This paper is on dangerous human experimentations with drugs against trypanosimiasis carried out in the former German colonies of German East Africa and Togo. Victory over trypanosomiasis could not be achieved in Berlin because animals were thought to be unsuitable for therapeutic laboratory research in the field of trypanosomiasis. The colonies themselves were necessarily chosen as laboratories and the patients with sleeping sickness became the objects of therapeutical and pharmacological research. The paper first outlines Robert Koch's trypanosomiasis research in the large sleeping sickness laboratory of German East Africa and then focuses on the escalating human experiments on trypanosomiasis in the German Musterkolonie Togo, which must be interpreted as a reaction to the starting signal given by Robert Koch in East Africa.