December 17th is the date Corcept Therapeutics expects an FDA decision on relacorilant for Cushing's syndrome. The once-daily pill blocks cortisol at the spot where the hormone acts on cells, instead of lowering how much the body makes. A yes would give adults with Cushing's syndrome another medicine beside Korlym, Isturisa, Recorlev and Signifor. The FDA turned relacorilant down once, in December 2025, and later published the letter explaining why. That letter is the clearest guide to what the agency will weigh this time and to what a label might ask of patients, including liver blood tests.
Cushing's After Surgery, and Who Is Waiting on the Relacorilant Decision
The Cushing's Support & Research Foundation (CSRF) surveyed 435 people with Cushing's in 38 countries in 2023. Two thirds of them said surgery had put them into remission. About 1 in 8 (12.65%) said their disease had come back or stayed active after surgery that did not work. They are the group most likely to need a medicine. Another 6% had a diagnosis but had not yet had surgery (CSRF 2023 Global Quality of Life Report).
“Sometimes people we know don't recognize us in active Cushing's”
Cushing's Support & Research Foundation, 2023 Global Quality of Life Report, a statement 68.51% of respondents agreed with
The same survey shows what living with Cushing's has meant for work and time. Nearly a third of respondents (31.26%) said they had quit a job because of the illness, and about 1 in 5 waited more than 10 years for a diagnosis. CSRF drew its answers from its own members and partner patient groups, so they reflect people active in patient communities rather than every patient. A peer-reviewed survey of 320 patients in 30 countries found that 88.4% still had symptoms after treatment, most often fatigue (Valassi et al., Endocrine Connections, 2022).
For people whose Cushing's came back or never went away, CSRF keeps a persistent Cushing's resource page for that stage. The foundation also hosts monthly support calls on Zoom for patients, and separate calls for caregivers, listed on its home page.
Relacorilant and Korlym Both Block Cortisol at the Receptor, With One Difference That Matters for Cushing's
Relacorilant is a glucocorticoid receptor antagonist, meaning it sits on the receptor cortisol uses to switch cells on and keeps cortisol from attaching. Korlym (mifepristone), also from Corcept, works the same way and has been approved since 2012. Mifepristone also blocks the progesterone receptor, so Korlym has a boxed warning that it ends pregnancy. Women who could become pregnant need a negative pregnancy test before the first dose (Korlym prescribing information). Corcept describes relacorilant as selective, binding the glucocorticoid receptor but not the body's other hormone receptors (Corcept, June 17, 2026).
Korlym's approval covers high blood sugar caused by Cushing's in adults with type 2 diabetes or glucose intolerance whose surgery failed or was not possible. Isturisa and Recorlev lower the amount of cortisol the adrenal glands make. Signifor is a twice-daily injection approved only for Cushing disease, the form caused by a pituitary tumor (each drug's prescribing information).
Lifyorli is the name relacorilant already carries, approved in March 2026 for platinum-resistant ovarian cancer given with chemotherapy. Its label calls for 150mg on the day before, the day of and the day after each chemotherapy infusion. GRACE, the main Cushing's trial, used daily doses that started at 100mg and rose up to 400mg (Lifyorli prescribing information; Pivonello et al., 2026). Lifyorli's label warns about adrenal insufficiency, meaning too little cortisol effect, and about harm to a developing baby.
What the FDA Said Was Missing From the Relacorilant Evidence for Cushing's Syndrome
On December 30, 2025, the FDA turned down relacorilant because Corcept's 2 main trials did not provide what the agency calls substantial evidence of effectiveness. After a full safety review, the letter also concluded that relacorilant is associated with drug-induced liver injury and judged 4 cases probable (FDA complete response letter, corrected January 28, 2026).
