PRIOR CONCURRENT THERAPY: Biologic therapy: No concurrent biologic therapy Chemotherapy: At least 30 days since prior cytotoxic therapy and recovered No concurrent chemotherapy Endocrine therapy: Not specified Radiotherapy: No concurrent radiotherapy to greater than 25% of skeleton Surgery: No concurrent surgery Other: At least 3 weeks since prior investigational drugs (including analgesics or antiemetics) Recovered from toxic effects of any prior therapy