NCT07748988

Brief 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. The study will assess changes in HIF2-regulated gene expression through RNA sequencing of serial tumor biopsies obtained at baseline, during treatment, and at progression. Blood samples will also be collected for future analyses.

Trial Health

63
Monitor

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
12

participants targeted

Target at P25-P50 for early_phase_1

Timeline
18mo left

Started Jul 2029

Geographic Reach
1 country

1 active site

Status
not yet recruiting

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

First Submitted

Initial submission to the registry

July 28, 2026

Completed
9 days until next milestone

First Posted

Study publicly available on registry

August 6, 2026

Completed
2.9 years until next milestone

Study Start

First participant enrolled

July 1, 2029

Expected
1 year until next milestone

Primary Completion

Last participant's last visit for primary outcome

July 1, 2030

6 months until next milestone

Study Completion

Last participant's last visit for all outcomes

January 1, 2031

Last Updated

August 6, 2026

Status Verified

July 1, 2026

Enrollment Period

1 year

First QC Date

July 28, 2026

Last Update Submit

July 31, 2026

Conditions

Keywords

HIF-mediated gene expression

Outcome Measures

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.

    1 year

Secondary Outcomes (2)

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

    1 year

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

    1 year

Study Arms (1)

Casdatifan

EXPERIMENTAL

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.

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
Casdatifan

Eligibility Criteria

Age18 Years - 100 Years
Sexall
Healthy VolunteersNo
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • Signed and dated written informed consent.
  • Male or female ≥ 18 years of age on the day of signing informed consent.
  • Eastern Cooperative Oncology Group (ECOG) performance status of 0-2
  • Histologically confirmed metastatic clear cell renal cell carcinoma (ccRCC)
  • Patients must have received at least one immune oncology (IO) agent and at least one VEGF-targeted therapy (alone or in combination)
  • Measurable tumor burden which can be followed by computed tomography (CT) scan or magnetic resonance imaging (MRI), based on RECIST 1.1 as assessed by the local site investigator
  • At least one metastatic lesion that is amenable to percutaneous biopsy
  • Adequate organ and bone marrow function resulted ≤ 28 days prior to first dose of protocol-indicated treatment:
  • Absolute neutrophil count (ANC) ≥ 1500/µL.
  • Platelets ≥ 100,000/µL.
  • Hemoglobin ≥ 10.0 g/dL or ≥ 6.2 mmol/L.
  • Estimated glomerular filtration rate (eGFR) ≥ 30 mL/min (as calculated by the Cockcroft-Gault Formula or calculated/measured by an alternative established institutional standard consistently applied across participants).
  • Total bilirubin ≤ 1.5 times institutional upper limit of normal (ULN), or direct bilirubin ≤ ULN for participants with total bilirubin \> 1.5 xULN.
  • AST (SGOT) and ALT (SGPT) ≤ 2.5 times institutional upper limit of normal (ULN)
  • 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.
  • +8 more criteria

You may not qualify if:

  • Prior treatment with HIF 2α inhibitors (e.g. belzutifan or related agents)
  • Is currently participating in or within 2 weeks prior to receiving first dose of study treatment in a study of an investigational 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.
  • Known severe hypersensitivity (≥ Grade 3) to any of the excipients of casdatifan.
  • History of myocarditis or pericarditis or other known underlying heart disease that is clinically significant by investigator judgment (for example, cardiomyopathy, congestive heart failure with New York Heart Association \[NYHA\] functional classification III or IV, symptomatic arrhythmia not controlled by medication, unstable angina, history of acute myocardial infarction). History of cerebrovascular accident (including TIA) within the past 6 months (24 weeks) prior to starting study treatment.
  • 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.
  • Inability to swallow study treatment.
  • Contraindications to biopsy (e.g. bleeding diathesis, uncorrectable coagulopathy)

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Vanderbilt University Medical Center

Nashville, Tennessee, 37232, United States

Location

MeSH Terms

Conditions

Carcinoma, Renal Cell

Condition Hierarchy (Ancestors)

AdenocarcinomaCarcinomaNeoplasms, Glandular and EpithelialNeoplasms by Histologic TypeNeoplasmsKidney NeoplasmsUrologic NeoplasmsUrogenital NeoplasmsNeoplasms by SiteFemale Urogenital DiseasesFemale Urogenital Diseases and Pregnancy ComplicationsUrogenital DiseasesKidney DiseasesUrologic DiseasesMale Urogenital Diseases

Study Officials

  • Brian Rini

    Vanderbilt University/Ingram Cancer Center

    PRINCIPAL INVESTIGATOR

Central Study Contacts

Vanderbilt-Ingram Services for Timely Access

CONTACT

Study Design

Study Type
interventional
Phase
early phase 1
Allocation
NA
Masking
NONE
Purpose
TREATMENT
Intervention Model
SINGLE GROUP
Sponsor Type
OTHER
Responsible Party
SPONSOR

Study Record Dates

First Submitted

July 28, 2026

First Posted

August 6, 2026

Study Start (Estimated)

July 1, 2029

Primary Completion (Estimated)

July 1, 2030

Study Completion (Estimated)

January 1, 2031

Last Updated

August 6, 2026

Record last verified: 2026-07

Data Sharing

IPD Sharing
Will not share

Locations