A Phase 2 interventional study of Minocycline 200mg/day and [18F]FETrp PET/CT in Low Grade Glioma and Glioblastoma, sponsored by Barbara Ann Karmanos Cancer Institute. Not yet recruiting at 1 site in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-07-30.
Sponsored by Barbara Ann Karmanos Cancer Institute · Phase 2, Interventional, and Diagnostic
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:
2,132 studies on the registry are indexed under Glioblastoma; 464 are open to participants now.
This study's planned enrollment of 61 is above the median of 36 across 1,753 interventional studies indexed under Glioblastoma.
Browse Glioblastoma studies →Barbara Ann Karmanos Cancer Institute is the lead sponsor of 161 studies on the registry; 19 are open to participants now.
Of its 8 completed or terminated interventional studies of FDA-regulated products, 6 (75%) have results posted.
Counted across the registry records on this site, refreshed daily.
FOR ARMS 1-3
Inclusion Criteria:
Exclusion Criteria:
ADDITIONAL CRITERIA FOR ARM 1:
Inclusion Criteria:
ADDITIONAL CRITERIA FOR ARM 2:
Inclusion Criteria:
ADDITIONAL CRITERIA FOR ARM 3
Inclusion Criteria:
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
A 0–100 scale of how well someone can carry out everyday activities. 100 is no complaints and no signs of illness; 70 is able to look after yourself but not to work or keep up normal activity; 50 is needing considerable help and frequent medical care.
Studies often ask for 60 or 70 and above. Your doctor gives the score.
A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.
Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Blood tests of how long blood takes to clot. The INR is the prothrombin time (PT) put on a common scale; about 1 is usual for someone not taking a blood thinner.
Criteria often make an exception for people on a blood thinner such as warfarin, whose INR is raised on purpose.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Karnofsky performance status (KPS)
A 0–100 scale of how well someone can carry out everyday activities. 100 is no complaints and no signs of illness; 70 is able to look after yourself but not to work or keep up normal activity; 50 is needing considerable help and frequent medical care.
Studies often ask for 60 or 70 and above. Your doctor gives the score.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Biopsy and archival tissue
A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.
Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Corticosteroids (steroids)
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
INR, PT and aPTT (clotting tests)
Blood tests of how long blood takes to clot. The INR is the prothrombin time (PT) put on a common scale; about 1 is usual for someone not taking a blood thinner.
Criteria often make an exception for people on a blood thinner such as warfarin, whose INR is raised on purpose.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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
Arm 2. \[18F\]FETrp PET to differentiate post-treatment glioma progression from radiation-induced MRI changes
Diagnostic Test: [18F]FETrp PET/CT
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
Drug page: Minocycline
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 used in all three arms
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.
Time frame: 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.
Time frame: 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.
Time frame: From Baseline (within 2 weeks prior to treatment initiation) to 1-month post-treatment (30 days ± 5 days, up to 44 days).
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
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 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 SUV volume (V1\_PETsuv) 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\_PETsuv 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.
Time frame: 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
Assessment of pre-radiotherapy metabolic tumor volume (PETk-T1, in cm³) as an independent prognostic predictor of progression-free survival (PFS). A multivariable Cox proportional hazards regression model will calculate the adjusted hazard ratio (HR) and 95% confidence interval for PFS per unit increase in PETk-T1 volume. The model will adjust for baseline clinical covariates. PFS is defined as time from the date of diagnosis to the first documented and verified disease progression (defined by the RANO 2.0 criteria9). Patients who are lost to follow-up or without disease progression at time of data cut off are censored at the time of last known disease progression follow-up.
Time frame: 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
The diagnostic specificity 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. Specificity is calculated as the proportion of true-negative cases (radiation injury) correctly identified by PETk out of all true-negative cases.
Time frame: 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
The proportion of participants with a positive \[18F\]FETrp PET K L/C ratio (≥ 1.60) who are confirmed to have true tumor progression via the composite ground truth reference standard (RANO 2.0 MRI follow-up or histopathology).
Time frame: 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
The proportion of participants with a negative \[18F\]FETrp PET K L/C ratio (\< 1.60) who are confirmed to have radiation-induced injury via the composite ground truth reference standard (RANO 2.0 MRI follow-up or histopathology).
Time frame: 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.
Overall Diagnostic Accuracy of [18F]FETrp PET K L/C Ratio for Differentiating Tumor Progression From Radiation Injury in Arm 2
The total proportion of correctly classified cases (true positives plus true negatives) using the \[18F\]FETrp PET K L/C ratio threshold of 1.60 divided by the total number of evaluable suspicious contrast-enhancing lesions.
Time frame: 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.
Partial Area Under the Receiver Operating Characteristic Curve (pAUC) for [18F]FETrp PET K L/C Ratios in Arm 2
The partial area under the receiver operating characteristic (ROC) curve generated by varying the continuous \[18F\]FETrp PET K L/C ratio values to assess overall classification performance across a clinically relevant range of specificities, utilizing the composite ground truth reference standard.
Time frame: 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 PET Kinetic Influx Rate (K) Lesion-to-Contralateral (L/C) Ratios Following One Month of Standard of Care Plus IDO Inhibitor Treatment in Arm 3
The change in the \[18F\]FETrp PET K-map lesion-to-contralateral (L/C) ratio from baseline to 1 month post-treatment. It is analyzed in the per-protocol population (at least 80% pill compliance and evaluable paired imaging).
Time frame: From Baseline (within 2 weeks prior to treatment initiation) to 1-month post-treatment (30 days ± 5 days, up to 44 days).
Start is estimated for Sep 2026; primary completion for Jun 2031, 57 months later.
Of 198 non-industry phase 2 interventional studies under Glioblastoma, half reached primary completion within 59 months of starting (the median), counting those still running; a quarter within 41 and three quarters within 89. This study's planned 57 months is close to that.
Counting every sponsor, half of 249 studies reached it within 56 months; a quarter within 40 and three quarters within 87.
How these figures are worked out, and which studies are left out of them.
This study is not yet recruiting, as verified in Jul 2026. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Minocycline
Barbara Ann Karmanos Cancer Institute →