ClinicalTrials.gg
RecruitingNCT07748988Updated Sep 25, 2026

Casdatifan for the Treatment of Refractory Metastatic Clear Cell Renal Cell Carcinoma

A Phase 1 interventional study of casdatifan in Refractory Clear Cell Renal Cell Carcinoma and Metastatic Clear Cell Renal Cell Carcinoma, sponsored by Vanderbilt-Ingram Cancer Center. Recruiting at 1 site in United States. Open to participants aged 18 Years to 100 Years. Per ClinicalTrials.gov, last updated 2026-09-25.

Sponsored by Vanderbilt-Ingram Cancer Center · Phase 1, Interventional, and Treatment

From the registry’s dates

  • Started Sep 2026; still recruiting 1 month later.
Updated Sep 25, 2026Now RecruitingSite recruiting status changed+4 moreGo to Updates ↓
Phase
Phase 1
Study type
Interventional
Enrollment
12
Allocation
Not applicable
Ages
18 Years to 100 Years
Sex
All
01

Study summary

This is a single-institution, pilot study of oral casdatifan, a selective HIF-2α inhibitor, in patients with metastatic clear cell renal cell carcinoma refractory to prior IO- and VEGF-based therapies. This phase I trial evaluates the effects of casdatifan on certain genes linked to kidney cancer growth and tests it for the treatment of clear cell renal cell cancer that has not responded to previous treatment (refractory) and that has spread from where it first started (primary site) to other places in the body (metastatic).

Casdatifan may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth.

Read the detailed description

PRIMARY OBJECTIVE:

I. To determine the change in expression of predefined HIF2-regulated target genes in metastatic tumor tissue following casdatifan therapy in a refractory clear cell renal cell carcinoma (ccRCC) population.

SECONDARY OBJECTIVES:

I. To assess changes in global tumor gene expression following casdatifan treatment.

II. To identify differences in baseline and on-treatment HIF-mediated gene expression between objective responders and non-responders.

OUTLINE:

Patients receive casdatifan orally (PO) once daily (QD) on days 1-28 of each cycle. Cycles repeat every 28 days in the absence of disease progression or unacceptable toxicity. Patients undergo computed tomography (CT) or magnetic resonance imaging (MRI), tumor biopsy and blood sample collection throughout the study.

Two dose reductions will be permitted in the event of drug-related adverse events, per protocol-defined criteria:

  • Reduced dose (-1): 50mg once daily
  • Reduced dose (-2): 25mg once daily Treatment will be discontinued if toxicity is not manageable at this reduced dose.

After completion of study treatment, patients who discontinue treatment for reasons other than disease progression are followed up every 12 weeks thereafter.

Casdatifan will be provided by Arcus. No additional therapeutic agents will be administered as part of this protocol.

02

Conditions studied

  • Refractory Clear Cell Renal Cell Carcinoma
  • Metastatic Clear Cell Renal Cell Carcinoma

Keywords

  • HIF-mediated gene expression
03

In context

Carcinoma, Renal Cell

2,037 studies on the registry are indexed under Carcinoma, Renal Cell; 395 are open to participants now.

This study's planned enrollment of 12 is below the median of 43 across 1,564 interventional studies indexed under Carcinoma, Renal Cell.

Browse Carcinoma, Renal Cell studies →

Lead sponsor

Vanderbilt-Ingram Cancer Center is the lead sponsor of 223 studies on the registry; 33 are open to participants now.

Of its 23 completed or terminated interventional studies of FDA-regulated products, 18 (78%) have results posted.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years to 100 Years
Sexes eligible
All
Accepts healthy volunteers
No

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  1. Signed and dated written .
  2. Male or female ≥ 18 years of age on the day of signing informed consent.
  3. (ECOG) performance status of 0-2
  4. confirmed clear cell renal cell carcinoma (ccRCC)
  5. Patients must have received at least one immune oncology (IO) agent and at least one VEGF-targeted therapy (alone or in combination)
  6. Measurable tumor burden which can be followed by computed tomography (CT) scan or magnetic resonance imaging (MRI), based on 1.1 as assessed by the local site investigator
  7. At least one metastatic lesion that is amenable to percutaneous
  8. Adequate organ and bone marrow function resulted ≤ 28 days prior to first dose of protocol-indicated treatment:

