Purpose: Renal cell carcinoma is resistant to most chemotherapy, and only a minority of patients respond to immunotherapy. Its highly vascular nature suggests that antiangiogenesis therapy might be useful. We thus performed a phase II study of the fumigillin analog TNP-470 in previously treated patients with metastatic renal cell carcinoma.
Patients and methods: Metastatic renal cell carcinoma patients with good organ function were entered onto the study through five separate institutions. There were no exclusion criteria for prior therapy. All patients were treated at a dose of 60 mg/m(2) of TNP-470 infused over 1 hour three times per week.
Results: Thirty-three patients were enrolled. Therapy was generally well tolerated, but asthenia, fatigue, vertigo, dizziness, sense of imbalance, and loss of concentration were common and severe enough to lead to therapy discontinuation in five patients. There was only one partial response of short duration (response rate, 3%, 95% confidence interval, 0% to 16%), but six patients (18%) remained on study for 6 or more months without toxicity or disease progression.
Conclusion: Long-term therapy with TNP-470 has manageable toxicities and is feasible in patients with metastatic renal cell carcinoma but does not lead to any significant objective responses. Further studies in this population using TNP-470 schedules that produce more prolonged drug levels and clinical trial end points other than objective tumor regression may be indicated.