Phase 3
Completed N=122
68Ga-RM2 PET/MRI in Biochemically Recurrent Prostate Cancer
Source: ClinicalTrials.gov NCT02624518 ↗Enrolled (actual)
122
Serious AEs
0.0%
Results posted
Apr 2023
Primary outcomePrimary: Number of Tumor Lesions Detected by 68Ga-RM2 MRI vs 68Ga-RM2 PET/MRI — 92; 127 number of tumor lesions
◆ Published Evidence
Established
67citations · ~11 / year
Physiological <sup>68</sup>Ga-RM2 uptake in patients with biochemically recurrent prostate cancer: an atlas of semi-quantitative measurements.
Summary
Prostate cancer (PC) remains the most-common non-cutaneous cancer diagnosed in American males, accounting for an estimated 174,560 estimated new cases and 31,620 estimated deaths in 2019. Up to 40% of the patients with prostate cancer develop biochemical recurrence within 10 years after initial treatment. Usually an increase of the prostate-specific antigen (PSA) llevel precedes a clinically detectable recurrence by months to years, and this is currently used as a screening test before and subsequent to treatment. However, disease advancement can be local, regional or systemic, and each has significantly different approaches to disease management. Unfortunately, PSA level does not differentiate between these disease stages.
This phase 2-3 study explores the utility of radiolabel 68Ga-RM2, a 68-gallium (68Ga)-labeled gastrin-releasing peptide receptor (GRPr) antagonist, for positron emission tomography (PET) / magnetic resonance imaging (MRI) (collectively, PET/MRI) as a potential tool to help discriminate between disease stages in participants after treatment with surgery or radiation, who present persistently elevated PSA levels (ie, may have prostate cancer), but were negative for cancer with a diagnostic regular medical care computed tomography (CT) scan
68Ga-RM2 (BAY86-7548) is also identified as a synthetic bombesin receptor antagonist. PET/MRI is the collective result of 2 scan processes (PET and MRI ) conducted during the same scan procedure (ie, a combined scan). After a regular medical care computed tomography (CT) scan, participants will be scanned with 68Ga-RM2 PET/MRI scan procedure. PET/MRI is used to assess the location, size, and metabolic activity of a suspected tumor.
The 68Ga-RM2 radiolabel consisted of a ligand (the synthetic bombesin receptor antagonist) and the radioisotope 68Ga. The RM2 ligand targets gastrin-releasing peptide receptors (GRPr), commonly expressed by prostate cancer cells, and the radioisotope distinguishes those cells from the background. The criteria for scan "positivity" will be, when compared to background level of the liver (control), the 68Ga signal is stronger (positive - malignant) or weaker (negative - benign).
This study will assess how well 68Ga-RM2 works in detecting prostate cancer in patients with
68Ga-RM2 PET/MRI may be able to see smaller tumors than the standard of care contrast-enhanced CT or MRI scan.
Linked Publications (5)
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Physiological <sup>68</sup>Ga-RM2 uptake in patients with biochemically recurrent prostate cancer: an atlas of semi-quantitative measurements.
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PSMA- and GRPR-Targeted PET: Results from 50 Patients with Biochemically Recurrent Prostate Cancer.
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<sup>68</sup>Ga-RM2 PET-MRI versus MRI alone for evaluation of patients with biochemical recurrence of prostate cancer: a single-centre, single-arm, phase 2/3 imaging trial.
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Modified PROMISE criteria for standardized interpretation of gastrin-releasing peptide receptor (GRPR)-targeted PET.
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Reduced Acquisition Time per Bed Position for PET/MRI Using <sup>68</sup>Ga-RM2 or <sup>68</sup>Ga-PSMA-11 in Patients With Prostate Cancer: A Retrospective Analysis.
Outcome Measures
| Outcome | Result | p-value |
|---|---|---|
| PRIMARY Number of Tumor Lesions Detected by 68Ga-RM2 MRI vs 68Ga-RM2 PET/MRI |
92; 127 | — |
| PRIMARY Sensitivity of MRI Alone vs PET/MRI |
48.2; 91.8 | — |
| PRIMARY Specificity of MR Alone vs PET/MRI |
97.2; 88.9 | — |
Eligibility Criteria
Inclusion Criteria
- Biopsy proven prostate adenocarcinoma
- Rising PSA after definitive therapy with prostatectomy or radiation therapy (external beam or brachytherapy
- Post radical prostatectomy (RP) - American Urological Association (AUA) recommendation
- PSA greater than 0.2 ng/mL measured 6-13 weeks after RP
- Confirmatory persistent PSA greater than 0.2 ng/mL
- Post-radiation therapy - American Society for Therapeutic Radiology and Oncology (ASTRO)-Phoenix consensus definition
- Nadir plus (+) greater than or equal to 2 ng/mL rise in PSA
- No evidence of metastatic disease on conventional imaging, including a negative bone scan for skeletal metastasis and negative contrast-enhanced CT
- Able to provide written consent
- Karnofsky performance status of >= 50 (or Eastern Cooperative Oncology Group [ECOG]/World Health Organization [WHO] equivalent)
Exclusion Criteria
- Unable to provide informed consent
- Inability to lie still for the entire imaging time
- Inability to complete the needed investigational and standard-of-care imaging examinations due to other reasons (severe claustrophobia, radiation phobia, etc.)
- Any additional medical condition, serious intercurrent illness, or other extenuating circumstance that, in the opinion of the investigator, may significantly interfere with study compliance
- Metallic implants
Data sourced from ClinicalTrials.gov (NCT02624518) and the linked publication. Outcome figures and adverse-event rates are extracted automatically from the registry's posted results and are provided for clinician reference, not as a substitute for the primary publication. Informational only — not medical advice.