GRACE was the trial that met its main goal. Everyone started on relacorilant for up to 22 weeks. People who responded were then randomly switched to placebo or kept on the drug for 12 more weeks, a design called randomized withdrawal. More of the people moved to placebo lost their blood pressure control, a difference of 34 percentage points (Pivonello et al., Lancet Diabetes & Endocrinology, 2026). The FDA's objection was about who reached that comparison.
- Finished the 22-week open-label phase on relacorilantOf 152 enrolled adults, 95 completed the first phase, in which everyone took the drug. (Pivonello et al., Lancet Diabetes & Endocrinology 2026)
- Met the response criteria and were randomizedOf those, 62 went on to the 12-week comparison, with 30 kept on relacorilant and 32 switched to placebo. (Pivonello et al., 2026)
- Randomized with a blood pressure response, the group the main result rests onWithin that group, 43 people met the high blood pressure response criteria, 21 on relacorilant and 22 on placebo. (Pivonello et al., 2026)
The main GRACE result comes from 43 of the 152 adults who enrolled, about 28%, because the trial first kept only people who finished and responded to relacorilant. The FDA counted the same filter differently and found that 46 of the 102 people with high blood pressure at the start reached the withdrawal phase.
The FDA's letter says 102 GRACE participants started with high blood pressure, 40 left during the first 22 weeks and only 46 reached the placebo comparison. The agency wrote that a group filtered this way likely overestimates how well relacorilant would work in the wider population. It also called the 5.2 mmHg drop in the top blood pressure number over those weeks unreliable, since so much data was missing and nobody was on placebo.
GRADIENT enrolled people whose excess cortisol came from the adrenal glands, including a milder form called autonomous cortisol secretion. It missed its main goal, since the top blood pressure number fell about the same on relacorilant as on placebo (5.8 against 5 mmHg, p=0.77). Corcept later looked only at the 33 participants with Cushing's syndrome and high blood pressure and found a 10.4 mmHg difference. The FDA wrote that after-the-fact analyses of a failed trial can be unreliable, and readings were missing for about a third of those people. When the FDA filled in the missing readings its own way, the difference shrank to 4.9 mmHg and could no longer be told apart from chance.
The liver finding in the FDA's relacorilant letter
None of the participants met Hy's law, the standard marker of severe drug-induced liver injury, according to the letter. Still, the agency judged 4 cases to be probable drug-induced liver injury. In one, the liver enzyme ALT rose to 1,952 units per liter, more than 50 times the upper limit of normal. It kept rising after relacorilant was stopped, which the FDA said does not rule the drug out. The FDA wrote that finding 4 cases among only 303 people exposed was concerning, and that more could appear with wider and longer use.
To fix the application, the FDA asked for new clinical data showing a meaningful benefit. It also asked for a plan to manage liver risk through label warnings, routine monitoring and closer tracking after approval. The letter also said the FDA was open to discussing a controlled trial that measures a combination of signs and symptoms. In the agency's view, relacorilant may have benefit for a broader use than the one Corcept sought.
What Corcept Resubmitted for Relacorilant in June 2026, and What Is Still Unknown
Corcept resubmitted the application on June 17, 2026, with new analyses of data from the original application, which it said the FDA had requested (Corcept, June 17, 2026). On May 27, the company said those analyses had a positive outcome and that its talks with the agency had a "productive tenor" (Corcept, May 27, 2026). Corcept bases the application on GRACE, GRADIENT, a long-term extension study and earlier trials. Corcept says it believes the data show meaningful, lasting improvements without some of the serious side effects of current medicines. It names pregnancy loss, low potassium, uterine thickening, vaginal bleeding, adrenal insufficiency and QT prolongation.
The published GRACE paper reported no cases of adrenal insufficiency, drug-related low potassium or QT prolongation, the heart rhythm delay several current medicines can cause. Corcept funded the study (Pivonello et al., 2026). GRACE enrolled 152 people and followed them for up to 34 weeks.
