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A Pilot Study to Evaluate PBR PET in Brain Tumor Patients Treated With Chemoradiation or Immunotherapy

A Pilot Study to Evaluate PBR PET in Brain Tumor Patients Treated With Chemoradiation or Immunotherapy

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT02431572
Enrollment
11
Registered
2015-05-01
Start date
2015-05-31
Completion date
2019-02-28
Last updated
2020-04-28

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

Conditions

Glioblastoma, Intracranial Tumors, Melanoma

Keywords

Intracranial Tumors, Glioblastoma, Melanoma

Brief summary

This research study is studying the changes in primary and metastatic brain tumor inflammation using positron emission tomography (PET) imaging using a radioactive substance called \[11C\] PBR28a, which is also known as peripheral benzodiazepine receptors (PBR), or PBR-PET.

Detailed description

This research study is a Pilot Study, which is the first time investigators are examining this study intervention. The purpose of a pilot study is to obtain the preliminary data needed to justify performing a larger clinical trial on the effectiveness of an investigational intervention. Standard treatment for the subjects' disease includes chemoradiation and immunotherapy. In PET scans, a radioactive substance is injected into the body. The scanning machine finds the radioactive substance, which tends to go to cancer cells and areas of inflammation. For the PET scans in this study, the investigators are using a radioactive substance called \[11C\]PBR28. The investigators would like to see if this tracer can be used to detect changes in inflammation during tumor treatment. PBR-PET scans will be performed at screening before therapy and then several weeks/months after the start of therapy, depending on the type of therapy used. No diagnostic decisions or clinical treatment decisions will be made based on any results obtained from these PET scans, and there will be no change in care. The information from these studies may help the investigators design methods that could be used in larger studies to more completely understand the role of inflammation in the treatment of cancer.

Interventions

OTHERPBR PET
BIOLOGICALCancer Immunotherapy

Subjects who are to be treated with immunotherapy for glioblastoma or melanoma brain metastases will be eligible for 2 of the 3 arms.

RADIATIONRadiation and chemotherapy

Subjects with glioblastoma will receive or will have received treatment with chemotherapy and radiation per the standard of care.

Sponsors

Massachusetts General Hospital
Lead SponsorOTHER

Study design

Allocation
NON_RANDOMIZED
Intervention model
PARALLEL
Primary purpose
DIAGNOSTIC
Masking
NONE

Eligibility

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

Inclusion criteria

* Participants must have evidence of metastatic melanoma to the brain for Cohort A or histologically confirmed GBM for Cohorts Band C. * Those with newly diagnosed GBM but suspected to have pseudoprogression after completion of chemoradiation can enroll in Cohort C. * Participants must have measurable brain disease, defined as at least one lesion that is 10 mm in diameter. * Age \> 18 years. * ECOG performance status ≤2 (Karnofsky ≥60%, see Appendix A) * Life expectancy of greater than 3 months. * Participants must have normal organ and marrow function as defined below: * leukocytes ≥3,000/mcL * absolute neutrophil count ≥1,500/mcL * platelets ≥100,000/mcL * total bilirubin within normal institutional limits * AST(SGOT)/ALT(SGPT) ≤2.5 × institutional upper limit of normal * creatinine within normal institutional limits \--- OR * creatinine clearance ≥60 mL/min/1.73 m2 for participants with creatinine levels above institutional normal. * For Cohort A, only patients with metastatic melanoma to the brain for whom their treating physician has planned to give immunotherapy as monotherapy are eligible for this study. This can be in the setting of a clinical trial or not. * For Cohort B, only patients with GBM for whom their treating physician has planned to give immunotherapy are eligible for this study. This can be in the setting of a clinical trial or not. * For Cohort C, patients with newly diagnosed GBM who have completed standard temozolomide + radiation and have suspected pseudoprogression within the first 3 months of completing chemoradiation can enroll. * Patient must be able to undergo MRI and PET scans. * Patient must be maintained on a stable corticosteroid regimen for 5 days prior each MR-PET scan. * High or mixed affinity binders (Ala/Ala or Ala/Thr) based on genotyping result from PBR affinity test. This blood test will be performed as part of the screening process after consent has been obtained. * The effects of PBR on the developing human fetus are unknown. For this reason and because radiopharmaceuticals agents are known to be teratogenic, women of child-bearing potential and men must agree to use adequate contraception (hormonal or barrier method of birth control; abstinence) prior to study entry and for the duration of study participation. Should a woman become pregnant or suspect she is pregnant while she or her partner is participating in this study, she should inform her treating physician immediately. Radiopharmaceutical agents are known to be teratogenic. * Ability to understand and the willingness to sign a written informed consent document.

