Lonidamine versus high-dose tamoxifen in progressive, advanced renal cell carcinoma: Results of an ongoing randomized phase II study

: Sixty patients with metastatic renal cell carcinoma were entered into an ongoing randomized phase II study with lonidamine, 350 mg/m2 orally daily (arm A) and high dose tamoxifen, 150 mg/m2 orally daily for 6 months, afterwards 50 mg/m2 (arm B), until tumor progression. All patients had measurable disease and documented tumor progression prior to treatment. There were 1 complete and 1 partial remission among 19 evaluable patients in arm A (10.5%) and 2 complete and 1 partial remission among 25 evaluable patients (12%) in arm B. Objective responses were observed in pulmonary, nodal, and cutaneous metastases. In addition, in 63% and 64% tumor progression could be stopped in arm A and B, respectively. Median response duration was 100 days (range, 20-361) in arm A and 150 days (range, 28-355) in arm B. One year survival rate was 37.5% with lonidamine and 35% with tamoxifen. In arm A patients with tumor progression within 12 weeks after diagnosis of metastatic disease survived significantly shorter than patients with a longer interval (P less than 0.05). Nephrectomy or number and localization of metastatic sites failed to significantly influence probability of remission or survival. Toxicity was mostly mild to moderate. Four patients in the lonidamine arm had to discontinue treatment because of intolerable myalgias, which were immediately reversible. These data suggest that lonidamine and high-dose tamoxifen are moderately effective in widespread renal cell carcinoma where treatment intention is palliative.