Positron Emission Tomography/Computed Tomography (PET/CT) Imaging in Patients Diagnosed With a Glioma

NCT07735819 | Not Yet Recruiting Phase 2 DMC FDA Drug

• 1 other identifier: 2026-055
• Study Type: interventional
• Target: 61
• Locations: 1 country
• Sites: 1

Brief Summary

The goal of this clinical trial is to evaluate Positron emission tomography/computed tomography (PET/CT) imaging with the radiotracer 1-(2-\[18F\]fluoroethyl)-l-tryptophan (\[18F\]FETrp) in patients diagnosed with a glioma. This study has 3 aims:

• to assess if the \[18F\]FETrp PET/CT can outperform Magnetic Resonance Imaging (MRI) by providing a better treatment target volume in newly diagnosed Stage 4 glioma patients
• better differentiate tumor progression from radiation induced MRI changes in post treatment stage 4 gliomas
• by giving a drug that can inhibit a pathway to allow objective assessment of treatment effects in low grade gliomas

Conditions

Low Grade Glioma; Glioblastoma

Outcome Measures

Primary Outcomes (3)

• Difference Between Dice Similarity Coefficients (DSC) of Position Emission Tomography (PET) High K Tumor Volume and DSC of MRI-based Tumor Volume (d-PETk-MRI) in Arm 1

  A comparative evaluation of the predictive accuracy of pre-radiotherapy imaging modalities (V1) in forecasting the spatial location of future tumor progression (V2) defined by RANO (Response Assessment in Neuro-Oncology) 2.0 criteria. For each participant, two separate Dice Similarity Coefficients (DSC) will be calculated against the final progression volume (V2): one using the pre-radiotherapy PET High K influx map volume (V1\_PETk) and one using the structural MRI target volume (V1\_MRI). The primary endpoint (d-PETk-MRI) is the absolute difference calculated per patient as DSC\_PETk minus DSC\_MRI. The resulting continuous score ranges from -1 to +1. A positive score indicates that the novel kinetic PET parameter is a spatially superior predictor of subsequent localized tumor recurrence compared to standard clinical MRI planning fields.

  From the time of the pre-radiotherapy scans (Baseline) up to tumor progression or study completion, assessed at a maximum follow-up of 2 years.

• Sensitivity of [18F]FETrp PET Kinetic Influx Rate (PETk) with a predefined L/C ratio threshold of 1.60 in differentiating Tumor Progression from Radiation Injury in Arm 2

  The diagnostic sensitivity of PETk post-radiation (T2) (PETk-T2) with a predefined L/C ratio threshold of 1.60 to correctly identify true glioblastoma progression. The true disease status (ground truth) is defined by follow-up serial MRIs using RANO 2.0 criteria or histopathologic evidence from surgical re-resection. Sensitivity is calculated as the proportion of true-positive tumor progression cases correctly identified by PETk out of all true-positive cases.

  From the date of the [18F]FETrp PET/CT scan up to the date of confirmed ground truth designation via histopathology or serial MRI follow-up, assessed over a maximum period of 1 year per participant.

• Change in [18F]FETrp Kinetic Influx Rate (K) Values Following One Month of Standard of Care Plus Indoleamine 2,3-dioxygenase (IDO) Inhibitor Treatment (d-PETK) in Arm 3

  The quantitative change in \[18F\]FETrp PET K values evaluated within the MRI-defined tumor mass from baseline to post treatment. The primary analysis will be performed on the per-protocol population, defined as participants who completed both pre- and post-treatment PET scans and demonstrated at least 80% drug compliance via pill counts and paper diaries. Changes will be calculated as post-treatment minus baseline values, with a negative value indicating a reduction in tumoral tryptophan metabolic rates resulting from kynurenine pathway inhibition.

  From Baseline (within 2 weeks prior to treatment initiation) to 1-month post-treatment (30 days ± 5 days, up to 44 days).

Secondary Outcomes (8)

• Difference Between Dice Similarity Coefficients (DSC) of PET High Standardized Uptake Value (SUV) Tumor Volume and DSC of MRI-based Tumor Volume (d-PETsuv-MRI) in Arm 1

  From the time of the pre-radiotherapy scans (Baseline) up to tumor progression or study completion, assessed at a maximum follow-up of 2 years.

• Hazard Ratio for Progression-Free Survival Based on Pre-Radiotherapy (T1) [18F]FETrp PET High K Tumor Volume (PETk-T1) in Arm 1

  From date of initial diagnosis up to first documented RANO 2.0 disease progression, death, or study closure, assessed up to a maximum of 2 years.

• Specificity of [18F]FETrp PET Kinetic Influx Rate (PETk) with a predefined L/C ratio threshold of 1.60 in differentiating Tumor Progression from Radiation Injury in Arm 2

  From the date of the [18F]FETrp PET/CT scan up to the date of confirmed ground truth designation via histopathology or serial MRI follow-up, assessed over a maximum period of 1 year per participant.

• Positive Predictive Value (PPV) of [18F]FETrp PET K L/C Ratio for Glioblastoma Progression in Arm 2

  From the date of the [18F]FETrp PET/CT scan up to the date of confirmed ground truth designation via histopathology or serial MRI follow-up, assessed over a maximum period of 1 year per participant.

• Negative Predictive Value (NPV) of [18F]FETrp PET K L/C Ratio for Glioblastoma Progression in Arm 2

  From the date of the [18F]FETrp PET/CT scan up to the date of confirmed ground truth designation via histopathology or serial MRI follow-up, assessed over a maximum period of 1 year per participant.

