There is a great need for new medicines for treating tropical disease. Even today, tropical parasitic diseases such as malaria, leishmaniasis, African sleeping sickness (HAT) or Chagas disease still represent a major health threat for much of the world's population. They lead to millions of deaths per year and massive socio-economic effects in many countries. New medicines should be focused on the needs of target patients, and be suitable for use in the field. They need to be cost-effective, orally bio-available and stable under extreme conditions of heat and humidity.