Progress in the treatment of a neglected infectious disease: visceral leishmaniasis.

Visceral leishmaniasis (kala-azar) is a disseminated intracellular protozoal infection. Most cases (90%) occur in the rural regions of five countries: India, Sudan, Nepal, Bangladesh and Brazil. As with other infectious diseases embedded in high-level poverty, developing and/or delivering new treatments for visceral leishmaniasis had been painfully slow or nonexistent. However, despite persistent unresolved obstacles (e.g., drug affordability), renewed interest in visceral leishmaniasis and numerous successful treatment trials have combined to turn a therapeutic corner in the past 5 years, yielding new alternatives to conventional pentavalent antimony. Advances include the use of low-cost generic pentavalent antimony, rediscovery of amphotericin B, short-course regimens via lipid formulations of amphotericin B, retesting injectible paromyomycin and, of clear-cut importance, identifying miltefosine (Impavido, Zentaris) as the first effective oral therapy for this neglected disease.