Clinical Trial · NCT05924672

Efficacy of Ra-223 in PSMA PET Optimally Selected Patients

Overview

This phase II trial studies how well prostate-specific membrane antigen (PSMA) positron emission tomography (PET) scans (in combination with bone scans) work in selecting patients for Ra-223 radiation therapy that have castration-resistant prostate cancer that has spread from where it first started (primary site) to the bones (bone metastasis). Ra-223 is a type of therapy that emits radiation. Radiation gives off energy which can kill tumor cells and other cells that may support the tumor cells. Ra-223 is given by infusion into the veins, where it is absorbed by the bones. PSMA PET is a type of scan used to detect prostate cancer tumors. PSMA is a radioactive tracer that binds to a specific protein that is found on prostate tumor cells. The PSMA tracer shows the areas on the PET scan where tumor cells are active. A PET scan uses a special camera to detect the energy given off from radioactive tracers (such as PSMA) to make detailed pictures of areas where the tracer accumulates in the body. The PET scan is often combined with a magnetic resonance imaging (MRI) or computed tomography (CT) scan, which helps to map the locations where PSMA has accumulated. PSMA PET scans may be able to select patients that will benefit the most from Ra-223 treatment.

Sponsor

University of California, San Francisco

Phase

Phase 2

Contacts

Thomas A Hope, MD (PRINCIPAL_INVESTIGATOR)

ClinicalTrials.gov

NCT05924672

Drug / Compound

Medronate

Isotope(s):
Target(s):
  • Bone Metabolism
Ligand Class: Small Molecules

dichloride

Isotope(s):
Target(s):
  • Bone Metabolism
Ligand Class: Small Molecules

Eligibility

Inclusion

  • Adverse events related to prior anti-cancer treatment must have recovered to =\< Grade 2
  • Positivity on PSMA PET is defined as uptake greater than the liver that is not attributable to physiologic activity
  • Patient is a candidate for standard of care Ra-223 therapy
  • Platelets \> 100,000/microliter (mcL)
  • White blood cells (WBC) \> 2.5
  • Histologically confirmed prostate adenocarcinoma that is progressive by Prostate Cancer Working Group 3 (PCWG3) criteria at the time of study entry
  • Eastern Cooperative Oncology Group (ECOG) performance status of 0 to 2
  • For patients who have partners of childbearing potential: Partner and/or patient must use a method of birth control with adequate barrier protection, deemed acceptable by the principal investigator during the study and for 3 months after last study drug administration
  • Hemoglobin (Hgb) \> 9.0 g/dL
  • Individuals with a prior or concurrent malignancy whose natural history or treatment does not have the potential to interfere with the safety or efficacy assessment of the investigational regimen are eligible for this trial
  • Note: Nodal disease on PSMA PET that is less than 1 cm in short axis and without evidence of change in size over the past six months on conventional imaging is allowed
  • Castrate level of serum testosterone at study entry (\< 50 ng/dL), checked within three months of enrollment
  • Bone only disease on PSMA PET using a Food and Drug Administration (FDA) approved PSMA targeted PET radiopharmaceutical
  • Albumin \> 3.0 g/dL
  • Prior progression on at least one second generation androgen signaling inhibitor including abiraterone, apalutamide, darolutamide, and/or enzalutamide

Exclusion

  • Prior exposure to taxane-based chemotherapy. \* Note: Exposure is defined as two or more cycles of taxane-based agents
  • Any condition that, in the opinion of the Principal Investigator, would impair the patient's ability to comply with study procedures
  • Greater than 75% bone involvement, based on PSMA PET
  • Prior treatment with radioligand therapy
  • Presence of visceral metastases, untreated central nervous system metastases, or untreated epidural or spinal cord involvement
  • Any systemic anti-cancer therapy (e.g., chemotherapy, immunotherapy or biological therapy, including monoclonal antibodies) within 21 days prior to the first day of treatment
  • Blood transfusion within past 45 days
  • Prior treatment with Lutetium-177 (177Lu)-PSMA-617, Radium-223, Strontium-89, Samarium-153, Rhenium-186, Rhenium-188