Phase II study of porfiromycin vs mitomycin‐c utilizing acute intermittent schedules

Abstract

A randomized prospective study of Mitomycin‐C and its N‐methyl derivative, Porfiromycin, was conducted. Thirty‐two patients with disseminated gastrointestinal cancer or other disseminated abdominal adenocarcinoma were treated with Mitomycin‐C 31 patients received Porfiromycin. Both drugs were given by acute intermittent bolus schedule (Mitomycin‐C, 22.5 mg/M² or Porfiromycin, 75 mg/M² every 6–8 weeks as a single bolus i.v. injection). Eleven patients (34%) who received Mitomycin‐C entered into partial remission. In 10 of the 31 patients (32%) receiving Porfiromycin, partial remission occurred. Analysis by tumor type demonstrated that in the Mitomycin‐C‐treated group responses occurred in 4 of 12 patients with colorectal carcinoma, in 4 of 9 with upper GI cancers, and in 3 of 11 with ovarian cancer. Correspondingly in the Porfiromycin group responses occurred in 2 of 12 colorectal carcinoma patients, in 3 of 7 upper GI cancer patients, and in 5 of 12 ovarian cancer patients. Both drugs produced significant myelosuppression; however, Porfiromycin toxicity appeared more cumulative. Further clinical trial of Mitomycin in an acute intermittent bolus schedule appears justified.