Phase II trial of 10-Edam in patients with advanced colorectal carcinoma

10-Edam (10-ethyl-10-deaza-aminopterin), an antifolate derivative, was administered to 14 chemotherapy-naive patients with advanced colorectal carcinoma. The drug was given weekly by intravenous route at an initial dose of 80 mg/m2, with escalation or attenuation according to tolerance. Mucositis was dose limiting and occurred in 11 of 14 patients (78.6%). Removal from the study was required in one patient due to progressive pulmonary fibrosis that was histologically identical to methotrexate-induced lung damage. Toxicity was otherwise mild to moderate and included diarrhea, constipation, abdominal discomfort, anorexia, nausea/vomiting, rash, and fatigue. There were no responses to 10-Edam in this study, 95% confidence interval (0-0.23). Stable disease was achieved in four patients; the remaining 10 patients demonstrated progression within 9 weeks of initiating systemic therapy. 10-Edam employed at this dosage and schedule was not effective as a treatment against advanced colorectal carcinoma.