Phase I clinical trial of methylene dimethane sulfonate

Methylene dimethane sulfonate is the first member of the homologous series of straight-chain diol sulfonates. It was selected for phase I testing because of high activity in the rat Yoshida sarcoma system and a possible novel site of alkylation due to its small molecular size. Methylene dimethane sulfonate was administered as a rapid iv bolus infusion to 39 patients at doses ranging from 14 to 225 mg/m2. Nausea and vomiting were not severe but total alopecia occurred in the majority of patients at doses greater than 100 mg/m2. The dose-limiting toxic effect was thrombocytopenia, which was cumulative with lower, more prolonged nadirs following successive courses. The median time to platelet count nadir was 21 days, with recovery by 35 days. A minor response was seen in one patient with an adenocarcinoma of the lung. The recommended dose for phase II studies is 125 mg/m2 for patients who have received prior chemotherapy and 150 mg/m2 for those who have not, in an every 35-day schedule.