HRH3 and obesity due to melanocortin 4 receptor deficiency: Unfortunately, these promising results could not be translated to human obesity treatment, since all investigated drug candidates either raised safety concerns or were ineffective in clinical studies.7 However, there is evidence that the simultaneous antagonism of MCHR1 and histamine H3 receptor (H3R) might result in a synergistic effect that could be beneficial in obesity treatment.8 Also, we recently found three ligands that bind both receptors in the nanomolar activity range validating this target pair for rational multi‐target drug design campaigns.9