PET imaging

PET neuroimaging, a cross-cutting theme

The MRC Neurosciences and Mental Health Board has been leading an initiative to facilitate UK positron emission tomography (PET) imaging research in the central nervous system. Radioligand PET is an essential tool in translational medicine and for aspects of new drug development, particularly drugs for neurological and psychiatric indications.

Along the translational medicine developmental pathway, PET radiotracers are used for diagnosis, as a tool for drug development and to gain a better understanding of disease biology. The main uses are:

  • Dose-finding for new agents
  • Definition of populations in terms of brain abnormalities, especially receptors and enzymes
  • As a surrogate marker for treatment effects
  • Proof of concept studies in normal volunteers or patient populations

The first ever community workshop of neuroscientists using PET imaging (PDF, 157KB) was held by the board in May 2008. The participants had never previously met as a group. Some findings of the workshop were specific to neurosciences while other findings have broader relevance for PET research in other scientific areas: primarily cancer but also cardiovascular disease.

Broadly speaking, UK strengths include:

  • World class PET expertise
  • Skill/knowledge base in the UK for world-class translational research in neurosciences
  • Strong NHS/academic partnerships and possibilities for collaboration with pharma
  • Emerging multi-centre networks for all aspects of PET

The perceived challenges for the UK are:

  • Methodology needed for efficient screening of candidate compounds and better access to libraries
  • Training, recruitment and retention of radiochemists, chemists, modellers, cyclotron engineers and people with Good Manufacturing Process (GMP) / Quality Assurance (QA) expertise
  • Limited number of GMP facilities and need for routine availability of ligands for multi-centre trials.

For PET neuroscience imaging, an important distinguishing feature is that the image is less important than the ability to obtain quantitative pharmacokinetic and pharmacodynamic data. In oncology, PET primarily supplies the image of the tumour required for diagnosis and radiochemistry.

NMHB strategy development has focused on three areas – building capacity, regulatory issues and finding the best routes for working with industry. These areas continue to be supported with an added emphasis on broadening PET research methodologies.

Building capacity

In 2015, 6 new PET/MR scanners were funded for universities across the UK: Imperial, Cambridge, Newcastle, Manchester, Edinburgh and Glasgow.  This infrastructure marks a significant increase in capacity for PET research in the UK and will foster increased networking in PET technology.

A number of awards were made under a MRC specialist postdoctoral training pilot programme in PET neuroscience. Awardees were asked to establish a NeuroPET network so that UK resources can be pooled for the common good.

More details are available on page 12 of MRC Network Jan-Feb 2010 (PDF, 1.25MB).

Regulatory issues

The MRC worked with partners from the Medicines and Healthcare products Regulatory Agency (MHRA) and the National Cancer Research Institute to provide regulatory advice and a supportive environment for PET based research in UK. As a result of these discussions, a workshop for PET imaging researchers was held in September 2010 at MRC. UK PET researchers from the neurosciences, cardiovascular sciences and cancer fields were involved. Papers produced for this meeting included a decision tree (PDF, 17KB) as to whether a clinical trial authorisation is required and some examples of study scenarios (PDF, 732KB). These documents are also available on the NCRI-PET Research Network website.

Industry issues

To advance translational research, researchers must seek ways to strengthen industry-academic collaboration in the context of international competition. After a consultative meeting with industry scientists in June 2009 possible models for academic-industry centres for PET imaging were under discussion. Imanova was announced in April 2011 and is a unique partnership between the MRC, Imperial College London, King’s College London and UCL. The partners are equal shareholders in a venture that assumed responsibility for the facilities and operations of GSK’s £47m Clinical Imaging Centre at the Hammersmith Hospital campus.

In conjunction with Imanova, the MRC is promoting the development of novel PET methodologies in research areas beyond cancer and neuroscience, such as infection, mitochondrial biology, inflammation, and cardiology. 

In essence, the MRC is seeking to facilitate better interaction between industry and academia, and expand the use of PET technology throughout the UK. The goal is to make UK PET imaging research more internationally competitive. 

For further information or queries contact Emily Gale.