Randomized phase II study comparing thalidomide with medroxyprogesterone acetate in patients with metastatic renal...

To investigate escalating doses of thalidomide compared with medroxyprogesterone in patients with metastatic renal cell carcinoma (RCC), who had either progressed after first-line immunotherapy or who were not suitable for immunotherapy.

Thalidomide was started at 100 mg/d orally (PO) and escalated by 100 mg/d every 2 weeks to the maximum dose of 400 mg/d. Medroxyprogesterone was given at a fixed dose of 300 mg PO daily.

Sixty patients were entered (thalidomide:medroxyprogesterone = 29:31; median age, 59 [thalidomide], 60 [medroxyprogesterone]; No. of patients assessable for response, 22 [thalidomide], 26 [medroxyprogesterone]). In the thalidomide arm, there was no objective response seen. The best response was SD in three patients lasting 5+, 6+, and 12 months, respectively. All patients in the medroxyprogesterone arm progressed. There was no difference in overall survival between the two arms; median survival in the thalidomide arm was 8.2 months compared with 4.8 months in the medroxyprogesterone arm (P = .62). Hazard ratio was 0.88 (95% CI, 0.67 to 1.94). Median duration of treatment was 73 days (range, 14 to 364 days) in the thalidomide arm, and 84 days (range, 7 to 175 days) in the medroxyprogesterone arm. The high incidence of toxicity in the thalidomide arm, mainly somnolence, constipation, fatigue and paraesthesia, meant that only 30.8% of patients were able to tolerate the maximum dose of 400 mg/d of treatment.

Thalidomide is not superior to medroxyprogesterone acetate in patients with metastatic RCC. Its risk/benefit ratio does not favor its use in this patient population.