TB is also the number one killer of people with AIDS, but it is generally agreed that current TB treatments do not work well with the antiretroviral drugs used to treat HIV. New, improved TB treatments are urgently needed. However, the TB drug market lacks sufficient financial incentives to stimulate broad-based investment from pharmaceutical companies to invest in the new research required to sustain a treatment pipeline. The TB epidemic is concentrated in developing countries where drugs must be low in cost to remain accessible. It does not generate the kind of revenue streams that private companies usually deem necessary to justify the research costs and strategic risks involved in pharmaceuticals. TB Alliance was designed to be the primary instrument to fill this vacuum and to ensure that new anti-TB drugs are affordable and accessible in endemic countries.