Exclusion criteria

* History of allergic reactions attributed to compounds of similar chemical or biologic composition to PBR. * Uncontrolled intercurrent illness including, but not limited to, ongoing or active infection, symptomatic congestive heart failure, unstable angina pectoris, cardiac arrhythmia, or psychiatric illness/social situations that would limit compliance with study requirements. * Pregnant women are excluded from this study because PBR is a radiopharmaceutical agent with the potential for teratogenic or abortifacient effects. Because there is an unknown but potential risk for adverse events in nursing infants secondary to exposure of the mother to PBR, breastfeeding should be discontinued. These potential risks may also apply to other agents used in this study. * HIV-positive participants are excluded because their immune system is compromised and may affect the interpretation of the imaging data. * Patients who are not suitable to undergo MRI or PET or use gadolinium contrast due to: * Claustrophobia * Presence of metallic objects or implanted medical devices in body (i.e. cardiac pacemaker, aneurysm clips, surgical clips, prostheses, artificial hearts, valves with steel parts, metal fragments, shrapnel, tattoos near the eye, or steel implants) The craniotomy patients will all have titanium but this is MRI compatible * Sickle cell disease * Renal failure * Reduced renal function, as determined by creatinine clearance \< 30 mL/min based on a serum creatinine level obtained within 28 days prior to registration

Design outcomes

Primary

MeasureTime frameDescription
Change in PBR Uptake (Changes in PBR Uptake by PET)At baseline and 3 to 4 months post baselineThe change in PBR uptake in arms cohorts A and B from baseline to the start of cycle 4 for metastatic melanoma patients or cycle 3 for glioblastoma patients. The 18-kDa translocator protein (TSPO) is a protein that is expressed in mitochondria and is particularly prominently expressed by activated microglia, infiltrating macrophages, and reactive astrocytes. Thus, it is a marker of neuro-inflammation. PBR28 is a second generation PET tracer that binds to TPSO. PBR28 uptake was quantified using the standardized uptake value (SUV), which is the ratio of activity per unit volume of the region of interest (ROI) compared to cerebellum. Higher values indicate increased uptake in the ROI.
Median PBR UptakeAt the time of suspected pseudo-progression (up to 4 weeks after consent)The median PBR28 uptake as measured by positron emission tomography (PET) following chemo-radiation. The 18-kDa translocator protein (TSPO) is a protein that is expressed in mitochondria and is particularly prominently expressed by activated microglia, infiltrating macrophages, and reactive astrocytes. Thus, it is a marker of neuro-inflammation. PBR28 is a second generation PET tracer that binds to TPSO. PBR28 uptake was quantified using the standardized uptake value (SUV), which is the ratio of activity per unit volume of the region of interest (ROI) compared to cerebellum. Higher values indicate increased uptake in the ROI.

