If the MTD has been exceeded by dose escalation and only one cohort with no observed toxicities was tested at the previous dose level, an additional cohort of 3 patients will be tested at the previous dose level. Thus, six patients must be treated at the dose declared the MTD. In the unlikely event that 150 mg/day of hydralazine, the starting dose, produces two or more DLTs, the daily dose of hydralazine will be reduced by 50mg to100 mg/day. If two or more toxicities are observed at this reduced dose level, the study will be stopped and the phase II study will not be performed.