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68Ga-PSMA-11 PET for the Diagnosis of Metastatic Castration Resistant Prostate Cancer

A Phase 2 Study of 68Ga-PSMA-11 PET in Patients With Metastatic Castration Resistant Prostate Cancer

Status
Terminated
Phases
Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT04716725
Enrollment
15
Registered
2021-01-20
Start date
2021-09-28
Completion date
2025-04-30
Last updated
2026-05-15

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Castration-Resistant Prostate Carcinoma, Metastatic Prostate Carcinoma, Stage IVA Prostate Cancer AJCC v8, Stage IVB Prostate Cancer AJCC v8, Stage IV Prostate Cancer AJCC v8

Brief summary

This phase II trial studies the use of 68Ga-PSMA-11 positron emission tomography (PET) in diagnosing patients with prostate cancer that continues to grow despite the surgical removal of the testes or medical intervention to block androgen production (castration resistant), and has spread to other places in the body (metastatic). 68Ga- PSMA-11 is a new imaging agent that may help get more detailed pictures of the tumor. This trial aims to see whether using 68Ga-PSMA-11 PET scans may help doctors learn more about where disease is located in the body.

Detailed description

PRIMARY OBJECTIVE: I. To determine whether the percent change from baseline to 16 weeks (+/- 8 weeks) in maximum standard uptake value (SUVmax) averaged across up to 16 lesions per patient (SUVmax-ave) is associated with \>= 50% decline from baseline in serum prostate specific antigen (PSA50) response. SECONDARY OBJECTIVES: I. To determine whether the percent change from baseline in SUVmax-ave on PSMA PET is associated with time-to-event endpoints including PSA progression-free survival and overall survival. II. To determine whether the percent change from baseline in SUVmax on PSMA PET is associated with objective response by Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1 on a per-lesion basis among measurable soft tissue lesions present at baseline. EXPLORATORY (CORRELATIVE) OBJECTIVES: I. To descriptively characterize the histologic, transcriptional, and genomic features of PSMA low/negative lesions among patients who undergo paired optional metastatic tumor biopsy. II. To descriptively characterize the relationship between SUVmax-ave on baseline Ga-PSMA PET with optional baseline fludeoxyglucose F-18 (FDG)-PET. III. To determine whether heterogeneity of PSMA expression on baseline Ga-PSMA PET is associated with overall survival. IV. To descriptively characterize the patterns of PSMA expression at the time of disease progression among patients who undergo optional PSMA PET. V. To determine whether the percent change from baseline in PSMA PET is associated with PSA50 response among subgroups of patients defined by treatment modality received, including androgen receptor (AR) targeting treatment, PSMA-targeting radioligand therapy, cytotoxic chemotherapy, and immunotherapy. OUTLINE: Patients receive gallium Ga 68-PSMA-11 intravenously (IV) and undergo PET at baseline, 16 weeks after initiating therapy, and at time of disease progression. After progression or study completion, patients are followed up every 3 months for up to 24 months

Interventions

DRUG68Ga-PSMA-11

Given IV

PROCEDUREPositron Emission Tomography (PET)

Undergo PET

Sponsors

Thomas Hope
Lead SponsorOTHER
Conquer Cancer Foundation
CollaboratorOTHER
Gateway for Cancer Research
CollaboratorOTHER
Prostate Cancer Foundation
CollaboratorOTHER

Study design

Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
DIAGNOSTIC
Masking
NONE

Eligibility

Sex/Gender
MALE
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

1. Sub-cohort A1: Patients must have baseline evaluations performed within 12 weeks prior to the start of systemic therapy. 2. Sub-cohort A2: Patients must meet all the following requirements: * Have had a baseline pre-treatment 68Ga-PSMA-11 PET scan and PSA measurement performed within 12 weeks prior to the start of current systemic therapy. * Able to have an on-treatment 68Ga-PSMA-11 PET and a PSA measurement within 16 weeks (+/- 8 weeks) after the start of current systemic therapy. Note: The screening period for sub-cohort A2 is within 24 weeks after the patient started their current systemic therapy. 3. Patients must have progressive castration resistant prostate cancer, according to PCWG3 criteria. 4. Patients must have planned initiation of systemic treatment (sub-cohort A1), or ongoing systemic treatment (sub-cohort A2) for castration resistant prostate cancer within 12 weeks of baseline Ga-PSMA PET. 5. Patients must have at least one metastatic lesion with PSMA uptake at or above the blood pool on their baseline PSMA PET scan. 6. The patient must be able and willing to comply with study procedures and provide signed and dated informed consent. 7. Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1. 8. Patient must be Aged 18 years or older at the time of study entry. 9. Patients who undergo optional metastatic tumor biopsy following completion of baseline Ga-PSMA PET must additionally meet all of the following criteria: * Presence of one or more metastases by standard radiographic scans that is safely accessible to tumor biopsy in the judgment of treating clinician and/or Interventional Radiology. * No history of radiation therapy to the target metastatic lesion selected for tumor biopsy. * No contra-indication to biopsy including uncontrolled bleeding diathesis. * Platelets \> 75,000/ul and prothrombin time (PT) or institution normalized ratio (INR) and a partial thromboplastin time (PTT) \< 1.5 times the institutional upper limit of normal (ULN) within 14 days prior to biopsy.

