Fimepinostat, Combination HDAC and Pi3-kinase Inhibitor Tumor-Directed Therapy for Cushing Disease

Fimepinostat, Combination HDAC and Pi3-kinase Inhibitor Tumor-Directed Therapy for Cushing Disease (NCT05971758) is a Phase 2 interventional studying Cushing Disease, sponsored by University of California, Los Angeles. RECRUITING as of the most recent ClinicalTrials.gov update. Talk to your doctor before contacting the trial site.

About This Trial

Supported by the pre-clinical data (summarized in Research Strategy), the investigators propose that Fimepinostat is an ideal candidate drug in the treatment and intervention of patients with Cushing Disease. The investigators propose a pilot, short-term (4 weeks) phase II single-center study to demonstrate the safety and efficacy of Fimepinostat in the treatment of patients with de novo, persistent, and/or recurrent CD recruited at the University of California, Los Angeles. The trial will have a 2-arm design and will simultaneously examine two different doses of Fimepinostat. The study will allow the investigators to determine the efficacy and safety of these doses in the treatment of CD and guide dose selection for subsequent, larger studies. Funding Source - FDA OOPD.

What Stage of Research Is This?

Phase 2 trials evaluate whether a treatment actually works against Cushing Disease and continue monitoring side effects. Phase 2 enrolls larger groups (typically 100–300 patients) and produces the first real efficacy signal. A successful Phase 2 readout is what unlocks the much larger Phase 3 confirmatory trials needed for FDA approval.

This trial is currently recruiting participants. The sponsor has registered the study with ClinicalTrials.gov as actively enrolling, which means new applicants who meet the eligibility criteria can be considered for screening. Trial status can change between updates — confirm current recruiting status with the study contact before traveling for a screening visit.

With a target enrollment of 20 participants, this is a small study — typical of early-phase research, rare-disease trials, or pilot studies designed to generate preliminary signal before a larger study is launched.

Who May Be Eligible (Plain English)

Who May Qualify: - Male and female patients at least 18 years old - Patients with confirmed pituitary origin Cushing syndrome defined as 1, 2\& 3 or 4 \& 5 below: 1. Persistent hypercortisolism defined as a mean of 3 consecutive 24h UFC at baseline assessment ≥ 1.3x ULN 2. Normal or elevated plasma ACTH levels 3. Pituitary adenoma \> 4mm visible on MRI or inferior petrosal sinus sampling (IPSS) central to peripheral ACTH gradient \>2 at baseline and/or \>2 after DDAVP stimulation. 4. Recurrent or persistent CD defined as pathologically confirmed previously resected pituitary ACTH-secreting tumor, and 24 hour UFC \>ULN at least 4 weeks after pituitary surgery. 5. Patients on medical treatment for CD. waiting period after previous treatments will be completed as below before screening: Inhibitors of steroidogenesis (metyrapone, ketoconazole, osilodristat, - Levo-ketoconazole): 2 weeks - SRLs (pasireotide): 2 weeks - Progesterone receptor antagonist (mifepristone): 2 weeks - Dopamine agonists (cabergoline): 4 weeks - CYP3A4 strong inducers or inhibitors: varies between drugs; minimum 5-6 times the half-life of drug Who Should NOT Join This Trial: - Patients with compromised visual fields, or evidence of visual changes within past 6 months - Patients with sellar tumor abutting or compressing the optic chiasm on MRI and normal visual fields - Patients with Cushing's syndrome not due to an ACTH-secreting pituitary tumor - Patients who have undergone major surgery including pituitary surgery within 1 month of screening or who have any major surgical procedures planned across the study period - Patients with serum potassium \< 3.5 mEq/L unless stably controlled on potassium supplementation - Patients with poorly-controlled Diabetes mellitus evidenced by HbA1c levels \>8 - Patients with poorly controlled hypertension (i.e. blood pressure ≥ 160/100 mm Hg) ...See full criteria on ClinicalTrials.gov Always talk to your doctor about whether this trial is right for you.

