Tackling drug-resistant tuberculosis: we need a critical synergy of product and process innovations.

The End TB Strategy diagnostic pillar calls for access to high-sensitivity diagnostic testing and universal rapid drug susceptibility testing (DST). The recommended diagnostic technologies available in low and middle-income, high-burden countries for multidrug-resistant tuberculosis (MDR-TB) are essentially limited to Xpert MTB/RIF and MTB/RIF Ultra assays, culture DST and the line-probe assays. The primary reasons for slow scale-up are insufficient political will, and therefore, insufficient funding for qualified human resources, and safe laboratory and health system infrastructure. Innovative approaches to enable the private health sector to provide high-quality diagnosis are also needed. The Essential Diagnostics List provides impetus and a standard benchmark for the rational implementation of MDR-TB diagnostics, but the epidemic will ultimately only be favorably impacted by complete end-to-end solutions to patients that address the complete cascade of care, including patient-centered diagnosis and treatment of TB and MDR-TB, management of comorbidities and social protection. By scaling up access to the currently available diagnostics, we lay the groundwork for future innovations for rapid accurate diagnosis of MDR-TB, which in turn will bring us closer to meeting the targets in the End TB Strategy.