Alignment of new tuberculosis drug regimens and drug susceptibility testing: a framework for action

Abstract

New tuberculosis drug regimens are creating new priorities for drug susceptibility testing (DST) and surveillance. To minimise turnaround time, rapid DST will need to be prioritised, but developers of these assays will need better data about the molecular mechanisms of resistance. Efforts are underway to link mutations with drug resistance and to develop strain collections to enable assessment of new diagnostic assays. In resource-limited settings, DST might not be appropriate for all patients with tuberculosis. Surveillance data and modelling will help country stakeholders to design appropriate DST algorithms and to decide whether to change drug regimens. Finally, development of practical DST assays is needed so that, in countries where surveillance and modelling show that DST is advisable, these assays can be used to guide clinical decisions for individual patients. If combined judiciously during both development and implementation, new tuberculosis regimens and new DST assays have enormous potential to improve patient outcomes and reduce the burden of disease.

Tuberculosis diagnostics: which target product profiles should be prioritised?

“…But which new TB diagnostics should they invest in, and what is the potential market size for these products? Stakeholders have expressed a need for different products, including a test for childhood TB [5], a simple point-of-care-test for active pulmonary TB [6], a molecular smear replacement test [7], DST for expected new drug regimens [8], predictive biomarkers for latent TB infection (LTBI) [9], and treatment monitoring [10].…”

Anti-Tuberculous Drugs and Susceptibility Testing Methods: Current Knowledge and Future Challenges

“…Additionally, smear microscopy does not provide any information about drug resistance, so most patients are put directly onto a standardized first-line regimen without any knowledge of drug susceptibility. However, the increasing awareness of MDR-TB has drawn greater attention to the need for DST, with the initial focus on R DST for the diagnosis of MDR-TB [34].…”

Molecular diagnosis of tuberculosis: we need solutions that span the healthcare value chain

“…New forthcoming TB drug regimens will require adequate companion diagnostics to ensure timely completion of the 'test and treat' approach [18]. To this end, Cepheid Inc. is developing another cartridge, the Xpert XDR cartridge that will provide drug resistance information for additional key drugs (isoniazid, fluoroquinolones, and aminoglycosides).…”