Study Arms (3)

[18F]FETrp PET/CT in newly diagnosed grade 4 glioma prior to radiation

EXPERIMENTAL

Arm 1. \[18F\]FETrp PET prior to radiotherapy in newly diagnosed grade 4 glioblastoma to provide a better treatment target volume

Diagnostic Test: [18F]FETrp PET/CT

[18F]FETrp PET/CT in previously treated gliomas with post radiation progression

EXPERIMENTAL

Arm 2. \[18F\]FETrp PET to differentiate post-treatment glioma progression from radiation-induced MRI changes

Diagnostic Test: [18F]FETrp PET/CT

[18F]FETrp PET/CT pre and post Minocycline 200mg/day

EXPERIMENTAL

Arm 3. Minocycline orally 200mg/day administered between the first \[18F\]FETrp PET scan and the month follow up \[18F\]FETrp scan to determine if pharmacologic inhibition of the kynurenine pathway will reduce tumoral tryptophan metabolic rates in low-grade gliomas

Drug: Minocycline 200mg/day; Diagnostic Test: [18F]FETrp PET/CT

Interventions

Minocycline 200mg/day DRUG

Minocycline 200mg orally daily to start within 14 days of the first \[18F\]FETrp PET/CT and taken until the second \[18F\]FETrp PET/CT obtained 25-44 days after the start of the Minocycline in Arm 3

[18F]FETrp PET/CT pre and post Minocycline 200mg/day

[18F]FETrp PET/CT DIAGNOSTIC_TEST

\[18F\]FETrp PET/CT used in all three arms

[18F]FETrp PET/CT in newly diagnosed grade 4 glioma prior to radiation; [18F]FETrp PET/CT in previously treated gliomas with post radiation progression; [18F]FETrp PET/CT pre and post Minocycline 200mg/day

Eligibility Criteria

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

You may qualify if:

• Age =18 years.
• Patient is able to lie in the PET/CT scanner for at least 60 minutes while undergoing scanning.
• Patient is willing and able to review, understand, and provide written consent for the study procedures and indicates that they are aware of the investigational nature of this study.

You may not qualify if:

• Patients who are pregnant or lactating are excluded. Premenopausal women (defined per institutional guidelines) must have a negative pregnancy test (urine or serum) within 7 days of the PET scan.
• Severe increased intracranial pressure, status epilepticus, or other severe or progressing clinical symptoms requiring urgent intervention in the opinion of the treating
• Karnofsky performance score \<60, as determined by one of the clinician co- investigators.
• ADDITIONAL CRITERIA FOR ARM 1:
• Histopathology/cytopathological diagnosis of a glioblastoma without a history of radiation.
• The tumor is deemed amenable for radiation treatment (pre-radiation planning MRI can be done before or after the PET scan).
• ADDITIONAL CRITERIA FOR ARM 2:
• Previous histopathology/cytopathological diagnosis of glioblastoma.
• History of glioma radiation.
• Presence of a new or progressing enhancing brain lesion on follow-up clinical MRI suspicious for post-radiation glioma progression or late radiation-induced MRI changes (i.e., radiation injury), at least 7 mm in bidirectional diameter.
• The most recent MRI, used for comparison with the PET/CT, is performed within 4 weeks of the planned PET scan.
• ADDITIONAL CRITERIA FOR ARM 3
• MRI diagnosis of a brain tumor, previously verified to be a low-grade (WHO grade 2, IDH (isocitrate dehydrogenase) mutant glioma, based on histopathology from biopsy or resection.
• The detected mass on the most recent clinical MRI is at least 7 mm in bidirectional diameter (i.e., twice the PET scanner resolution).
• The tumor does not require urgent (within 1 month) resection, steroid treatment, or radiation.

Sponsors & Collaborators

• Barbara Ann Karmanos Cancer Institute: lead
• Wayne State University: collaborator

Study Sites (1)

Karmanos Cancer Institute

Detroit, Michigan, 48201, United States

Location

MeSH Terms

Conditions

Glioblastoma

Interventions

Minocycline

Condition Hierarchy (Ancestors)

Astrocytoma; Glioma; Neoplasms, Neuroepithelial; Neuroectodermal Tumors; Neoplasms, Germ Cell and Embryonal; Neoplasms by Histologic Type; Neoplasms; Neoplasms, Glandular and Epithelial; Neoplasms, Nerve Tissue

Intervention Hierarchy (Ancestors)

Tetracyclines; Naphthacenes; Polycyclic Aromatic Hydrocarbons; Hydrocarbons, Aromatic; Hydrocarbons, Cyclic; Hydrocarbons; Organic Chemicals; Polycyclic Compounds

Study Officials

• Csaba Juhasz, M.D.,Ph.D.

  Wayne State University

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Csaba Juhasz, M.D.,Ph.D.

CONTACT

313-966-5136; csaba.juhasz@wayne.edu

Study Design

• Study Type: interventional
• Phase: phase 2
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: DIAGNOSTIC
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator

Study Record Dates

• First Submitted: July 24, 2026
• First Posted: July 30, 2026
• Study Start (Estimated): September 1, 2026
• Primary Completion (Estimated): June 30, 2031
• Study Completion (Estimated): June 30, 2031
• Last Updated: July 30, 2026

Record last verified: 2026-07

Locations

US (1)