Countries

United States

Participant flow

Participants by arm

ArmCount
Metastatic Melanoma to the Brain (Cohort A)
* Assess Inflammation (PBR PET) * Immunotherapy * Assess Inflammation (PBR PET) PBR PET Cancer Immunotherapy: Subjects who are to be treated with immunotherapy for glioblastoma or melanoma brain metastases will be eligible for 2 of the 3 arms.
1
Primary Brain Tumor (Cohort B)
* Assess Inflammation (PBR PET) * Immunotherapy * Assess Inflammation (PBR PET) PBR PET Cancer Immunotherapy: Subjects who are to be treated with immunotherapy for glioblastoma or melanoma brain metastases will be eligible for 2 of the 3 arms.
1
Primary Brain Tumor (Cohort C)
* Chemoradiation * Assess inflammation (PBR PET) * Follow Patients PBR PET Radiation and chemotherapy: Subjects with glioblastoma will receive or will have received treatment with chemotherapy and radiation per the standard of care.
9
Total11

Baseline characteristics

CharacteristicMetastatic Melanoma to the Brain (Cohort A)TotalPrimary Brain Tumor (Cohort C)Primary Brain Tumor (Cohort B)
Age, Continuous80 years59 years58 years65 years
Ethnicity (NIH/OMB)
Hispanic or Latino
0 Participants1 Participants1 Participants0 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
1 Participants9 Participants7 Participants1 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
0 Participants1 Participants1 Participants0 Participants
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
Asian
0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
Black or African American
0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
More than one race
0 Participants1 Participants1 Participants0 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
Unknown or Not Reported
0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
White
1 Participants10 Participants8 Participants1 Participants
Region of Enrollment
United States
1 participants11 participants9 participants1 participants
Sex: Female, Male
Female
0 Participants2 Participants1 Participants1 Participants
Sex: Female, Male
Male
1 Participants9 Participants8 Participants0 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
EG002
affected / at risk
deaths
Total, all-cause mortality
0 / 00 / 00 / 0
other
Total, other adverse events
0 / 00 / 00 / 0
serious
Total, serious adverse events
0 / 00 / 00 / 0

Outcome results

Primary

Change in PBR Uptake (Changes in PBR Uptake by PET)

The change in PBR uptake in arms cohorts A and B from baseline to the start of cycle 4 for metastatic melanoma patients or cycle 3 for glioblastoma patients. The 18-kDa translocator protein (TSPO) is a protein that is expressed in mitochondria and is particularly prominently expressed by activated microglia, infiltrating macrophages, and reactive astrocytes. Thus, it is a marker of neuro-inflammation. PBR28 is a second generation PET tracer that binds to TPSO. PBR28 uptake was quantified using the standardized uptake value (SUV), which is the ratio of activity per unit volume of the region of interest (ROI) compared to cerebellum. Higher values indicate increased uptake in the ROI.

Time frame: At baseline and 3 to 4 months post baseline

Population: Only a baseline measurement was taken for the 1 patient in cohort A. Change in PBR was therefore not possible to calculate for that patient. PBR PET was only assessed once in cohort C and is reported separately.

ArmMeasureGroupValue (MEDIAN)
Primary Brain Tumor (Cohort B)Change in PBR Uptake (Changes in PBR Uptake by PET)Before immunotherapy1.301 percent change from baseline
Primary Brain Tumor (Cohort B)Change in PBR Uptake (Changes in PBR Uptake by PET)During immunotherapy1.1219 percent change from baseline
Primary

Median PBR Uptake

The median PBR28 uptake as measured by positron emission tomography (PET) following chemo-radiation. The 18-kDa translocator protein (TSPO) is a protein that is expressed in mitochondria and is particularly prominently expressed by activated microglia, infiltrating macrophages, and reactive astrocytes. Thus, it is a marker of neuro-inflammation. PBR28 is a second generation PET tracer that binds to TPSO. PBR28 uptake was quantified using the standardized uptake value (SUV), which is the ratio of activity per unit volume of the region of interest (ROI) compared to cerebellum. Higher values indicate increased uptake in the ROI.

Time frame: At the time of suspected pseudo-progression (up to 4 weeks after consent)

ArmMeasureValue (MEDIAN)
Metastatic Melanoma to the Brain (Cohort A)Median PBR Uptake0.8172 Ratio

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026