PLX2853 in Combination With Abiraterone Acetate and Prednisone and in Combination With Olaparib in Subjects With Metastatic Castration-Resistant Prostate Cancer (mCRPC)

NCT04556617 | Terminated Phase 1 Results FDA Drug

• 1 other identifier: PLX124-04
• Study Type: interventional
• Target: 19
• Locations: 2 countries
• Sites: 8

Brief Summary

The purpose of this research study is to evaluate safety, pharmacokinetics, pharmacodynamics and preliminary efficacy of the investigational drug PLX2853 in subjects with Metastatic Castration-Resistant Prostate Cancer (mCRPC)

Conditions

Metastatic Castration-resistant Prostate Cancer

Keywords

PLX2853; Metastatic Castration-resistant Prostate Cancer; Olaparib; Abiraterone Acetate; Adenocarcinoma; Prostate Cancer

Outcome Measures

Primary Outcomes (3)

• Number of Participants With Dose-Limiting Toxicities

  Dose limiting toxicity defined as clinically significant adverse events or laboratory abnormalities occurring during first cycle of study drug administration that are possibly related to study drug and that meet specific criteria defined in the protocol

  From time of first dose of PLX2853 and combination agent(s) through completion of Cycle 1 (21 days)

• Phase 1b (Both Arms): Incidence of TEAEs That Are Related to Treatment

  Treatment-emergent adverse events are those reported after study drug has been administered.

  From time of first dose of PLX2853 and combination agent(s) until 30 days from end of treatment (an average of 103 days)

• Determination of Maximum Tolerated Dose

  To be evaluated in both PLX2853 + AA + pred and PLX2853 + olap group; If DLTs observed in 2 or more subjects the dose will be considered intolerable and MTD will have been reached.

  From time of first dose of PLX2853 and combination agent(s) through completion of Cycle 1 (21 days)

Study Arms (5)

Phase 1b PLX2853 (20 mg) + Olaparib

EXPERIMENTAL

Phase 1b dose escalation

Drug: PLX2853 20 mg; Drug: Olaparib

Phase 1b PLX2853 (40 mg) + Abiraterone Acetate + Prednisone

EXPERIMENTAL

Phase 1b dose escalation

Drug: Abiraterone acetate; Drug: Prednisone; Drug: PLX2853 40 mg

Phase 1b PLX2853 (80 mg) + Abiraterone Acetate + Prednisone

EXPERIMENTAL

Phase 1b dose escalation

Drug: Abiraterone acetate; Drug: Prednisone; Drug: PLX2853 80 mg

Phase 2a PLX2853 (80 mg) + Abiraterone Acetate + Prednisone

EXPERIMENTAL

Phase 2a dose expansion

Drug: Abiraterone acetate; Drug: Prednisone; Drug: PLX2853 80 mg

Phase 1b PLX2853 (40 mg) + Olaparib

EXPERIMENTAL

Phase 1b dose escalation

Drug: Olaparib; Drug: PLX2853 40 mg

Interventions

PLX2853 20 mg DRUG

PLX2853 tablets

Phase 1b PLX2853 (20 mg) + Olaparib

Olaparib DRUG

Olaparib tablets

Phase 1b PLX2853 (20 mg) + Olaparib; Phase 1b PLX2853 (40 mg) + Olaparib

Abiraterone acetate DRUG

Abiraterone acetate tablets

Phase 1b PLX2853 (40 mg) + Abiraterone Acetate + Prednisone; Phase 1b PLX2853 (80 mg) + Abiraterone Acetate + Prednisone; Phase 2a PLX2853 (80 mg) + Abiraterone Acetate + Prednisone

Prednisone DRUG

Prednisone (or equivalent) tablets

Phase 1b PLX2853 (40 mg) + Abiraterone Acetate + Prednisone; Phase 1b PLX2853 (80 mg) + Abiraterone Acetate + Prednisone; Phase 2a PLX2853 (80 mg) + Abiraterone Acetate + Prednisone

PLX2853 40 mg DRUG

PLX2853 tablets

Phase 1b PLX2853 (40 mg) + Abiraterone Acetate + Prednisone; Phase 1b PLX2853 (40 mg) + Olaparib

PLX2853 80 mg DRUG

PLX2853 tablets

Phase 1b PLX2853 (80 mg) + Abiraterone Acetate + Prednisone; Phase 2a PLX2853 (80 mg) + Abiraterone Acetate + Prednisone

