New tuberculosis drugs in development.

Over the past 50 years, no new drug classes have been introduced to treat tuberculosis. Tuberculosis (TB) kills nearly two million people a year mainly in the poorest communities in the developing world. It afflicts millions more. About one third of the world's population is silently infected with TB that may erupt into disease with increased age or suppression of the immune system. Nearly nine million new active cases develop every year. The World Health Organization (WHO) declared the disease a global emergency as long ago as 1993. Although huge efforts in public health control have reduced the disease burden within most established market economies, in Africa and Asia the epidemic continues to accelerate, particularly fueled by the HIV epidemic. Furthermore, resistance to the standard drugs isoniazid and rifampicin is increasing worldwide. Since the 1990s, mycobacteria have emerged with resistance patterns rendering all currently available antibiotics ineffectual. The pharmaceutical industry has mostly abandoned TB drug development due to perceived non-profitable consumer market and the diminishing number of companies engaged in anti-infective research. The public sector and infectious disease researchers have responded to advance fundamental science and to create new chemical entities as early drug candidates. With support from research funding agencies, philanthropic donors, and the STOP-TB Partnership, new chemical tools and new approaches to effectively implement TB control programs are evolving. Advanced preclinical development and strategies for Phase III clinical trials remain gap areas that will require additional engagement from all sectors.