    • (ANC) ≥ 1500/µL.
    • ≥ 100,000/µL.
    • ≥ 10.0 g/dL or ≥ 6.2 mmol/L.
    • Estimated (eGFR) ≥ 30 mL/min (as calculated by the Formula or calculated/measured by an alternative established institutional standard consistently applied across participants).
    • Total ≤ 1.5 times institutional (ULN), or direct bilirubin ≤ ULN for participants with total bilirubin > 1.5 xULN.
    • (SGOT) and ALT (SGPT) ≤ 2.5 times institutional upper limit of normal (ULN)
  9. Women must not be breastfeeding and further agree to not breastfeed during study treatment; and for at least 7 days after patient's final dose of casdatifan.
  10. A woman of (WOCBP) - see Appendix 3 for definition of WOCBP - must have a negative serum or urine pregnancy test during screening within 28 days prior to receiving first dose of protocol-indicated treatment, and must agree to follow instructions for using acceptable (Appendix 3) from the time of signing consent, and until at least 7 days after her final dose of casdatifan.
  11. Men must refrain from donating sperm for at least 7 days after patient's final dose of casdatifan.
  12. A man able to father children (see Appendix 3 for definition) who is sexually active with a WOCBP must agree to follow instructions for using acceptable contraception (Appendix 3), from the time of signing consent, and until at least 7 days after his final dose of casdatifan.
  13. No exercise-induced desaturation on a 6-minute walk test, defined as a blood oxygen saturation by pulse oximetry ≤ 88%.
  14. No active pneumonitis at screening as assessed by CT scan.
  15. No medical history of severe (COPD).
  16. If a participant has the participant must meet the following criteria:

    • Participants with previously treated brain metastases may participate provided they are clinically stable and without treatment for at least 14 days prior to the first dose of study treatment. Participants with carcinomatous meningitis are excluded.

Exclusion criteria

Exclusion Criteria:

  1. Prior treatment with HIF 2α inhibitors (e.g. belzutifan or related agents)
  2. Is currently participating in or within 2 weeks prior to receiving first dose of study treatment in a study of an agent or investigational device.

    • Participants who have entered the follow-up phase of an investigational study may participate as long as it has been 2 weeks after the last dose or last exposure to the previous investigational agent or investigational device.
  3. Known severe (≥ Grade 3) to any of the of casdatifan.
  4. History of myocarditis or pericarditis or other known underlying heart disease that is by investigator judgment (for example, cardiomyopathy, congestive heart failure with [NYHA] functional classification III or IV, symptomatic arrhythmia not controlled by medication, unstable angina, history of acute myocardial infarction). History of cerebrovascular accident (including ) within the past 6 months (24 weeks) prior to starting study treatment.
  5. Uncontrolled intercurrent illness including, but not limited to, ongoing or active infection/sepsis, interstitial lung disease, recent hospitalizations with unresolved symptoms, poorly controlled hypertension, or psychiatric illness/social situations that would limit compliance with study requirements.
  6. Inability to swallow study treatment.
  7. to (e.g. bleeding diathesis, uncorrectable coagulopathy)
Terms in these criteria, in plain language(26)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

Informed consent

Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.

You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.

ECOG performance status

A scale of how much an illness limits everyday activity. For people being assessed to join a study, scores run from 0 (fully active) to 4; lower is more active.

0
Fully active, no restrictions.
1
Limited in strenuous activity, but walking and able to do light work, such as housework or office work.
2
Walking and able to look after yourself, but unable to work; up and about more than half of waking hours.
3
Able to look after yourself only in part; in bed or a chair more than half of waking hours.
4
Unable to look after yourself at all; in bed or a chair all day.

Studies most often ask for 0–1 or 0–2. Your doctor gives the score; the WHO scale uses the same steps. The full scale also has 5, which records death.

Histologically or cytologically confirmed

The diagnosis was confirmed by looking at a sample under a microscope: tissue from a biopsy or surgery (histology), or cells from a fluid or needle sample (cytology).

Your pathology report is the document that shows this.

Metastases

Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.

RECIST

The standard rules for measuring tumours on CT or MRI scans, to tell whether a cancer is shrinking, stable or growing during treatment.

“Measurable disease per RECIST 1.1” usually means at least one tumour 10 mm or more at its longest on a CT scan, or a lymph node 15 mm or more across its short axis.

