess in Cushing’s patients faster and without the known side effects of approved medications like Korlym (mifepristone).

Also, the treatment improved glucose tolerance and improved blood pressure in patients, suggesting it could be used to treat those with endogenous Cushing’s syndrome and concurrent type 2 diabetes mellitus, impaired glucose tolerance, and/or uncontrolled high blood pressure (hypertension).

Corcept has now designed the GRACE Phase 3 trial (NCT03697109), a multicenter, double-blind, placebo-controlled, randomized-withdrawal study, to evaluate relacorilant’s safety and effectiveness in these patients.

GRACE will be conducted in two stages. First, all patients will be given oral relacorilant each day for 22 weeks, at doses rising from 100 mg to a maximum of 400 mg.

Those who complete that stage and show improvements in pre-specified parameters of glucose tolerance or hypertension will move into the second, randomized phase of the trial.

Here, they will be randomly assigned to placebo or relacorilant at the same dose they received at the end of the first stage. This new round of treatment will last 12 weeks. Treatment-related adverse events (side effects) also will be assessed for up to 48 weeks (about 11 months) as a main outcome.

Additional primary goals include changes in glucose tolerance and blood pressure between the end of the first and second stages of the study.

Secondary objectives include identifying the proportion of patients achieving a response in glucose tolerance and high blood pressure criteria and the proportion of those who worsened at the end of the first stage, and the changes in quality of life throughout the study.

Researchers plan to enroll 130 people in these U.S. cities: Indianapolis, Indiana; Metairie, Louisiana; Jackson, Mississippi; Albany, New York; Jamaica, New York; Wilmington, North Carolina; Miami, Florida; Summerville, South Carolina; El Paso, Texas; Oklahoma City, Oklahoma, and; Aurora, Colorado. More detailed information is available here.

“We look forward to presenting new findings concerning cortisol modulation in patients with hypercortisolism,” Joseph K. Belanoff, MD, Corcept’s CEO,  said in a press release.