Phase II trial of CI-980 in patients with disseminated malignant melanoma and no prior chemotherapy. A Southwest Oncology Group study.

Malignant melanoma is increasing in frequency at a rapid rate in the United States. Metastatic disease is chemoresistant with DTIC considered the most active single agent. CI-980 is a synthetic mitotic inhibitor that blocks the assembly of tubulin and microtubules. It has shown cytotoxic activity against a broad spectrum of murine and human tumor cell tines. CI-980 can cross the blood brain barrier, is effective when given orally or parenterally, and is active against multidrug resistant cell lines overexpressing P-glycoprotein. In this trial, patients with disseminated melanoma with measurable disease, SWOG performance status of 0-1, no prior chemotherapy or immunotherapy for metastatic disease, and adequate hepatic and renal function, were enrolled. Treatment with CI-980 was given by 72 h continuous i.v. infusion at a dose of 4.5 mg/m2/day, days 1-3 every 21 days. Twenty-four patients were registered on this study with no patients ineligible. They ranged in age from 33-78 with performance status of 0 in 15 patients and 1 in 9 patients. Nineteen patients had visceral disease with 12 having liver involvement. There were no confirmed responses. The overall response rate was 0% (95% CI 0%-14%). The median overall survival is eleven months (95% CI 4-14 months). The most common toxicities were hematologic and consisted of leukopenia/granulocytopenia and anemia, with nausea/vomiting and malaise/fatigue/weakness also frequent. CI-980 administered at this dose and schedule has insufficient activity in the treatment of disseminated malignant melanoma to warrant further investigation.