Exclusion criteria

1. Patients who because of age, general medical or psychiatric condition, or physiologic status cannot give valid informed consent. 2. Patients with any condition that, in the opinion of the Principal Investigator, would impair the patient's ability to comply with study procedures. 3. Patients with any contra-indication to magnetic resonance imaging (MRI) (e.g. pacemaker placement, severe claustrophobia) Note: The

Design outcomes

Primary

MeasureTime frameDescription
Mean Maximum Standard Uptake Value (SUVmax)Baseline, and up to 16 weeks after initiation of therapyThe mean SUVmax and standard deviation across the primary tumor and the 5 largest lesions in each of three metastatic sites (nodal, visceral and osseous; for a maximum of 16 lesions per patient) will be descriptively reported.
Median SUVmaxBaseline, and up to 16 weeks after initiation of therapyThe median and range of SUVmax across the primary tumor and the 5 largest lesions in each of three metastatic sites (nodal, visceral and osseous; for a maximum of 16 lesions per patient) will be descriptively reported.
Percentage of Participants Who Progressed by Prostate-specific Antigen (PSA) Response GroupBaseline, and up to 16 weeks after initiation of therapyThe percent of participants who fall into the PSA50 responders vs. non-responders based on PSMA treatment response criteria (PPP) for progression status will be reported. PPP uses 3 different criteria to determine response: 1) Appearance of 2 or more new PSMA positive distant lesions, 2) Appearance of 1 new PSMA positive lesion plus consistent clinical and/or laboratory data and recommended confirmation by biopsy or correlative imaging within 3 months of PSMA PET, and 3) Increase in size or PSMA uptake of 1 or more existing lesions by 30% plus consistent clinical and/or laboratory data and/or confirmation by biopsy or correlative imaging within 3 months of PSMA PET.

Secondary

MeasureTime frameDescription
Progression Free Survival (PFS) by PET Response GroupUp to 48 monthsThe study cohort will be dichotomized by participants who fall into the responders vs. non-responders (progressed vs not progressed) based on PSMA PET response criteria (PPP) for progression status will be reported. PPP uses 3 different criteria to determine response: 1) Appearance of 2 or more new PSMA positive distant lesions, 2) Appearance of 1 new PSMA positive lesion plus consistent clinical and/or laboratory data and recommended confirmation by biopsy or correlative imaging within 3 months of PSMA PET, and 3) Increase in size or PSMA uptake of 1 or more existing lesions by 30% plus consistent clinical and/or laboratory data and/or confirmation by biopsy or correlative imaging within 3 months of PSMA PET. PSA progression-free will be defined by Prostate Cancer Clinical Trials Working Group 3 (PCWG3). The median PFS in months with 95% confidence interval will be reported.
Objective Response by PET Response GroupBaseline, and up to 16 weeks after initiation of therapyThe study cohort will be dichotomized by participants who fall into the responders vs. non-responders (progressed vs not progressed) based on PSMA PET response criteria (PPP) for progression status will be reported. PPP uses 3 different criteria to determine response: 1) Appearance of 2 or more new PSMA positive distant lesions, 2) Appearance of 1 new PSMA positive lesion plus consistent clinical and/or laboratory data and recommended confirmation by biopsy or correlative imaging within 3 months of PSMA PET, and 3) Increase in size or PSMA uptake of 1 or more existing lesions by 30% plus consistent clinical and/or laboratory data and/or confirmation by biopsy or correlative imaging within 3 months of PSMA PET. PSA progression-free will be defined by Prostate Cancer Clinical Trials Working Group 3 (PCWG3). The percentage of participants who obtained an objective response per Response Evaluation Criteria in Solid Tumors (RECIST) will be reported.
Overall Survival (OS) by PET Response GroupUp to 48 monthsThe study cohort will be dichotomized by participants who fall into the responders vs. non-responders (progressed vs not progressed) based on PSMA PET response criteria (PPP) for progression status will be reported. PPP uses 3 different criteria to determine response: 1) Appearance of 2 or more new PSMA positive distant lesions, 2) Appearance of 1 new PSMA positive lesion plus consistent clinical and/or laboratory data and recommended confirmation by biopsy or correlative imaging within 3 months of PSMA PET, and 3) Increase in size or PSMA uptake of 1 or more existing lesions by 30% plus consistent clinical and/or laboratory data and/or confirmation by biopsy or correlative imaging within 3 months of PSMA PET. PSA progression-free will be defined by Prostate Cancer Clinical Trials Working Group 3 (PCWG3). The median OS and 95% confidence interval will be reported.

