Actiphage blood test enters human TB trials

UK researchers hope new rapid blood test could improve TB screening.

A new blood test for tuberculosis (TB) could, for the first time, enable screening of patients at an early stage of infection. The simple Actiphage blood test is being investigated in a clinical trial by researchers from the University of Leicester and PBD Biotech - with results due to be announced in May.

Despite recent reductions, England still has one of the highest rates of TB in Western Europe. TB is a serious bacterial infection, which can be life threatening if not properly treated with antibiotics. Pulmonary TB of the lungs or throat is contagious, but TB can affect any part of the body. While TB cases have been declining overall in the UK, the rate of TB in the most deprived areas remains more than seven times higher than in the least deprived.

One of the biggest challenges in human TB is rapid early diagnosis. Traditional tests rely on sputum to detect the infection but almost half of all people with pulmonary TB are unable to produce sputum, particularly in early disease. No blood tests presently exist to help with TB diagnosis. This contributes to delays in diagnosis and starting treatment and promotes transmission in the community.

Actiphage, developed by PBD Biotech, is an alternative to bacterial culture that was originally used for the detection of human TB (under the FastPlaque brand) but was only suitable for use on sputum. Now technology has been optimised so it can detect the presence of the mycobacteria in blood in just six hours. This means it may help to improve the speed and reliability of diagnosis for all TB patients and avoid the need for some patients to have more invasive tests performed.

The clinical trial of the new Actiphage test will involve a cohort of patients with both latent and active TB at Leicester’s Hospitals.

Dr Pranab Haldar from the University of Leicester, one of the UK’s leading TB research groups, is the lead clinician on the trial and commented: “Many think of TB as a disease of the past and yet it is continuing to affect people, particularly in vulnerable communities across the country. Despite having a modern and well-equipped NHS, a third of patients still wait more than three months after symptoms begin to have a diagnosis made and treatment started.

“Through this trial we are keen to explore the potential of Actiphage to provide better insights into M. tuberculosis infection and determine how the test can support and contribute to tackling this public health problem in the UK as well as internationally.”

Dr Berwyn Clarke, CEO of PBD Biotech, said: “Actiphage is the first sensitive, specific and speedy blood test for Mycobacteria. Its effectiveness has been proven in TB trials with other species, so it is an incredibly exciting opportunity to be working with one of the world’s leading human TB research groups to investigate its potential as a transformational tool in human health.”

The findings will be announced at the American Thoracic Society (ATS) International Conference in May 2019.