Relacorilant vs Korlym, Isturisa, Recorlev and Signifor, Check by Check
Each Cushing's medicine label sets its own list of blood tests and heart checks, and the 4 approved labels ask for different things. Trial Friend read the warnings, dosing and monitoring sections of each current label and marked a check only where the label tells prescribers to do it.
Of the 4 Cushing's medicines on this grid, Recorlev and Signifor require liver tests, and the FDA has asked Corcept to propose routine liver monitoring for relacorilant. Korlym is the only one that requires a pregnancy test and the only one whose dose cannot be steered by cortisol levels.
Relacorilant would have a place on this grid only once a Cushing's label exists. How its dose would be judged is still unclear, since it acts at the receptor as Korlym does rather than lowering cortisol. The GRACE paper reported no drug-induced low potassium or drug-induced QT delays, though the FDA's safety review covered all 303 people exposed to relacorilant, not only GRACE.
Cushing's Syndrome Trials Open in the US, Including Mild Autonomous Cortisol Secretion
No relacorilant trial for Cushing's syndrome is enrolling now, and Corcept's long-term extension study (NCT03604198) is active but closed to new patients, according to ClinicalTrials.gov. A Trial Friend search of ClinicalTrials.gov on October 28, 2026 found these and other medicine trials recruiting at US sites. Several focus on mild autonomous cortisol secretion, a milder form of excess cortisol from an adrenal growth.
The Cushing disease trials page lists open studies for the pituitary form, with their sites and eligibility rules. A separate study at UT Southwestern in Dallas (NCT07361874) compares adrenal surgery with semaglutide for mild autonomous cortisol secretion. Sparrow Pharmaceuticals' CAPTAIN-T2D trial (NCT07296484) is testing clofutriben in about 1,500 people with hard-to-control type 2 diabetes and excess cortisol at 61 US sites.
Can You Get Relacorilant for Cushing's Syndrome Before the FDA Decides?
Possibly, through Corcept's compassionate use program, which a doctor has to request on a patient's behalf. Corcept says it considers people with serious conditions who have tried standard treatments without success and cannot join one of its trials, and it does not guarantee access. Physicians can reach the program at access@corcept.com, according to Corcept's compassionate use page.
Longer use is where the FDA's letter said more liver cases could surface, and the long-term extension study is the one place that is being measured now. With 125 participants, it lists December 2026 as its estimated primary completion date, and ClinicalTrials.gov does not say when results will be posted. The outcome will be posted on the relacorilant decision page once it is public.
What People Ask About Relacorilant Before December 17th
What is the PDUFA date for relacorilant in Cushing's syndrome?
Corcept expects a decision by December 17, 2026, the target date set after its June 17, 2026 resubmission. The Trial Friend decision page shows the outcome as soon as it is public.
Is relacorilant the same drug as Lifyorli?
Yes, Lifyorli is relacorilant's brand name for platinum-resistant ovarian cancer, approved in March 2026. Corcept proposed a separate brand name for Cushing's, which the FDA found conditionally acceptable and blacked out in its letter.
Why did the FDA turn down relacorilant the first time?
The FDA said Corcept's evidence did not show that relacorilant works for the proposed Cushing's use. The agency said GRACE's result came from a narrowed-down group of people who had already responded to the drug, and that GRADIENT missed its main goal. It posted the letter, with redactions, in its public database of complete response letters.
Does relacorilant cause liver problems?
The FDA concluded in its December 2025 letter that relacorilant is associated with drug-induced liver injury, judging 4 cases probable, though none met Hy's law. Should relacorilant be approved for Cushing's, its label would set how often liver tests are needed, and the FDA asked Corcept to propose exactly that.
Is relacorilant better than Korlym for Cushing's syndrome?
The 2 drugs have never been tested head to head in a trial. Korlym also blocks the progesterone receptor, which brings its pregnancy warning, and its label reports low potassium in 44% of patients in its Cushing's study. No trial has tested whether relacorilant's narrower action matters in daily life.