Eligibility Criteria

• Age: 18 Years+
• Sex: male
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Age ≥18 years at the time of signing informed consent.
• Histologically confirmed adenocarcinoma of the prostate with tumor tissue available for molecular analyses.
• Eastern Cooperative Oncology Group Performance Status 0 to 1.
• Adequate organ function as demonstrated following laboratory values.
• Fertile male subjects with female sexual partners must agree to use a highly effective method of birth control during the study and for 90 days after the last dose of study drug.
• Except as specified above for organ function, all drug-related toxicity from previous cancer therapy (including ongoing Abiraterone Acetate + Prednisone therapy if applicable) must be resolved (to Grade ≤1 or baseline per National Cancer Institute Common Terminology Criteria for Adverse Events version 5.0) prior to study treatment administration (Grade 2: alopecia, hot flashes, decreased libido, or neuropathy is allowed).
• Willingness and ability to provide written informed consent prior to any study-related procedures and to comply with all study requirements.

You may not qualify if:

• Prior exposure to a bromodomain inhibitor.
• History of autoimmune hemolytic anemia or autoimmune thrombocytopenia.
• Clinically significant cardiac disease.
• Inability to take oral medication or significant nausea and vomiting, malabsorption, or significant small bowel resection that, in the opinion of the Investigator, would preclude adequate absorption.
• Active known second malignancy with the exception of any of the following:
• Adequately treated basal cell carcinoma or squamous cell carcinoma of the skin.
• Adequately treated Stage I cancer from which the subject is currently in remission and has been in remission for ≥2 years.
• Any other cancer from which the subject has been disease-free for ≥3 years.
• Subject is participating in any other therapeutic clinical study (observational or registry studies are allowed).
• Presence of any other medical, psychological, familial, sociological, or geographic condition potentially hampering compliance with the study protocol or would interfere with the study endpoints or the subject's ability to participate in the study in the judgment of the Investigator.
• Receipt of any anti-cancer therapy prior to Cycle 1 Day 1 with less than protocol defined wash-out with the exception of Abiraterone Acetate (for subjects enrolling into Abiraterone Acetate Combination) and GnRH therapy.

Sponsors & Collaborators

• Opna Bio LLC: lead

Study Sites (8)

University of Chicago

Chicago, Illinois, 60637, United States

Location

Karmanos Cancer Institute

Detroit, Michigan, 48201, United States

Location

Columbia University Medical Center

New York, New York, 10032, United States

Location

Carolina Urologic Research Center

Myrtle Beach, South Carolina, 29572, United States

Location

Tennessee Oncology/ Sarah Cannon

Nashville, Tennessee, 37203, United States

Location

Virginia Cancer Specialist

Fairfax, Virginia, 22031, United States

Location

University of Wisconsin

Madison, Wisconsin, 53792, United States

Location

Sarah Cannon Research Institute

London, W1G 6AD, United Kingdom

Location

MeSH Terms

Conditions

Adenocarcinoma; Prostatic Neoplasms

Interventions

olaparib; Abiraterone Acetate; Prednisone

Condition Hierarchy (Ancestors)

Carcinoma; Neoplasms, Glandular and Epithelial; Neoplasms by Histologic Type; Neoplasms; Genital Neoplasms, Male; Urogenital Neoplasms; Neoplasms by Site; Genital Diseases, Male; Genital Diseases; Urogenital Diseases; Prostatic Diseases; Male Urogenital Diseases

Intervention Hierarchy (Ancestors)

Androstenes; Androstanes; Steroids; Fused-Ring Compounds; Polycyclic Compounds; Pregnadienediols; Pregnadienes; Pregnanes

Results Point of Contact

• Title: Kerry Inokuchi
• Organization: Opna Bio

info@opnabio.com

650-204-4065

Publication Agreements

• PI is Sponsor Employee: No
• Restrictive Agreement: No

Study Design

• Study Type: interventional
• Phase: phase 1
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: September 14, 2020
• First Posted: September 21, 2020
• Study Start: September 21, 2020
• Primary Completion: May 24, 2022
• Study Completion: May 24, 2022
• Last Updated: April 8, 2025
• Results First Posted: April 8, 2025

Record last verified: 2025-04

Locations

GB (1); US (7)