A phase 1 study investigated the first small molecule PPARγ inverse agonist for the treatment of advanced solid tumors.[1] Research has demonstrated an acceptable safety profile of this substance in patients.[1] The drug showed preliminary activity against tumors, especially in urothelial carcinoma.[1] PPARγ inverse agonists represent a new approach in antitumor therapy, which is different from PPAR agonists investigated so far.[1] The results of this study are the first clinical evidence of the effectiveness of this type of drug in people with advanced tumors.[1] The safety profile was good enough for the study to continue with further phases of research.[1]