Methyl-GAG in patients with malignant neoplasms: a phase I re-evaluation.

Methyl-GAG was given to 71 patients with advanced malignancies as a weekly brief infusion (30-120 minutes) or as a biweekly 24- or 120-hour infusion. Mucositis (stomatitis, pharyngitis, esophagitis, and, rarely, inflammation of other mucous membranes) was dose-limiting in all three schedules. Generalized fatigue, malaise, myalgia, dysesthesias, nausea, and vomiting were more frequent in the brief-infusion schedule. Myelosuppression was mild and not dose-related. Fever, ventricular arrhythmias, skin rash, tender swelling of the palms, neuropathy, and paralytic ileus were rare. Toxicity was increased in patients with renal insufficiency or "third-space" fluid but was not increased by hepatic dysfunction. Cumulative and overlapping toxicity was evident only in the weekly schedule. Higher doses of methyl-GAG were tolerated when the duration of infusion was increased. The recommended doses for phase II trials are 700 mg/m2 weekly as a 1-2 hour infusion, 850 mg/m2/24 hours biweekly, and 1500 mg/m2/120 hours biweekly. Therapeutic effects were seen in all schedules and included objective responses in colon carcinoma (one of 13 patients), renal cell carcinoma (one of nine), and Hodgkin's lymphoma (one of two) and objective improvements in esophageal carcinoma (one of three), endometrial carcinoma (two of two), and leiomyosarcoma (one of three).