Combined Modality Radioimmunotherapy For Hormone Refractory Metastatic Prostate Cancer With Two Cycles Of Escalating Dose 90Y-DOTA-Peptide-m170 And Fixed, Low Dose Paclitaxel With Blood Stem Cell Support And Cyclosporin For HAMA Suppression

OBJECTIVES:

• Determine the maximum tolerated dose of yttrium Y90 monoclonal antibody m170 administered with paclitaxel and cyclosporine followed by autologous peripheral blood stem cell transplantation in patients with hormone-refractory metastatic prostate cancer.
• Determine the preliminary efficacy of this regimen in these patients.

OUTLINE: This is an open-label, dose-escalation study of yttrium Y 90 monoclonal antibody m170 (Y90 MOAB m170). Patients are assigned to one of four cohorts.

After the first occurrence of hematologic dose-limiting toxicity in a patient, all subsequent patients receive filgrastim (G-CSF) subcutaneously (SC) beginning 4 days prior to undergoing apheresis and continuing until 6 million CD34+ cells/kg are collected. After 2 patients in a cohort group experience hematologic dose-limiting toxicity, subsequent patients undergo autologous peripheral blood stem cell (PBSC) transplantation.

• Cohort I: Patients receive unlabeled monoclonal antibody (MOAB) m170 IV over 5 minutes followed by a tracer dose of indium In 111 monoclonal antibody m170 (In111 MOAB m170) IV over 5-10 minutes on day 0 and unlabeled MOAB m170 IV followed by Y90 MOAB m170 IV on day 7. Patients also receive oral cyclosporine every 12 hours on days -3 to 25. Patients may undergo autologous PBSC transplantation on day 21 and receive G-CSF SC daily beginning on day 21 and continuing until blood counts recover.
• Cohort II: Patients receive treatment as in cohort I. Patients also receive paclitaxel IV over 3 hours on day 9.
• Cohort III and IV: Patients receive treatment as in cohort I without In111 MOAB m170. Patients also receive paclitaxel as in cohort II.