Medical researchers get green light on radioactive ‘tracers’

The license, which was granted following months of strict safety testing and evaluation by the Medicines and Healthcare Products Regulatory Authority (MHRA), allows the Centre to manufacture PET (Positron Emission Tomography) tracers in its high-tech sterile facilities and administer them to human participants in clinical trials. The license is one of only a handful issued in the UK.

PET scanning produces high-resolution images of internal organs and biological processes at work by injecting trace amounts of a radioactive compound, or ‘radiotracer’, into the part of the body to be scanned. Radioactive emissions from this tracer are then recorded by detectors within the scanner, and the resulting data processed by sophisticated software to create the images.

The trace levels of radioactivity are closely monitored for the safety of the patient, and diminish after a short time.

The license means the Centre can now develop, manufacture and use more complex radiotracers, such as those derived from the element Carbon-11 (11C). These will allow researchers to measure a wide range of complex molecular events such as cancer tumour growth, cell death, psychoses and chronic pain, as well as the effect of drugs designed to treat these conditions.

Such PET studies using advance tracers look set to inspire breakthroughs in research and improve the treatment of patients. The first to be enabled will investigate a possible link between inflammation in the central nervous system (CNS) and increased risk of stroke.

Lead researcher Dr Pippa Tyrrell of the University’s School of Medicine said: “This license means we can now measure CNS inflammation in subjects we know have an increased risk of stroke*, using one of the new tracers to detect activated immune cells in their brains. Around 125,000 people are affected by stroke each year in the UK and this approach could uncover vital new evidence on the role of inflammation; helping us to understand the risk factors and potentially modulate them.”

Ian Young, Quality Manager for the Centre, said “The MHRA’s requirements are very exacting and creating the extensive quality management system which has allowed us to progress to this level has involved a huge effort from all staff.”

Its Director Professor Karl Herholz said: “The award of this license is a key strategic milestone for the Centre, as we can now progress with the molecular imaging projects it is uniquely equipped to carry out. This approach to better-understanding the mechanisms of both the brain and cancer tumours is relatively under-explored, and we are very excited about its potential to inspire breakthroughs and improve patient treatments.”