OUTLINE: This is a dose escalation study. Patients receive oral SR-45023A twice daily for 14 days, followed by 7 days rest. On day 14 of course 1, patients receive only one dose of therapy due to pharmacokinetic sampling. Treatment continues every 21 days in the absence of disease progression or unacceptable toxicity. Cohorts of 3-6 patients receive escalating doses of SR-45023A until the maximum tolerated dose (MTD) is reached. The MTD is defined as the dose preceding that at which 2 of 6 patients experience dose limiting toxicity. Patients are followed until death.