- Phase I (completed 10/2/2001): Cohorts of 3-6 patients from stratum II receive escalating doses of tipifarnib until the maximum tolerated dose (MTD) is determined. The MTD is defined as the dose preceding that at which 2 of 3 or 2 of 6 patients experience dose-limiting toxicity. (Stratum II in the phase I portion of this study closed to accrual effective 07/16/2001.)