A Clinical Study of ONCT-534 in Subjects With Metastatic Castration-resistant Prostate Cancer.

A Phase 1/2 Study of ONCT-534 in Subjects With Metastatic Castration-Resistant Prostate Cancer

A first-in-human clinical trial to test the investigational treatment ONCT-534 in participants with metastatic castration-resistant prostate cancer. The main questions it aims to answer are:

• What are the most tolerable doses of ONCT-534? (Phase 1)
• Does ONCT-534 have anti-tumor activity at tolerable doses? (Phase 2)

This is a dose escalation and expansion study where participants will receive daily oral doses of ONCT-534.

Study Overview

• Status: Terminated
• Conditions: Metastatic Castration-resistant Prostate Cancer
• Intervention / Treatment: Drug: ONCT-534

Detailed Description

This is a Phase 1/2 multi-center study to investigate the safety, tolerability, and anti-tumor acitivity of ONCT-534 in patients with relapsed or refractory metastatic castration-resistant prostate cancer. The study consists of 2 phases: a Phase 1 Dose Escalation and a Phase 2 Dose Expansion.

• During the dose escalation in Phase 1 a group of participants will be assigned a certain dose level. Once the dose level is considered safe, the next group will be assigned a higher dose level. The dose level may be raised or lowered depending on any safety events that occur throughout Phase 1. There will be approximately 27 participants enrolled in Phase 1. At the end of Phase 1, two dose levels will be chosen to be tested in Phase 2.
• During Phase 2, participants will be randomly assigned to 1 of the 2 dose levels chose in Phase 1. Approximately 16 participants will be enrolled in each of the 2 dose level groups, for a total of 32 participants.

• Study Type: Interventional
• Enrollment (Actual): 21
• Phase: Phase 2; Phase 1

Contacts and Locations

Study Locations

• United Kingdom
  • Surrey
    • Sutton, Surrey, United Kingdom, SM2 5PT
      • The Royal Marsden NHS Trust
• United States
  • California
    • San Francisco, California, United States, 94143
      • University of California San Francisco
  • Michigan
    • Detroit, Michigan, United States, 48201
      • Karmanos Cancer Institute
  • Nebraska
    • Omaha, Nebraska, United States, 68130
      • XCancer Omaha
  • New York
    • New York, New York, United States, 10032
      • Columbia University Medical Center
  • Texas
    • Austin, Texas, United States, 78758
      • NEXT Oncology
    • San Antonio, Texas, United States, 78229
      • NEXT Oncology
  • Virginia
    • Fairfax, Virginia, United States, 22031
      • Next Virginia
  • Washington
    • Seattle, Washington, United States, 98109
      • Fred Hutchinson Cancer Center
  • Wisconsin
    • Madison, Wisconsin, United States, 53792
      • University of Wisconsin Carbone Cancer Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Subject is ≥18 years of age
• Subject has histologically documented metastatic adenocarcinoma of the prostate confirmed by biopsy without neuroendocrine differentiation or small cell features.
• Subjects has a history of metastatic CRPC.
• Subject has R/R disease following treatment with at least one next-generation AR-signaling inhibitor.
• Subject has at least 1 measurable lesion according to Response Evaluation Criteria in Solid Tumors (RECIST) v1.1 criteria or evaluable bony disease. Lesions that have been previously irradiated will be considered measurable only if progression has been documented following completion of radiation therapy.
• Subject has an Eastern Cooperative Oncology Group performance status of 0,1 or 2, and life expectancy of ≥ 6 months.
• Subject agrees to take or continue luteinizing hormone-releasing hormone agonist or antagonist therapy or has undergone bilateral orchiectomy.
• At least 2 weeks or five half-lives have elapsed, whichever is earliest, since last systemic therapy, including taxanes or other chemotherapy. At least one month has elapsed since systemic therapy with radionuclide pharmaceutical agents
• Subject has evidence of disease progression on or after their most recent systemic treatment
• Subject has a PSA level ≥ 10 ng/mL, or ≥ 2 ng/mL and ≥ 50% increase from nadir on prior therapy, whichever is lowest.
• Subject has serum testosterone < 50 ng/dL.
• Subject has adequate renal, hepatic, and pulmonary function
• Subject is committed to practice true abstinence, or use a highly effective method of contraception with any female partner of childbearing potential unless documented to be surgically sterile (i.e., vasectomy or bilateral orchiectomy) and to not make semen donations during the study and for 3 months after the last dose of study drug.

