The new Treatment Action Group (TAG) Pipeline Report Tuberculosis Diagnostics published in November 2022, highlights Actiphage® as the only blood-based diagnostic in development for subclinical tuberculosis that directly detects mycobacteria and provides an early indication of disease progression. The report provides an annual review of research and development of innovations for diagnosing, preventing, treating, and curing tuberculosis (TB).
Non-sputum TB diagnostic top priority in TAG Pipeline report
The TAG Pipeline Report states that TB deaths have increased since 2019 due to insufficient access to quality TB testing and linkage to treatment. One of TAG’s top priorities is the need for “TB Screening and Triage Tools.” It states that there is a critical need for better diagnostic technologies to screen and triage for TB, especially for subclinical TB, prior to the onset of symptoms.
The TAG report also states the need to develop new non-sputum TB molecular diagnostics as a top priority, given that not all people can produce sputum, particularly children and those living with HIV.
Actiphage detects subclinical mycobacterial infection
Actiphage was shown to be the only blood-based, non-sputum molecular diagnostic technology for detecting mycobacteria in the report.
Actiphage uses a bacteriophage to detect subclinical mycobacteria infection in the blood, which has been shown to be an early indication of disease progression. It lyses the bacteria and releases the DNA for qPCR analysis.
Additional opportunities for further genotype analysis using the Actiphage test may be possible.
Actiphage meets WHO Target Product Profile
Actiphage is a highly sensitive and specific early TB screening test that meets the optimal WHO Target Product Profile (TPP) performance criteria (1) for diagnosing Incipient TB and for predicting progression to active TB.
Direct detection of bacteraemia offers significant benefits over antigen-based diagnostics such as Interferon-Gamma Release Assays (IGRA), which rely on the host response to infection. As many immune-compromised individuals will not produce an antigen response.
In studies, Actiphage has demonstrated early diagnosis of subclinical TB and evidence of disease progression as a blood-based diagnostic. Actiphage has clear advantages of a rapid, low-cost assay that offers a microbiological diagnosis in the absence of sputum. (2,3)
In clinical trials
Jane Theaker, CEO of PBD Biotech, the developer of Actiphage, says: “The TAG-Pipeline report provides a very useful overview of the priorities for TB diagnosis and the strengths and limitations of diagnostics in the pipeline.
“Promising clinical trials of Actiphage and our recent funding round are accelerating development of this non-sputum-based diagnostic, which is directed at meeting the WHO Target Product Performance criteria for detecting Incipient TB and disease progression to active TB.
“We are in discussion with companies that see the potential for Actiphage as a companion diagnostic for new drug development as well as an early-stage diagnostic for disease progression.”
Treatment Action Group (TAG) is an independent, activist, and community-based research and policy think tank working to expand and accelerate vital research and effective community engagement with research and policy institutions to end HIV, tuberculosis (TB), and hepatitis C virus (HCV)
PBD Biotech Limited, located in Birmingham, UK, specialises in the use of novel phage-based technology for the detection of tuberculosis and related mycobacterial diseases in the fields of in-vitro diagnostics.
The full 2022 TAG Pipeline Report on Tuberculosis Diagnostics can be accessed at https://www.treatmentactiongroup.org/resources/pipeline-report/2022-pipeline-report/
References
- Development of a Target Product Profile (TPP) and a framework for evaluation for a test for predicting progression from tuberculosis infection to active disease
- A novel, high-sensitivity, bacteriophage-based assay Identifies low-level mycobacterium tuberculosis bacteremia in immunocompetent patients with active and incipient tuberculosis. Verma, R, Swift, B, et al. CID 2020:70
- A novel bacteriophage-based assay stratifies tuberculosis risk in recent household contacts of pulmonary tuberculosis: A prospective observational cohort study. Kim, J et al. Abstract 03734, ECCMID 2022