Countries

United States

Contacts

PRINCIPAL_INVESTIGATORIvan A de Kouchovsky, MD

University of California, San Francisco

Participant flow

Participants by arm

ArmCount
Experimental (68Ga-PSMA-11 PET)
Patients receive gallium 68Ga-PSMA-11 IV and undergo PET at baseline, 16 weeks after initiating therapy, and at time of disease progression.
15
Total15

Baseline characteristics

CharacteristicExperimental (68Ga-PSMA-11 PET)
Age, Customized
40-49 years old
1 Participants
Age, Customized
50-59 years old
2 Participants
Age, Customized
60-69 years old
2 Participants
Age, Customized
70-79 years old
8 Participants
Age, Customized
80-89 years old
2 Participants
Ethnicity (NIH/OMB)
Hispanic or Latino
0 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
15 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
0 Participants
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants
Race (NIH/OMB)
Asian
3 Participants
Race (NIH/OMB)
Black or African American
0 Participants
Race (NIH/OMB)
More than one race
0 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants
Race (NIH/OMB)
Unknown or Not Reported
0 Participants
Race (NIH/OMB)
White
12 Participants
Region of Enrollment
United States
15 participants
Sex: Female, Male
Female
0 Participants
Sex: Female, Male
Male
15 Participants

Adverse events

Event typeEG000
affected / at risk
deaths
Total, all-cause mortality
3 / 15
other
Total, other adverse events
0 / 15
serious
Total, serious adverse events
0 / 15

Outcome results

Primary

Mean Maximum Standard Uptake Value (SUVmax)

The mean SUVmax and standard deviation across the primary tumor and the 5 largest lesions in each of three metastatic sites (nodal, visceral and osseous; for a maximum of 16 lesions per patient) will be descriptively reported.

Time frame: Baseline, and up to 16 weeks after initiation of therapy

Population: Data not collected

Primary

Median SUVmax

The median and range of SUVmax across the primary tumor and the 5 largest lesions in each of three metastatic sites (nodal, visceral and osseous; for a maximum of 16 lesions per patient) will be descriptively reported.

Time frame: Baseline, and up to 16 weeks after initiation of therapy

Population: Data not collected

Primary

Percentage of Participants Who Progressed by Prostate-specific Antigen (PSA) Response Group

The percent of participants who fall into the PSA50 responders vs. non-responders based on PSMA treatment response criteria (PPP) for progression status will be reported. PPP uses 3 different criteria to determine response: 1) Appearance of 2 or more new PSMA positive distant lesions, 2) Appearance of 1 new PSMA positive lesion plus consistent clinical and/or laboratory data and recommended confirmation by biopsy or correlative imaging within 3 months of PSMA PET, and 3) Increase in size or PSMA uptake of 1 or more existing lesions by 30% plus consistent clinical and/or laboratory data and/or confirmation by biopsy or correlative imaging within 3 months of PSMA PET.

Time frame: Baseline, and up to 16 weeks after initiation of therapy

Population: Participants were divided into subgroups based on whether or not the participant experienced a \>= 50% decline from baseline in serum PSA

ArmMeasureGroupValue (NUMBER)
Experimental (68Ga-PSMA-11 PET)Percentage of Participants Who Progressed by Prostate-specific Antigen (PSA) Response GroupPSA Responders who progressed11.1 percentage of participants by group
Experimental (68Ga-PSMA-11 PET)Percentage of Participants Who Progressed by Prostate-specific Antigen (PSA) Response GroupPSA Non-Responders who progressed83.3 percentage of participants by group
Secondary

Comparison Between Mean Percent Change in SUVmax With Objective Response Group

Amongst the subset of measurable soft tissue lesions by Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 criteria, on a per-lesion basis, the mean percent change from baseline in SUVmax on PSMA PET will be compared between responding lesions defined as a complete response or partial response by RECIST 1.1 criteria vs. those without response, using Mann-Whitney test.

Time frame: Baseline, and up to 16 weeks after initiation of therapy

Secondary

Comparison of Change in SUVmax-ave Group on Overall Survival (OS)

The study cohort will be dichotomized by the median with respect to percent change from baseline in SUVmax-ave on PSMA PET on overall survival defined as time from imaging until death or censored at study completion. OS will be compared between dichotomized subgroups using the log-rank test. Kaplan-Meier product limit method will be used to estimate median survival in each subgroup.

Time frame: Up to 24 months

Secondary

Comparison of Change in SUVmax-ave Group on Progression Free Survival (PFS)

The study cohort will be dichotomized by the median with respect to percent change from baseline in SUVmax-ave on PSMA PET. The time-to-event variables including PSA progression-free will be defined by Prostate Cancer Clinical Trials Working Group 3 (PCWG3).

Time frame: Up to 24 months

Source: ClinicalTrials.gov · Data processed: May 16, 2026