These are translations of the protocol\'s inclusion and exclusion criteria, simplified for patients and caregivers. The original clinical text appears below. Eligibility is ultimately confirmed by the trial site\'s screening process — this summary is a starting point for a conversation with your doctor, not a final determination.

Original Eligibility Criteria

View original clinical language

Inclusion Criteria: * Male and female patients at least 18 years old * Patients with confirmed pituitary origin Cushing syndrome defined as 1, 2\& 3 or 4 \& 5 below: 1. Persistent hypercortisolism defined as a mean of 3 consecutive 24h UFC at baseline assessment ≥ 1.3x ULN 2. Normal or elevated plasma ACTH levels 3. Pituitary adenoma \> 4mm visible on MRI or inferior petrosal sinus sampling (IPSS) central to peripheral ACTH gradient \>2 at baseline and/or \>2 after DDAVP stimulation. 4. Recurrent or persistent CD defined as pathologically confirmed previously resected pituitary ACTH-secreting tumor, and 24 hour UFC \>ULN at least 4 weeks after pituitary surgery. 5. Patients on medical treatment for CD. Washout periods will be completed as below before screening: Inhibitors of steroidogenesis (metyrapone, ketoconazole, osilodristat, * Levo-ketoconazole): 2 weeks * SRLs (pasireotide): 2 weeks * Progesterone receptor antagonist (mifepristone): 2 weeks * Dopamine agonists (cabergoline): 4 weeks * CYP3A4 strong inducers or inhibitors: varies between drugs; minimum 5-6 times the half-life of drug Exclusion Criteria: * Patients with compromised visual fields, or evidence of visual changes within past 6 months * Patients with sellar tumor abutting or compressing the optic chiasm on MRI and normal visual fields * Patients with Cushing's syndrome not due to an ACTH-secreting pituitary tumor * Patients who have undergone major surgery including pituitary surgery within 1 month of screening or who have any major surgical procedures planned across the study period * Patients with serum potassium \< 3.5 mEq/L unless stably controlled on potassium supplementation * Patients with poorly-controlled Diabetes mellitus evidenced by HbA1c levels \>8 * Patients with poorly controlled hypertension (i.e. blood pressure ≥ 160/100 mm Hg) * Patients who have clinically significant cardiovascular impairment, as evidenced by the presence of bradycardia, ventricular tachycardia, history of myocardial infarction within past year, or any other cardiovascular impairment that may pose significant health risk in view of the investigator. * Patients with liver disease or history of liver disease such as cirrhosis, chronic active hepatitis B and C, or chronic persistent hepatitis, or patients with ALT or AST \>1.5 x ULN, serum total bilirubin \>ULN, serum albumin \<0.67 x LLN at screening * Patients with renal disease or history of renal disease with creatinine clearance of 30 cm3/min or less and/or creatinine \> 1.5 mg/dl at screening * Patients not biochemically euthyroid. Patients receiving thyroid-replacement therapy must be on a stable dose for at least 3 months. * Patients who are known to be positive for HIV, or any other condition that significantly compromises subject's immune system. * History of alcohol abuse or illicit substance use within past year. * Female patients who are pregnant or lactating or are of childbearing potential unless willing to practice acceptable method of birth control. Women participating in the trial must employ double barrier method through oral contraceptive or diaphragm with partner utilizing a condom. Abstinence is an acceptable form of birth control if routinely practiced. Male participants must utilize a condom with spermicidal cap/jelly and agree to not donate sperm for up to 3 months beyond main study period. * Patients who have participated in any clinical investigation with an investigational drug within 1 month prior to screening or within 5 half-lives of the investigational treatment whichever is longer. * Patients with concomitant treatment of strong CYP3A4 inducers or inhibitors. * Patients who have received pituitary irradiation within the last 5 years prior to the baseline visit * Patients with known hepatitis B surface antigen (HbsAg) positivity * Patients with known hepatitis C antibody (anti-HCV) positivity

Treatments Being Tested

DRUG

Fimepinostat

The study will allow us to determine the efficacy and safety of these doses in the treatment of Cushing Disease (CD) and guide dose selection for subsequent, larger studies.

