PHASE-II STUDY OF PACLITAXEL IN PATIENTS WITH PREVIOUSLY TREATED OSTEOSARCOMA AND ITS VARIANTS

BACKGROUND. Patients with osteosarcoma and its variants who did not re spond to standard chemotherapy including doxorubicin, ifosfamide, cisp latin, and high dose methotrexate were treated with paclitaxel so that its therapeutic activity in these patients could be determined. METHO DS. We conducted a Phase II study of paclitaxel in patients with conve ntional osteosarcoma (10), malignant fibrous histiocytoma of the bone (3) and dedifferentiated chondrosarcoma (2) whose disease had progress ed after prior standard chemotherapy including doxorubicin, cisplatin, ifosfamide, and high dose methotrexate. Paclitaxel was administered a l a starting dose of 175 mg/m(2) as a 24-hour infusion with Standard p remedication every 21 days or upon hematologic recovery (absolute gran ulocyte count [AGC] > 1500/mu l, platelets > 100,000/mu l). Neupogen w as not used routinely. The study was conducted based on a two-stage de sign. A total of 17 patients were entered into the protocol. Two were ineligible since they had Ewing's sarcoma. Responses were assessed rad iographically and pathologically when feasible, using standard criteri a. RESULTS. Fifteen eligible patients were treated in the first stage of the study. Median age of the patients was 31 years (range, 19-61 yr s). There were 8 females and 7 males with a Zubrod performance status of 0 or 1. One patient achieved a mixed response and 14 developed prog ressive disease. Median AGC nadir was 0.3, on Day 13, lasting 5 days. Median platelet nadir was 134, on Day 8. There were no Grade III or IV nonhematologic toxicities and no deaths related to treatment. CONCLUS IONS. Paclitaxel, at this dose and schedule, is well tolerated but ina ctive in this patient population. (C) 1996 American Cancer Society.