Establishing Radiolabelled PSMA as a Target for Glioma Treatment

June 8, 2022 updated by: King's College Hospital NHS Trust

Dosimetry and Immunohistochemistry Study to Establish Radiolabelled PSMA as a Potential Target in Glioma Treatment

A study is being performed to observe whether a novel type of brain imaging using a technique called PET-MRI may provide useful information in the 'mapping' of adult primary brain tumours. It employs a radiolabelled molecule targeting a particular molecule called PSMA which is hypothesised to be a marker of aggression in primary brain tumours. 'Mapping' of the concentration and distribution of this molecule within brain tumours via PET-MRI may provide vital clinical information regarding the extent and timing of treatment.

Study Overview

Status

Not yet recruiting

Conditions

Detailed Description

One potential avenue of high grade glioma treatment involves a 'theranostic' radiotherapeutic approach. This consists of two stages: firstly, a particular protein expressed specifically by the tumour is radiolabelled with a targeted radioligand emitting gamma radiation, enabling confirmation of the presence, concentration and distribution of this target protein (diagnostic stage). Following this, a similar ligand is this time attached to an alpha or beta-emitter, enabling targeted tumour destruction (therapeutic stage).

There is growing, but limited, evidence that prostate specific membrane antigen (PSMA) is strongly and specifically expressed in high grade glioma and may be a potential theranostic target [Wernicke 2011, Unterrainer 2017]. It has already been used extensively as a theranostic target in metastatic prostate cancer, demonstrating safety and efficacy in this condition [Abou et al 2020].

The clinical outcomes shown in prostate cancer, along with evidence of PSMA expression in high grade glioma, led the study team to convene an Incubator Day with a group of experts to explore the possibility of developing a PSMA-targeting theranostic agent in high grade glioma. Expertise included PSMA theranostics (Prof Lewington), neuro-oncology (Dr Brazil, Guy's and St Thomas' Hospital (GSTT)), neurosurgery (Prof Ashkan, King's College Hospital (KCH)), neuropathology (Prof Al-Sarraj, KCH), neuroradiology (Dr Booth, KCH) PSMA PET imaging (Prof Gary Cook and Prof Alexander Hammers GSTT/KCL), nuclear physics (Prof Paul Marsden GSTT/KCL), and PSMA radiopharmaceutical chemistry (Prof Blowers, KCL).

It was concluded that a PSMA-targeting theranostic agent has the potential to be a safe and effective treatment for high grade glioma. The regulatory pathway should be eased enormously by the precedent of use in prostate cancer, which would obviate the need for pre-clinical studies.

This approach was conditional upon two objectives:

  1. Perform a series of five [68Ga]PSMA PET scans for dosimetry analysis and assessment of the retention of the tracer in the tumour (Using GSTT/KCL PET/MRI) prior to biopsy, at the same time as the patient's routine brain tumour imaging series. At time of recurrence a further [68 Ga]PSMA PET-MRI scan may be performed in each patient (depending on whether or not recurrence occurs during the study period) to assess for change in the standardised uptake value (SUV).
  2. Performing immunohistochemical analysis on high grade glioma specimens (prospectively in patients enrolled in this study with additional retrospective samples), in order to replicate published evidence on the expression of PSMA in such tumours, and also to demonstrate in the prospective cohort, a correlation between imaging detection of [68 Ga]PSMA and histopathological detection in stereotactic brain tumour biopsy samples (Using KCH neuropathology facilities).

Study Type

Interventional

Enrollment (Anticipated)

30

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Locations

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • Individuals of 18 years or older
  • Referred for surgery (resection or biopsy) of presumed high grade primary brain tumour (based on imaging features of aggression e.g. perfusion imaging, diffusion restriction etc.). As standard, all patients will have had a full body CT and other investigations to rule out metastatic disease (this has a very high negative predictive value).
  • Written informed consent

Exclusion Criteria:

  • Patient already enrolled in a drug trial
  • Contra-indication for MRI contrast
  • Contra-indication for radiotracer
  • Inability to give consent
  • Patient is pregnant or planning to become pregnant

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Diagnostic
  • Allocation: N/A
  • Interventional Model: Single Group Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Brain tumour patients
Patients will be those undergoing routine care of primary brain tumours. Study group patients will undergo additional PET-MRI examination and biopsies in addition to the standard of care.
For the diagnostic imaging aspect included in this pilot study, [68Ga]PSMA-11 will be used. This is a peptidomimetic agent with a covalently bound chelator (HBED-CC) that is FDA-approved in prostate cancer imaging. We will use PET-MRI to visualise a) the concentration and b) the distribution of this tracer to establish a functional map of primary brain tumour activity
All patients included in our study will undergo stereotactic surgery for biopsy/resection of the tumour as part of the standard of care at KCH. During this study we will not vary from the surgical standard of care for primary brain tumours and will only extend the surgery time due to additional stereotactic biopsies (an additional 3 biopsies increasing the time of the operation by ~30 minutes). Professor Ashkan (KCH) has defined the additional surgical risk of performing these biopsies to be ~0%, since targeted biopsies will only be taken within the tumour just before resection. The stereotactic biopsy may be targeted to areas of high [68Ga]PSMA SUV within the tumour as defined by the PET MRI scan.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Correlation of the PET-MRI PSMA signal intensity (arbitrary units) and glioma protein concentration (g/L) in a 1 x 1 x 1 cm region of interest (R value)
Time Frame: 5 years
PET-MRI signal will be recorded from different regions of interest within a glioma where stereotactic surgical biopsies taken and protein concentration determined.
5 years

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Collaborators

Investigators

  • Principal Investigator: Thomas C Booth, PhD, King's College London

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Anticipated)

August 1, 2022

Primary Completion (Anticipated)

May 1, 2027

Study Completion (Anticipated)

May 1, 2027

Study Registration Dates

First Submitted

February 21, 2022

First Submitted That Met QC Criteria

February 21, 2022

First Posted (Actual)

March 2, 2022

Study Record Updates

Last Update Posted (Actual)

June 10, 2022

Last Update Submitted That Met QC Criteria

June 8, 2022

Last Verified

June 1, 2022

More Information

Terms related to this study

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Glioma, Malignant

Clinical Trials on PET-MRI

Subscribe