IL6 and obesity due to melanocortin 4 receptor deficiency: This includes low pretreatment IL-6 levels—which were predictive for response to TCZ or to sustained success after its cessation.159 160 Apart from that, a high pretreatment CRP level was indicative of good treatment responses in patients receiving TCZ.158 Data regarding obesity and treatment response, on the other hand, were more controversial.175–177 Generally, the quality of currently available evidence is considered as being low and further studies are required to confirm the validity of these analyses.