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68Ga-PSMA-11 PET/CT for the Diagnosis of Bone Metastases in Patients With Prostate Cancer and Biochemical Progression During Androgen Deprivation Therapy

Phase 2
Terminated
Conditions
Stage IVA Prostate Cancer AJCC v8
Biochemically Recurrent Prostate Carcinoma
Metastatic Prostate Carcinoma
Metastatic Malignant Neoplasm in the Bone
Stage IV Prostate Cancer American Joint Committee on Cancer (AJCC) v8
Stage IVB Prostate Cancer AJCC v8
Interventions
Procedure: Computed Tomography
Other: Gallium Ga 68 Gozetotide
Procedure: Positron Emission Tomography
Registration Number
NCT04928820
Lead Sponsor
Jonsson Comprehensive Cancer Center
Brief Summary

This phase II trial studies how well 68Ga-PSMA-11 positron emission tomography (PET)/computed tomography (CT) works in detecting the spread of cancer to the bones (bone metastasis) in patients with prostate cancer and increased PSA after treatment (biochemical recurrence) during androgen deprivation therapy. Diagnostic procedures, such as 68Ga-PSMA-11 PET/CT, may help find and diagnose prostate cancer and find out how far the disease has spread.

Detailed Description

PRIMARY OBJECTIVE:

I. To compare the per-patient detection rate of 68Ga-PSMA-11 PET/CT versus bone scan (BS)/CT for M1b in patients treated with androgen deprivation therapy (ADT) who are referred for the imaging evaluation of disease progression.

SECONDARY OBJECTIVES:

I. To compare the number of lesions rated as positive for bone metastases between the two imaging tests.

II. To compare the detection rate of 68Ga-PSMA PET/CT versus BS/CT for all M1 disease (M1a or M1b or M1c).

III. To compare the positive predictive value (PPV) per-patient in patients with lesion validation (follow-up imaging or biopsy).

OUTLINE:

Patients receive gallium Ga 68 gozetotide intravenously (IV). After 50-100 minutes, patients undergo whole body PET/CT.

Recruitment & Eligibility

Status
TERMINATED
Sex
Male
Target Recruitment
22
Inclusion Criteria
  • Patient with biochemical progression during ADT or combination therapies including ADT who are referred for imaging evaluation (prostate specific antigen [PSA] level >= 1 ng/ml that has increased on at least 2 successive occasions at least 1 weak apart)

  • Patients with bone scan scheduled or performed

    • Within 30 days of the PSMA PET, without any new prostate cancer (PCa) therapy in between
    • Bone scans performed at University of California, Los Angeles (UCLA) and external institutions are eligible if Digital Imaging and Communications in Medicine (DICOM) images can be obtained, imported, and anonymized
  • Patients enrolled in other clinical trials are eligible if they satisfy all other criteria of eligibility

  • Patients or their legal representatives must have the ability to read, understand and provide written informed consent

Exclusion Criteria
  • Initiation of a new therapy between the PSMA PET/CT and the bone scans
  • Inability to provide written informed consent
  • Known inability to remain still and lie flat for duration of each imaging procedure (about 30 minutes)

Study & Design

Study Type
INTERVENTIONAL
Study Design
SINGLE_GROUP
Arm && Interventions
GroupInterventionDescription
Diagnostic (68Ga-PSMA-11 PET/CT)Positron Emission TomographyPatients receive gallium Ga 68 gozetotide IV. After 50-100 minutes, patients undergo whole body PET/CT.
Diagnostic (68Ga-PSMA-11 PET/CT)Computed TomographyPatients receive gallium Ga 68 gozetotide IV. After 50-100 minutes, patients undergo whole body PET/CT.
Diagnostic (68Ga-PSMA-11 PET/CT)Gallium Ga 68 GozetotidePatients receive gallium Ga 68 gozetotide IV. After 50-100 minutes, patients undergo whole body PET/CT.
Primary Outcome Measures
NameTimeMethod
Per-patient detection rate of gallium Ga 68 gozetotide (68Ga-PSMA-11) positron emission tomography (PET)/computed tomography (CT)Up to 4 years

68Ga-PSMA-11 PET will be compared to bone scan/CT for M1b disease in prostate cancer patients progressing during androgen deprivation therapy. Patients who have at least one positive bone lesion will be rated positive. Patients will be treated as binary categorization. The analysis of the primary objective will utilize the McNemar's test to compare the detection rate between the imaging techniques.

Secondary Outcome Measures
NameTimeMethod
Per-patient positive predictive value (PPV)Up to 4 years

Per-patient PPV estimates (with 95% confidence interval), defined as the number true positive findings the total number of positive cases (TP + FP). The lesions will be considered true positive on the basis of biopsy information, follow-up imaging, or changes in prostate specific antigen (PSA) levels. This information will only be available in a small subset of patients.

Number of lesions found by PSMA PET and bone scan + CTUp to 4 years

Will be compared using a paired samples t-test.

Rate of M1 detectionUp to 4 years

Will be compared between the two modalities, defined as the number of patients with positive finding(s) for M1 disease (M1a or M1b or M1c), will utilize the McNemar's test for paired proportions.

Incidence of adverse eventsUp to 4 years

Assessed using Common Terminology Criteria for Adverse Events version 4.03.

PSA progression-free survival (PFS)Up to 4 years

Univariate Cox proportional hazards models for PFS will be constructed with models containing various patient characteristics as well as PSMA PET parameters and bone scan parameters. Hazard ratios with 95% confidence intervals as well as p-values will be tabulated. Next, will explore multivariate models (using LASSO variable selection) including terms for important baseline characteristics as well as PSMA parameters or bone scan parameters and will extract the survival concordance indices from each of these models and compare them.

Overall survival (OS)Up to 4 years

Univariate Cox proportional hazards models for OS will be constructed with models containing various patient characteristics as well as PSMA PET parameters and bone scan parameters. Hazard ratios with 95% confidence intervals as well as p-values will be tabulated. Next, will explore multivariate models (using LASSO variable selection) including terms for important baseline characteristics as well as PSMA parameters or bone scan parameters and will extract the survival concordance indices from each of these models and compare them.

Trial Locations

Locations (1)

University of California at Los Angeles / Jonsson Comprehensive Cancer Center

🇺🇸

Los Angeles, California, United States

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