FIND, WHO and partners create framework for test that predicts progression of TB
29 November 2017: The End TB Strategy introduced by the World Health Organization (WHO) and adopted by the World Health Assembly aims to reduce TB related deaths by 95% and new TB infections by 90% by 2035. Approximately one quarter to one third of the world’s population is currently infected with the M. tuberculosis bacteria and the risk of developing an active form of the disease among infected individuals is between 5 and 15 percent.
The ambitious targets of the End TB Strategy cannot be reached
without addressing the diagnosis and treatment of latent TB
infection (LTBI), an asymptomatic non-contagious form of the
disease. A key component of the strategy to eliminate TB is the
development of novel diagnostics that help predict whether or
not LTBI will progress to active TB, or to detect incipient TB.
Incipient TB is defined as LTBI that is very likely to develop
into the active form of the disease within a short period of
time. A diagnostic solution that could detect incipient TB would
identify patients with LTBI that would benefit most from
preventive therapy.
While current tests can detect
whether someone has been exposed to TB, they are unable to
predict whether an individual will progress to active TB in the
future. It is unrealistic to treat all of the approximately 2
billion infected individuals, as the necessary resources are not
available and most cases will never progress to an active form
of the disease. A test that is able to detect incipient TB or
accurately predict the development of the disease at various
stages is therefore urgently needed.
A consensus
meeting and subsequent published report for the
“Development of a Target Product Profile (TPP) and
framework for evaluation for a test for predicting progression
from tuberculosis infection to active disease”
recently took place, led by WHO and FIND. This document provides
guidance to test manufacturers, researchers and research funders
on the nature and significance of LTBI and the relevant
implications for the development of new diagnostic
technologies.
The report presents a TPP for a test of
progression of LTBI that defines key specifications, such as
intended use, pricing, performance and operational
characteristics. It also provides a framework for the evaluation
of tests that predict progression to active TB using standard
study designs and evaluation protocols.
According to
the report, the ideal test would be able identify incipient TB
by detecting an immune response signature within the individual
that indicates the progression of the disease. In support of
these efforts, FIND will continue to collect suitable specimens,
coordinate clinical trials, collaborate with researchers to
model country-level data and estimate impact, and provide
support tools for test development and implementation.
FIND’s work in this area is supported by the Australian
government and UK aid from the UK government.
Source:
FIND
