As a prerequisite for human clinical trials, preclinical studies have to confirm tolerability of test compounds in relevant species. According to the S6 guideline for preclinical safety evaluation of biotechnology-derived pharmaceuticals, “a relevant species is one in which the test material is pharmacologically active due to the expression of the receptor or an epitope […]”. In case of biopharmaceuticals addressing human-specific target, non-human primates are often the only relevant species. A high sequence homology compared to humans allows an exceptional transferability of results obtained in preclinical studies. Here we provide the possibility to analyze test compound distribution in non-human primates in vivo, as well as ex vivo.