Results of a 2-arm Phase II study of 9-nitrocamptothecin in patients with advanced soft-tissue sarcomas

The authors conducted a 2-arm Phase II trial of 9-nitrocamptothecin (9-NC), an oral topoisomerase I inhibitor, to define response rates in patients with gastrointestinal (GI) leiomyosarcomas and other soft-tissue sarcomas (STS).

Patients were required to provide informed consent and have measurable disease, Zubrod performance status < or = 2, and adequate organ function. 9-NC was administered orally at 1.5 mg/m(2) per day x 5 days every week. Response evaluation was performed at 8 weeks, and those with stable or responding disease continued treatment until maximal response was achieved. A total of 56 patients (30 females and 26 males) with a median age of 55 years (range, 19-79 years) were enrolled on the study. Seventeen patients were enrolled on the GI leiomyosarcoma arm; only 1 minor response, lasting < 8 weeks in a patient with liver metastases, was noted, and so this arm was terminated. Thirty-nine patients were entered on the other STS arm.

Three patients achieved a partial response (response rate, 8%) for durations of 4, 6, and 13 months, respectively. Fourteen patients had stable disease for a median of 4 months (range, 2-8 months). Two patients died of disease during the first 2 months. Four other patients required hospitalization for nausea, vomiting, and dehydration. Other toxicities included diarrhea (36 patients, 5 with Grade 3 toxicity); fatigue (42 patients, 11 with Grade 3 toxicity); anorexia (32 patients, 1 with Grade 3 toxicity); nausea (37 patients, 2 with Grade 3 toxicity); vomiting (24 patients, 3 with Grade 3 toxicity); neutropenia (14 patients, 5 with Grade 3 toxicity); and thrombocytopenia (16 patients, 5 with Grade 3 or 4 toxicity).

9-NC is well tolerated but inactive in GI leiomyosarcomas and has minimal activity in previously treated patients with STS.