A phase I study of a new nucleoside analogue, OSI-7836, using two administration schedules in patients with advanced solid malignancies.

PURPOSE: To investigate the safety, tolerability, and pharmacokinetic profile of the novel nucleoside analogue OSI-7836 in patients with advanced solid malignancies. EXPERIMENTAL DESIGN: OSI-7836 was initially given as a 60-minute i.v. infusion on day 1 every 21 days. In view of its dose-limiting toxicities, the administration time was amended to a 5-minute bolus, and subsequently, the schedule was amended to weekly for 4 weeks followed by a 2-week rest. Blood and urine samples were collected for pharmacokinetic studies. Analyses of cytokines and lymphocyte subsets were added later in the study to elucidate a mechanism for the severe fatigue and lymphocyte depletion observed in earlier patients. RESULTS: Thirty patients received a total of 61 treatment cycles. Fatigue was the main dose-limiting toxicity. Maximum-tolerated dose was defined as 300 mg/m2 in the 60-minute infusion, (three times per week) schedule; 400 mg/m2 in the 5-minute bolus infusion, (three times per week) schedule; and 100 mg/m2 in the weekly schedule. Other common toxicities were nausea, vomiting, rash, fever, and a flu-like syndrome. There were no clinically significant hematologic toxicities. Following the initial dose, OSI-7836 was eliminated from plasma with a median (range) elimination half-life of 48.3 minutes (22.6-64.8 minutes). Lymphocyte subset analysis showed a significant drop in B cell counts, which persisted to day 14 and beyond. Cytokine analysis showed significant elevations of interleukin-6 and interleukin-10 in all patients who received > or = 200 mg/m2 OSI-7836. Best response was disease stabilization in seven patients. CONCLUSION: OSI-7836 was associated with excessive fatigue, and despite changes in its schedule and duration of administration, we did not observe an improvement in its tolerability. Its potentially selective effect on B lymphocytes could be exploited in further studies in specific hematologic malignancies.

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

PURPOSE: 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. PATIENTS AND METHODS: 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. RESULTS: 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. CONCLUSION: 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.