Biomarker-driven Intermittent Docetaxel in Metastatic Castration-resistant Prostate Cancer

Phase 2TerminatedNCT04918810

Australian and New Zealand Urogenital and Prostate Cancer Trials Group6 enrolled

Overview

The purpose of this study is to see if a prostate cancer marker in the blood (mGSTP1) can be used to guide chemotherapy treatment. Based on the level of this blood marker, some people may be able to have breaks in treatment rather than having chemotherapy continuously which is the current standard of care. This study will tell us if having these treatment breaks guided by mGSTP1 can improve how people feel during treatment while still treating the prostate cancer effectively. Docetaxel is a chemotherapy drug that is approved to treat prostate cancer and has been used for many years to treat prostate cancer like yours. Your doctor has already discussed this with you and you have both agreed that docetaxel is the best treatment for you to have at this time. You will have already started this chemotherapeutic treatment with docetaxel.

Study Type

INTERVENTIONAL

Allocation

Purpose

TREATMENT

Masking

NONE

Enrollment

Conditions

Castration Resistant Prostatic Cancer

Interventions

After 3 or 4 cycles of docetaxel chemotherapy (75mg/m\^2 every 21 days or 50mg/m\^2 every 14 days) in combination with an undetectable mGSTP1 level, patients will stop docetaxel treatment. Plasma mGSTP1 is measured every 21 days or 28 days (depending on Docetaxel regimen) and docetaxel treatment will be recommenced if it mGSTP1 becomes detectable again.

Eligibility

Sex: MALEMin age: 18 Years

Medical Language ↔ Plain English

PRESCREENING INCLUSION CRITERIA 1. Patient has provided written informed consent using the GUIDE pre-screening PICF 2. Age ≥ 18 years at the time of pre-screening consent 3. Males with metastatic castration-resistant prostate cancer (as per PCWG3) AND are planned to commence docetaxel chemotherapy 4. WHO Eastern Cooperative Oncology Group (ECOG) performance status 0-2 (Appendix 1) 5. Histological confirmation of prostate cancer 6. Patients must have adequate bone marrow and hepatic function within 14 days prior Cycle 1 day 1: * Haemoglobin ≥ 90 g/L independent of transfusions (no red blood cell transfusion in last 4 weeks) * Platelets ≥ 100 x 109/L * Absolute neutrophil count (ANC) ≥ 1.5 x 109/L * Serum total bilirubin ≤ 1.5 x upper limit of normal (ULN) * Alanine aminotransferase (ALT)/Aspartate aminotransferase (AST) ≤ 2.5 x ULN 7. Willing and able to comply with all pre-screening study requirements, including blood tests for mGSTP1 analysis before and during docetaxel treatment PRESCREENING EXCLUSION CRITERIA 1. Prior docetaxel or cabazitaxel chemotherapy for castration-resistant prostate cancer 2. Prior docetaxel in the castration sensitive prostate cancer setting within the previous 2 years 3. Known hypersensitivity to docetaxel or its excipients 4. Concurrent illness, including severe infection that may jeopardise the ability of the patient to undergo the procedures outlined in this protocol with reasonable safety 5. Serious medical or psychiatric conditions that might limit the ability of the patient to comply with the protocol MAIN SCREENING INCLUSION CRITERIA 1. Patient has provided written informed consent for the main GUIDE study PICF 2. Patient has a detectable plasma mGSTP1 deoxyribonucleic acid (DNA) as measured by central laboratory at prescreening prior to commencing first cycle of docetaxel chemotherapy 3. Patient has commenced 3 cycles of docetaxel 4. Patient has undetectable plasma mGSTP1 DNA as measured by central laboratory from blood taken prior to the third cycle of docetaxel 5. Patient is willing and able to comply with all study requirements, including treatment, timing and/or nature of required assessments. MAIN SCREENING EXCCLUSION CRITERIA 1. Known hypersensitivity to docetaxel or its excipients 2. Concurrent illness, including severe infection that may jeopardise the ability of the patient to undergo the procedures outlined in this protocol with reasonable safety 3. Serious medical or psychiatric conditions that might limit the ability of the patient to comply with the protocol 4. Progressive disease by RECIST 1.1 within the first 3 cycles of docetaxel

Locations (8)

Border Medical Oncology Research Unit / The Border Cancer Hospital

Albury, New South Wales, Australia

Chris O'Brien Lifehouse

Camperdown, New South Wales, Australia

St Vincent's Hospital

Darlinghurst, New South Wales, Australia

Dubbo Base Hospital

Dubbo, New South Wales, Australia

Concord Repatriation General Hospital

Sydney, New South Wales, Australia

Frankston Hospital-Peninsula Health

Frankston, Victoria, Australia

Goulburn Valley Health

Shepparton, Victoria, Australia

LaTrobe Regional Hospital

Traralgon, Victoria, Australia

Outcomes

Primary Outcomes

Radiographic progression free survival (rPFS)

Radiographic progression free survival (rPFS) is defined as the time from enrollment (i.e. prior to cycle 4), the date of first documented progression on imaging by site investigator (PCWG3 criteria for bone lesions and RECIST 1.1 for soft tissue lesions) or death due to any cause.