Efficacy of Ra-223 in PSMA PET Optimally Selected Patients

NCT05924672 | Active Not Recruiting Phase 2 DMC FDA Drug

• 2 other identifiers: 23923NCI-2023-04656
• Study Type: interventional
• Target: 2
• Locations: 1 country
• Sites: 1

Brief Summary

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.

Conditions

Castration-Resistant Prostate Carcinoma; Metastatic Malignant Neoplasm in the Bone; Stage IVB Prostate Cancer AJCC v8

Outcome Measures

Primary Outcomes (1)

• PSA50 response rate

  The proportion of patients who achieve a greater than 50% decline from baseline prostate specific antigen (PSA) (PSA50) drawn prior to C1D1, at any point in the treatment course, will be descriptively reported along with 95% binomial confidence interval. It will be compared with the historical control by binomial test. A confirmation repeat PSA will be drawn after the initial PSA50 response to confirm the result. A PSA50 will only be counted if two PSA showing a 50% decline are measured.

  Up to 6 months

Secondary Outcomes (5)

• PSA30 response rate

  Up to 6 months

• Overall Survival

  Up to 2 years

• Time to first skeletal symptomatic event

  Up to 30 days after the last dose of Ra-223 treatment

• Proportion of participants reporting treatment-related adverse events

  Up to 30 days after the last dose of Ra-223 treatment

• Compare the lesion based PSMA PET response based on paired NaF PET / MDP uptake

  Up to 30 days after the last dose of Ra-223 treatment

Study Arms (1)

Treatment (NaF PET/CT/MDP, Ra-223, PSMA PET)

EXPERIMENTAL

Patients undergo NaF PET/CT or MDP scan within 45 days prior to cycle 1 day 1. Patients then receive standard of care Ra-223 IV on day 1 of each cycle. Treatment repeats every 28 days for 6 cycles in the absence of disease progression or unacceptable toxicity. Patients then undergo PSMA PET/CT over 45-60 minutes between 30-60 days after the last dose of Ra-223. Patients also undergo collection of blood samples during screening, on day 1 of every Ra-223 cycle, and at 30 days after the last dose of Ra-223. Patients may also undergo NaF PET/CT or MDP scans during Ra-223 treatment as clinically indicated, and/or CT scans during screening and Ra-223 treatment as clinically indicated.

Drug: Radium-223; Procedure: PSMA Positron Emission Tomography (PET) Scan; Drug: Technetium Tc 99M Medronate

Interventions

Radium-223 DRUG

Given IV

Also known as: Ra-223, BAY 88-8223, BAY88-8223, Radium 223 Dichloride, Xofigo

Treatment (NaF PET/CT/MDP, Ra-223, PSMA PET)

PSMA Positron Emission Tomography (PET) Scan PROCEDURE

Undergo PSMA PET/CT

Also known as: Prostate-specific Membrane Antigen (PSMA) PET, PSMA PET

Treatment (NaF PET/CT/MDP, Ra-223, PSMA PET)

Technetium Tc 99M Medronate DRUG

Undergo MDP

Also known as: (99m)Tc-Medronate, 121524-79-6, 99mTc-MDP, TechneScan MDP, Technetium Tc 99m Methylene Diphosphonate

Treatment (NaF PET/CT/MDP, Ra-223, PSMA PET)

Eligibility Criteria

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

You may qualify if:

• Male participants \>= 18 years of age on the day of signing informed consent
• Castrate level of serum testosterone at study entry (\< 50 ng/dL), checked within three months of enrollment
• Patient is a candidate for standard of care Ra-223 therapy
• Bone only disease on PSMA PET using a Food and Drug Administration (FDA) approved PSMA targeted PET radiopharmaceutical
• 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
• Positivity on PSMA PET is defined as uptake greater than the liver that is not attributable to physiologic activity
• Histologically confirmed prostate adenocarcinoma that is progressive by Prostate Cancer Working Group 3 (PCWG3) criteria at the time of study entry
• Prior progression on at least one second generation androgen signaling inhibitor including abiraterone, apalutamide, darolutamide, and/or enzalutamide
• Platelets \> 100,000/microliter (mcL)
• Hemoglobin (Hgb) \> 9.0 g/dL
• White blood cells (WBC) \> 2.5
• Albumin \> 3.0 g/dL
• Adverse events related to prior anti-cancer treatment must have recovered to =\< Grade 2
• 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

You may not qualify if:

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

Sponsors & Collaborators

• University of California, San Francisco: lead
• Bayer Healthcare Pharmaceuticals, Inc./Bayer Schering Pharma: collaborator

Study Sites (1)

University of California, San Francisco

San Francisco, California, 94143, United States

Location

MeSH Terms

Conditions

Prostatic Neoplasms

Interventions

Radium-223; radium Ra 223 dichloride; 2-phenyl-6-(2'-(4'-(ethoxycarbonyl)thiazolyl))thiazolo(3,2-b)(1,2,4)triazole; Glutamate Carboxypeptidase II; Technetium Tc 99m Medronate

Condition Hierarchy (Ancestors)

Genital Neoplasms, Male; Urogenital Neoplasms; Neoplasms by Site; Neoplasms; Genital Diseases, Male; Genital Diseases; Urogenital Diseases; Prostatic Diseases; Male Urogenital Diseases

Intervention Hierarchy (Ancestors)

Carboxypeptidases; Exopeptidases; Peptide Hydrolases; Hydrolases; Enzymes; Enzymes and Coenzymes; Metalloexopeptidases; Metalloproteases; Organotechnetium Compounds; Organometallic Compounds; Organic Chemicals; Diphosphonates; Organophosphonates; Organophosphorus Compounds

Study Officials

• Thomas A Hope, MD

  University of California, San Francisco

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: phase 2
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: June 20, 2023
• First Posted: June 29, 2023
• Study Start: August 30, 2024
• Primary Completion: January 7, 2026
• Study Completion (Estimated): March 31, 2027
• Last Updated: January 14, 2026

Record last verified: 2026-01

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)