Exclusion Criteria:

• Subject has small cell prostate cancer or neuroendocrine disease histology, including mixed histology.
• Subject has metastases to the brain or central nervous system
• Subject is receiving concurrent anti-cancer therapy (including chemotherapy, antibody therapy, immunotherapy, cellular therapy, or other experimental therapies) except for ongoing androgen inhibiting therapy such as luteinizing hormone-releasing hormone (LHRH) agonists. Supportive non-cancer directed therapies such as bisphosphonates or denosumab are allowed.
• Subjects taking a strong inhibitor of CYP3A4 or a substrate of CYP2C9 or CYP2C19
• Subject had major surgery within 30 days prior to start of study drug.
• Subject has current, untreated pathologic long-bone fractures(s), or risk of imminent pathologic fracture(s).
• Subject has current or imminent spinal cord compression.
• Subject has an active seizure disorder or a history of seizure disorder(s).
• Subject has evidence of active human immunodeficiency virus infection, hepatitis B virus (HBV), or hepatitis C virus (HCV)
• Subject has any other serious illness or medical condition that would interfere with study participation
• Subject has abnormal electrocardiograms (ECGs) that are clinically significant, including average QTcF > 450 ms, or a history of Torsade de Pointes.
• Subject has any infection requiring parenteral antibiotic therapy or causing fever (temperature >100.5°F or 38.1°C) within 1 week prior to first dose.
• Clinically significant other malignancy with the potential to confound study assessments, with the exception of e.g., treated cutaneous squamous cell and basal carcinomas, non-muscle invasive bladder cancer, Rai Stage 0 CLL, and adequately treated Stage 1 to 2 non-cutaneous malignancy in remission for 5 years.
• Subject is unable to comply with the protocol and/or not willing or not available for follow-up assessments
• Subject has any medical intervention or other condition which, in the opinion of the Investigator, could compromise adherence with study requirements or otherwise compromise the study's objectives.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Sequential Assignment
• Masking: None (Open Label)

