Phase II study with interferon alpha-2a and 13-cis-retinoic acid in patients with metastatic renal cell carcinoma - A trial of the phase II study group of the Association for Medical Oncology of the German Cancer Society

Background: Due to promising results in earlier clinical studies, a confirmatory phase II clinical trial of interferon alpha-2a (IF) and 13-cis-retinoic acid (RA) was conducted in patients with metastatic renal cell carcinoma (mRCC). Patients and Methods: 29 previously untreated patients with mRCC were treated. IF was given subcutaneously daily at 3 MU and escalated to 6 and 9 MU if tolerated. The RA dose was 1 mg/kg/day. The treatment was given over a period of 12 weeks, a staging procedure was performed every 6 weeks within the first half year and, thereafter, in 3-month intervals until progressive disease was documented. Results: 27 patients were eligible, 24 patients were evaluable for tumor response. 2/24 patients achieved a major response (2 partial responses), 9/24 had a treatment failure (9 progressive diseases), and 13/24 showed a status-idem situation (13 no-change cases). Myelotoxicity, nausea, epidermal toxicity, loss of appetite and weight loss were considerable and occurred inmost of the patients. Conclusions: IF and RA showed less antitumor activity than had been anticipated in advanced RCC. The proportion and the nature of response as well as the toxicity pattern suggest the deletion of this combination from the therapeutical repertoire of medical oncologists.