OUTLINE: This is a randomized, open label, multicenter study. Patients are stratified by performance status (70-80% vs 90-100%), baseline present pain intensity score (2.0 vs greater than 2.0), and hemoglobin level (less than 12.0 g/dL vs at least 12.0 g/dL). Patients enter one of two treatment arms: Arm I: Patients are premedicated with an IV 5-HT3 reuptake inhibitor (i.e., odansetron) then receive mitoxantrone IV on day 1. Twice daily oral prednisone therapy begins on day 1 and continues throughout study treatment. Treatment repeats every 21 days for 4 courses. Arm II: Patients are premedicated with an IV 5-HT3 reuptake inhibitor as in arm I. Patients receive mitoxantrone and prednisone therapy as in arm I. Additionally, beginning on day 1 patients receive leflunomide (SU101) IV over 4-5 hours weekly for 12 weeks. The SU101 infusions shall precede mitoxantrone infusions. Patients receive a maximum of one year therapy with SU101; mitoxantrone therapy may be administered up to a maximum dose of 140/m2. Quality of life is assessed at baseline, day 8, day 21, and then every 3 weeks thereafter until study completion. Patients are followed at least every 2 months.