A phase II study of troglitazone, an activator of the PPARγ receptor, in patients with chemotherapy-resistant metastatic colorectal cancer

PURPOSE Troglitazone, a potent activator of the peroxisome proliferator-activated receptor-gamma, induces tumor differentiation in human liposarcomas and causes regression of tumors that are derived from human colon cancer cells in nude mice. We therefore assessed the efficacy of troglitazone in the treatment of metastatic colon cancer in humans. METHODS Twenty-five patients with metastatic colorectal cancer were treated with oral troglitazone. Patients were followed up for evidence of toxicity, tumor response, and survival. RESULTS The treatment was well tolerated: no grade 3/4 treatment-related toxicities were observed. However, no objective tumor responses were noted, and all 25 patients had progressive disease as their best response to therapy. The median progression-free survival time was only 1.6 months, and the median survival time was 3.9 months. DISCUSSION Troglitazone is not an active agent for the treatment of metastatic colorectal cancer.