Researchers in the UK and US have created a more precise method to detect tuberculosis (TB) using positron emission tomography (PET).
The team, consisting of experts from the Rosalind Franklin Institute, the Universities of Oxford and Pittsburgh, and the National Institutes of Health in the USA, have introduced a new radiotracer that is absorbed by live TB bacteria within the body. Radiotracers are radioactive substances that emit radiation, detectable by scanners to generate 3D images.
The new radiotracer, named FDT, allows PET scans to accurately identify the active areas of the disease in a patient’s lungs for the first time.
Following successful pre-clinical trials without any adverse effects, the researchers are preparing for Phase I trials involving human subjects.
Published in Nature Communications, this research received funding from the Gates Foundation and UK Research and Innovation.
Currently, two primary methods are employed for TB diagnosis: testing for TB bacteria in saliva or conducting a PET scan to detect lung inflammation using the standard radiotracer FDG.
A saliva test may yield negative results prematurely, potentially leading to patients stopping treatment too soon, even before the disease is completely eradicated from the lungs.
While inflammation scanning aids in gauging disease severity, it lacks specificity to TB as other conditions can also trigger inflammation. In some cases, inflammation persists in the lungs post-TB bacteria elimination, prolonging unnecessary treatment.
The new method developed by the researchers is more precise as it utilizes a carbohydrate specific to TB bacteria processing only.
An advantage of this new method is its basic requirements of standard radiation control and PET scanners at hospitals, which are increasingly common worldwide. The creation of the new molecule from FDG involves a simple process using enzymes developed by the researchers, enabling production without the need for specialized facilities or expertise, making it feasible for countries with limited healthcare systems in low- and middle-income regions where over 80% of global TB cases occur.
In 2021, TB affected 10.6 million individuals with 1.6 million deaths, making it the second most lethal infectious disease after COVID-19.
Professor Ben Davis, Director of Science at the Franklin’s Next Generation Chemistry group, led this research. He emphasized the importance of accurate identification of active TB for proper treatment with antibiotics.
Dr. Clifton Barry III from the National Institute of Allergy and Infectious Diseases highlighted that FDT enables real-time assessment of TB bacteria viability in treated patients, revolutionizing clinical trials for new medications.