Biopsy and archival tissue

A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.

Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.

Absolute neutrophil count (ANC)

The number of neutrophils, white blood cells that help fight infection, in a given amount of blood. Too few raises the risk of infection.

It is a count, not a percentage of the white cells. Limits are written in units that mean the same: ≥ 1.5 × 10⁹/L is ≥ 1,500 per mm³ (µL). Each lab has its own reference range.

Platelets

Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.

Hemoglobin (Hb)

The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).

GFR and eGFR (kidney filtering)

GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².

Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.

Creatinine clearance (CrCl)

How quickly the kidneys clear creatinine, a waste product, from the blood. A study may estimate it from a blood test with age, weight and sex (often by the Cockcroft–Gault formula), or measure it using blood and urine collected over a set time. Given in mL/min; higher is better.

Bilirubin

A yellow substance made when red blood cells are broken down, which the liver clears. A high level can mean a problem with the liver or the bile ducts.

Criteria often allow more for people with Gilbert’s syndrome, a harmless inherited condition that raises bilirubin.

ULN (upper limit of normal)

The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.

“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.

ALT and AST (liver enzymes)

Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.

Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.

Childbearing potential

Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).

Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.

Contraception

Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.

Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.

COPD

Chronic obstructive pulmonary disease: long-term lung disease that makes it hard to breathe out, including emphysema and chronic bronchitis.

Brain metastases

Cancer deposits in the brain from a cancer that started elsewhere in the body (CNS metastases include the spinal cord).

Studies differ: some leave out any brain metastases, some accept ones treated and stable for some weeks. Check what this study allows.

Corticosteroids (steroids)

Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.

Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.

Investigational drug or device

A drug or device being studied in a clinical trial.

It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.

Hypersensitivity

An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.

Excipients

The other ingredients in a medicine besides the active drug, such as fillers, colours or preservatives.

Clinically significant

Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.

NYHA class (heart failure)

The New York Heart Association’s four classes of how much heart failure limits physical activity.

I
No limits: ordinary activity causes no undue tiredness or breathlessness.
II
Slight limits: comfortable at rest, ordinary activity causes symptoms.
III
Marked limits: comfortable at rest, less than ordinary activity causes symptoms.
IV
Symptoms even at rest; any activity makes them worse.

Studies set their own limit — many outside heart failure leave out class III–IV, while heart failure studies may ask for a particular class. Check the class this study names.

TIA (transient ischaemic attack)

A “mini-stroke”: temporary stroke-like symptoms caused by reduced blood flow to part of the brain, spinal cord or eye, without signs of a new stroke on a scan.

Stroke symptoms need emergency care at once, even if they go away.

Contraindication

A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.

05

Study design

Phase
Phase 1
Primary purpose
Treatment
Allocation
Not applicable
Intervention model
Single group
Masking
None (open label)
Enrollment
12 participants (estimated)

Study arms

  • Experimental
    Casdatifan

    Casdatifan will be taken orally at a fixed dose of 100 mg once daily, with or without food, on a continuous schedule beginning on Cycle 1, Day 1. Cycles repeat every 28 days in the absence of disease progression or unacceptable toxicity. Patients undergo CT scan or MRI, tumor biopsy and blood sample collection throughout the study.

    Drug: casdatifan

Interventions

  • Casdatifan will be taken orally at a fixed dose of 100 mg once daily, with or without food, on a continuous schedule beginning on Cycle 1, Day 1.

    Also known as: AB521, investigational, orally bioavailable small-molecule inhibitor of HIF-2α

06

What researchers measure

Primary outcomes

  1. To determine the change in expression of predefined HIF2-regulated target genes in metastatic tumor tissue following casdatifan therapy in a refractory ccRCC population.

    A serial biopsy design, incorporating biopsies at baseline, on-treatment, and disease progression, enables longitudinal evaluation of the HIF-2α transcriptional program and characterization of adaptive or resistance-associated gene expression changes emerging during therapy.

    Time frame: 1 year (From baseline to on-treatment biopsy)

Secondary outcomes

  1. To assess changes in global tumor gene expression following casdatifan treatment.

    Differential expression of genome-wide transcripts between baseline and on-treatment biopsies.

    Time frame: 1 year (From baseline to on-treatment biopsy)

  2. To identify differences in baseline and on-treatment HIF-mediated gene expression between objective responders and non-responders.

