Phase II trial of 9-nitrocamptothecin (RFS 2000) for patients with metastatic cutaneous or uveal melanoma

The camptothecin derivative 9-nitrocamptothecin (9-NC) has demonstrated clinical activity in patients with ovarian and pancreatic carcinomas. Preclinical studies have shown promising activity of 9-NC for melanoma. We have thus conducted a phase II clinical trial of 9-NC for patients with metastatic cutaneous and uveal melanoma. Twenty-eight patients were enrolled in the trial, with diagnoses evenly divided between the two types of melanoma. 9-NC was administered orally at a starting dose of 1.5 mg/m/day for 5 consecutive days of each week. No complete or partial responses were observed. Stabilization of disease was achieved in four individuals (15%) for durations of 3, 4, 6 and 8 months. Hematologic toxicity was moderate. Gastrointestinal side effects were common with 43% of the patients experiencing grade 3 or 4 diarrhea and 18% reporting grade 3 or 4 vomiting. In contrast to other 9-NC clinical trials, no patients developed chemical cystitis with gross hematuria. We conclude that, in keeping with the general chemoresistance of melanoma, 9-NC at the dose and schedule studied in this trial is significantly toxic and is not active for metastatic melanoma of cutaneous or uveal origin.