Number of Arms

8

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Dose Level 1: 40mg QD; 40mg of single agent ONCT-534 to be administered daily in oral tablets	Drug: ONCT-534; ONCT-534 is a dual-action androgen receptor inhibitor (DAARI) with a novel mechanism of action that includes inhibition of AR function and degradation of the AR protein mediated by interaction with the N-terminal domain (NTD) of the AR. ONCT-534 has demonstrated preclinical activity in prostate cancer models against both unmutated androgen receptor (AR), and against multiple forms of AR alteration, including those with AR amplification, mutations in the AR ligand binding domain (LBD), and splice variants with loss of the AR LBD.; Other Names: GTx-534; UT-34
Experimental: Dose Level 2: 80mg QD; 80mg of single agent ONCT-534 to be administered daily in oral tablets	Drug: ONCT-534; ONCT-534 is a dual-action androgen receptor inhibitor (DAARI) with a novel mechanism of action that includes inhibition of AR function and degradation of the AR protein mediated by interaction with the N-terminal domain (NTD) of the AR. ONCT-534 has demonstrated preclinical activity in prostate cancer models against both unmutated androgen receptor (AR), and against multiple forms of AR alteration, including those with AR amplification, mutations in the AR ligand binding domain (LBD), and splice variants with loss of the AR LBD.; Other Names: GTx-534; UT-34
Experimental: Dose Level 3: 160mg QD; 160mg of single agent ONCT-534 to be administered daily in oral tablets	Drug: ONCT-534; ONCT-534 is a dual-action androgen receptor inhibitor (DAARI) with a novel mechanism of action that includes inhibition of AR function and degradation of the AR protein mediated by interaction with the N-terminal domain (NTD) of the AR. ONCT-534 has demonstrated preclinical activity in prostate cancer models against both unmutated androgen receptor (AR), and against multiple forms of AR alteration, including those with AR amplification, mutations in the AR ligand binding domain (LBD), and splice variants with loss of the AR LBD.; Other Names: GTx-534; UT-34
Experimental: Dose Level 4: 300mg QD; 300mg of single agent ONCT-534 to be administered daily in oral tablets	Drug: ONCT-534; ONCT-534 is a dual-action androgen receptor inhibitor (DAARI) with a novel mechanism of action that includes inhibition of AR function and degradation of the AR protein mediated by interaction with the N-terminal domain (NTD) of the AR. ONCT-534 has demonstrated preclinical activity in prostate cancer models against both unmutated androgen receptor (AR), and against multiple forms of AR alteration, including those with AR amplification, mutations in the AR ligand binding domain (LBD), and splice variants with loss of the AR LBD.; Other Names: GTx-534; UT-34
Experimental: Dose Level 5: 600mg QD; 600mg of single agent ONCT-534 to be administered daily in oral tablets	Drug: ONCT-534; ONCT-534 is a dual-action androgen receptor inhibitor (DAARI) with a novel mechanism of action that includes inhibition of AR function and degradation of the AR protein mediated by interaction with the N-terminal domain (NTD) of the AR. ONCT-534 has demonstrated preclinical activity in prostate cancer models against both unmutated androgen receptor (AR), and against multiple forms of AR alteration, including those with AR amplification, mutations in the AR ligand binding domain (LBD), and splice variants with loss of the AR LBD.; Other Names: GTx-534; UT-34
Experimental: Dose Level 6: 1200 mg QD; 1200mg of single agent ONCT-534 to be administered daily in oral tablets	Drug: ONCT-534; ONCT-534 is a dual-action androgen receptor inhibitor (DAARI) with a novel mechanism of action that includes inhibition of AR function and degradation of the AR protein mediated by interaction with the N-terminal domain (NTD) of the AR. ONCT-534 has demonstrated preclinical activity in prostate cancer models against both unmutated androgen receptor (AR), and against multiple forms of AR alteration, including those with AR amplification, mutations in the AR ligand binding domain (LBD), and splice variants with loss of the AR LBD.; Other Names: GTx-534; UT-34
Experimental: BID Dose Level 1: 160 mg BID; 600mg of single agent ONCT-534 to be administered daily in oral tablets	Drug: ONCT-534; ONCT-534 is a dual-action androgen receptor inhibitor (DAARI) with a novel mechanism of action that includes inhibition of AR function and degradation of the AR protein mediated by interaction with the N-terminal domain (NTD) of the AR. ONCT-534 has demonstrated preclinical activity in prostate cancer models against both unmutated androgen receptor (AR), and against multiple forms of AR alteration, including those with AR amplification, mutations in the AR ligand binding domain (LBD), and splice variants with loss of the AR LBD.; Other Names: GTx-534; UT-34
Experimental: BID Dose Level 2: 300 mg BID; 300mg of single agent ONCT-534 to be administered twice daily in oral tablets	Drug: ONCT-534; ONCT-534 is a dual-action androgen receptor inhibitor (DAARI) with a novel mechanism of action that includes inhibition of AR function and degradation of the AR protein mediated by interaction with the N-terminal domain (NTD) of the AR. ONCT-534 has demonstrated preclinical activity in prostate cancer models against both unmutated androgen receptor (AR), and against multiple forms of AR alteration, including those with AR amplification, mutations in the AR ligand binding domain (LBD), and splice variants with loss of the AR LBD.; Other Names: GTx-534; UT-34

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Dose Limiting Toxicities Through Study Day 28	Incidence of DLTs through Study Day 28	Number of Participants with Dose Limiting Toxicities Through Study Day 28

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Reduction of Prostate-Specific Antigen (PSA) by More Than 50%	Proportion of patients who achieve at least a 50% drop in PSA from baseline (PSA50)	Up to 51 Weeks

Collaborators and Investigators

• Sponsor: Oncternal Therapeutics, Inc
• Investigators: Study Director: Salim Yazji, MD, Oncternal Therapeutics

Study record dates

Study Major Dates

• Study Start (Actual): September 20, 2023
• Primary Completion (Actual): September 12, 2024
• Study Completion (Actual): September 12, 2024

Study Registration Dates

• First Submitted: June 7, 2023
• First Submitted That Met QC Criteria: June 15, 2023
• First Posted (Actual): June 23, 2023

Study Record Updates

• Last Update Posted (Estimated): December 11, 2024
• Last Update Submitted That Met QC Criteria: December 9, 2024
• Last Verified: December 1, 2024

More Information

Terms related to this study

• Keywords: Metastatic Prostate Cancer
• Additional Relevant MeSH Terms: Urogenital Diseases; Genital Diseases; Genital Neoplasms, Male; Urogenital Neoplasms; Neoplasms by Site; Neoplasms; Genital Diseases, Male; Prostatic Diseases; Male Urogenital Diseases; Prostatic Neoplasms
• Other Study ID Numbers: ONCT-534-101

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No