    Comparison of RNA expression profiles stratified by best overall response per RECIST v1.1

    Time frame: 1 year (From baseline to on-treatment biopsy)

07

Study locations

1 of 1 sites recruiting
  • Vanderbilt University Medical Center
    Nashville, Tennessee 37232, United States
    Recruiting
    • Vanderbilt-Ingram Service for Timely Access · Contactcip@vumc.org · 800-811-8480
    • Brian I Rini, MD · Principal investigator
08

References and documents

Individual participant data

Plan to share: No

No publications or documents are linked to this record.

09

Updates

1 registry update since Sep 25, 2026
Status
Not yet recruiting→Recruiting
changed Sep 25, 2026
Sites
Vanderbilt University Medical Center is now Recruiting
Sep 25, 2026
Start date
Jul 1, 2029→Sep 21, 2026 (actual)
Sep 25, 2026
Primary outcomes
1 time frame changed
What changed in the outcomes
  • Time frameTo determine the change in expression of predefined HIF2-regulated target genes in metastatic tumor tissue following casdatifan therapy in a refractory ccRCC population.1 year → 1 year (From baseline to on-treatment biopsy)
Sep 25, 2026
Secondary outcomes
2 time frame changed
What changed in the outcomes
  • Time frameTo assess changes in global tumor gene expression following casdatifan treatment.1 year → 1 year (From baseline to on-treatment biopsy)
  • Time frameTo identify differences in baseline and on-treatment HIF-mediated gene expression between objective responders and non-responders.1 year → 1 year (From baseline to on-treatment biopsy)
Sep 25, 2026
Site contacts
Changed at 1 site. See the sites
Show the site
  • Vanderbilt University Medical Center · Nashville, United StatesContact added c•••@vumc.org · •••8480Contact added (no phone or email listed)
Sep 25, 2026
Title
Pilot Study of Casdatifan-Treated Refractory Renal Cell Carcinoma→Casdatifan for the Treatment of Refractory Metastatic Clear Cell Renal Cell Carcinoma
Sep 25, 2026
Design
Early Phase 1→Phase 1
Sep 25, 2026
Show all 1 update
  1. Sep 25, 2026
    Not yet recruiting→Recruiting
    Vanderbilt University Medical Center is now Recruiting
    Start date Jul 1, 2029→Sep 21, 2026 (now actual)
    Primary outcomes 1 time frame changed
    What changed in the outcomes
    • Time frameTo determine the change in expression of predefined HIF2-regulated target genes in metastatic tumor tissue following casdatifan therapy in a refractory ccRCC population.1 year → 1 year (From baseline to on-treatment biopsy)
    Secondary outcomes 2 time frame changed
    What changed in the outcomes
    • Time frameTo assess changes in global tumor gene expression following casdatifan treatment.1 year → 1 year (From baseline to on-treatment biopsy)
    • Time frameTo identify differences in baseline and on-treatment HIF-mediated gene expression between objective responders and non-responders.1 year → 1 year (From baseline to on-treatment biopsy)
    Design Early Phase 1→Phase 1
    Site contacts Changed at 1 site. See the sites
    Show the site
    • Vanderbilt University Medical Center · Nashville, United StatesContact added c•••@vumc.org · •••8480Contact added (no phone or email listed)
    Title Pilot Study of Casdatifan-Treated Refractory Renal Cell Carcinoma→Casdatifan for the Treatment of Refractory Metastatic Clear Cell Renal Cell Carcinoma
    + 5 other changes: index terms, verification date, description, conditions and arm descriptions

From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗

10

Registry details

Key details

Study ID
NCT07748988
Responsible party
Brian Rini (Assistant Professor of Medicine, Vanderbilt-Ingram Cancer Center) — Principal investigator
First posted
Aug 6, 2026
Start date
Sep 21, 2026
Primary completion
Jul 1, 2030 (estimated)
Completion
Jan 1, 2031 (estimated)
Last update
Sep 25, 2026

Study contacts

Vanderbilt-Ingram Services for Timely Access
Contact
cip@vumc.org
800-811-8480
Brian Rini
principal investigator · Vanderbilt University/Ingram Cancer Center

Oversight

Data monitoring committee
Yes
FDA-regulated drug
Yes
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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