Duration of Androgen Receptor Pathway Inhibitor and ADT With Metastasis Directed Therapy in Oligometastatic Cancer of the Prostate (DIRECT)

University Health Network, Toronto

Status and phase: Enrolling; Phase 2

Conditions: Metastatic Prostate Cancer

Treatments: Drug: Enzalutamide; Other: Standard of Care SBRT and ADT

Study type: Interventional

Funder types: Other; Industry

Identifiers

NCT05404139

22-5274

Details and patient eligibility

About

This is a multi-centre, investigator-initiated, two-arm, randomized trial to investigate the addition on androgen receptor pathway inhibitor to standard of care radiation and hormone therapy improve quality of life.

Participants will either receive standard of care radiation and hormone (ADT) therapy (Arm 1) or standard of care radiation and hormone (ADT) therapy plus oral abiraterone for 8-9 months (Arm 3). Participants will be routinely follow-up in clinic or remotely for up to 5 years.

Enrollment: 132 estimated patients

Sex: Male

Ages: 18 to 100 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

1. Age > 18 years

2. Able to provide informed consent

3. Histologic diagnosis of prostate adenocarcinoma

4. ECOG performance status 0-2

5. Stage IV castrate sensitive metachronous metastatic prostate cancer. diagnosed within 6 months of study enrollment with 1-10 metastases

   1. Maximum one metastatic deposit on conventional imaging (CT or bone scan or MR)
   2. Additional metastases can be detectable by PSMA PET only

6. All sites of disease are amenable to and can be safely treated with radiotherapy

7. Patients decline continuous use of ADT

Exclusion criteria

1. Significant comorbidities rendering patient not suitable for ADT, enzalutamide and SBRT
2. History of malignancy within the past 5 years, excluding non-melanoma skin cancer and in-situ cancer, managed non-curatively
3. Prior use of salvage systemic therapy
4. Evidence of spinal cord compression

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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132 participants in 2 patient groups

Arm 1 - Standard of Care

Other group

Description:

Participants in this group will receive standard of care radiation treatment and ADT. Participants will start ADT first. Androgen deprivation therapy will be delivered via injection every 4 months as per standard of care (for 8 months total). At the same time, or within 3 months of starting ADT, participants will begin radiation treatment. The radiation treatment course will consist of 2-5 sessions of radiation daily or every other day (the number of sessions will be determined by the physician depending on the location of cancer, number of cancer spots, etc.).

Treatment:

Other: Standard of Care SBRT and ADT

Arm 3 - Study Treatment

Experimental group

Description:

Participants in this group will receive standard of care radiation treatment and ADT, plus abiraterone. Participants will start ADT first. Androgen deprivation therapy will be delivered via injection every 4 months as per standard of care (for 8 months total). At the same time, or within 3 months of starting ADT, participants will begin radiation treatment. The radiation treatment course will consist of 2-5 sessions of radiation daily or every other day (the number of sessions will be determined by the physician depending on the location of cancer, number of cancer spots, etc.). In addition, participants will take abiraterone orally (by mouth) daily for 8-9 months. Participants will start the first pill within a month of enrollment. This pill can be taken around the same time of day with or without food.

Treatment:

Other: Standard of Care SBRT and ADT

Drug: Enzalutamide