One hundred and nine patients with advanced malignancy, refractory to conventional therapy, were treated with a weekly schedule of methyl-GAG. Ninety-one patients (83%) were less than fully ambulatory. Sixty-five patients were fully evaluable for response. There were two complete and nine partial responses. An additional nine patients had objective tumor regressions and were classified as improved. The median duration of response was 5 months. Toxic effects were primarily mucositis (17 patients) and nausea and vomiting (14 patients). Sixty-seven patients had no manifestations of drug toxicity. Responses observed in a wide variety of solid tumors warrant further clinical trials.