Locations (1)

Trial sites listed on ClinicalTrials.gov for this study. Site activation status can vary — confirm with the specific site before traveling for a screening visit.

Ronald Reagan Medical Center

Los Angeles, California, United States

How to Talk to Your Doctor About This Trial

Bring the printable summary of this trial — including the NCT ID (NCT05971758), the sponsor (University of California, Los Angeles), and the key eligibility criteria — to your next appointment. Your doctor can review the inclusion and exclusion criteria against your medical history, lab values, and current treatments to assess whether you are likely to qualify. They can also help you weigh whether trial participation makes sense alongside your existing care plan.

Useful questions to walk through together: What does the trial protocol require beyond standard care? How long is the active treatment phase, and how long is follow-up? Are there study visits at sites I can reach? Who pays for the trial-specific procedures, and who pays for standard-of-care portions? See our 25 questions to ask about clinical trials guide for a more complete checklist.

Authoritative Sources

The official record for this trial lives on ClinicalTrials.gov — the federal registry maintained by the National Library of Medicine at NIH. For background on how this trial fits into the FDA approval pathway, see the FDA drug approval process. For oncology-specific guidance for patients considering trials, the National Cancer Institute publishes patient-oriented overviews. International trial registries are aggregated by the WHO ICTRP.

Frequently Asked Questions

What is the NCT05971758 clinical trial studying?

Supported by the pre-clinical data (summarized in Research Strategy), the investigators propose that Fimepinostat is an ideal candidate drug in the treatment and intervention of patients with Cushing Disease. The investigators propose a pilot, short-term (4 weeks) phase II single-center study to demonstrate the safety and efficacy of Fimepinostat in the treatment of patients with de novo, persistent, and/or recurrent CD recruited at the University of California, Los Angeles. The trial will have a 2-arm design and will simultaneously examine two different doses of Fimepinostat. The study will a… The full protocol is registered on ClinicalTrials.gov and includes the primary outcome measures, eligibility criteria, and study endpoints.

Who can participate in NCT05971758?

Eligibility for this trial depends on the specific inclusion and exclusion criteria set by the sponsor. The plain-English summary above translates the most important criteria into accessible language; the official clinical text is preserved in the collapsible section underneath. Whether you fit any specific trial is a medical decision your doctor needs to confirm — bring the trial information to your treating physician for a full review against your medical history.

How do I contact the trial site for NCT05971758?

Contact information registered with ClinicalTrials.gov is shown in the sidebar of this page. Before reaching out, confirm with your treating physician that this trial is appropriate for your situation. The trial site will then walk you through the screening process to determine final eligibility.

Is participating in a clinical trial safe?

Clinical trials in the United States are regulated by the FDA and overseen by Institutional Review Boards (IRBs) that review the protocol for safety. Risk varies by trial — Phase 1 studies test new treatments in humans for the first time, while Phase 3 trials use treatments that have already passed earlier safety screening. The informed consent document for any specific trial details the known risks and what to expect. Discuss those risks with your physician before deciding whether to participate.

Where can I verify the data on this page?

Every detail on this page comes directly from the ClinicalTrials.gov API. Click "View on ClinicalTrials.gov" in the sidebar to see the official, unmodified record. The federal record is always authoritative; this page is a structured presentation with a plain-English eligibility translation. For background on how clinical trials are regulated, see the FDA drug approval process documentation.

How This Page Is Built

Every field on this page is pulled directly from the ClinicalTrials.gov API v2 — no estimates, no proxies. The plain-English eligibility translation is generated from the original protocol text and reviewed for fidelity to the underlying clinical criteria. The original clinical text remains visible in the collapsible section above so users and clinicians can verify the translation. Read the full methodology for the data pipeline and known limitations.

Source: ClinicalTrials.gov API v2 record for NCT05971758. Maintained by the National Library of Medicine at NIH. Public domain. Cite as: "TrialFinderData. NCT05971758. Data: ClinicalTrials.gov."

Medical disclaimer: This page is informational, not medical advice. Talk to your doctor about whether a clinical trial is right for you.

Last updated 2026-06-07 · Data from ClinicalTrials.gov.