Phase II evaluation of bryostatin-1 in metastatic melanoma

In this phase II study we assessed the efficacy of bryostatin-1 (NSC 339555 ) in metastatic melanoma patients when given intravenously either once a we ek at a dose of 25 mug/ m(2) per day over 24 h for 3 weeks or at 40 mug/m(2 ) per day over 72 h every 2 weeks. Treatment courses were repeated every 4 weeks. Patients who had received one prior chemotherapy regimen for advance d melanoma, with or without biotherapy, were randomized to one or the other bryostatin-1 dose schedules until 12 patients were registered to each arm. Because there was one confirmed response among the 12 patients who receive d the 72 h dose schedule, 25 more patients were added to that arm. No proph ylactic medications were given. Objective tumour measurements were used to assess the efficacy of the regimen. The National Cancer Institutes common t oxicity criteria were used to grade reactions. In total, 49 patients with m etastatic melanoma, none having symptomatic brain metastasis, were studied. Of these, 12 patients received the 24 h bryostatin-1 regimen, while the re maining 37 received the 72 h regimen. One patient receiving the 72 h regime n had a partial response lasting over 7 months. Muscle pain occurred in ove r 90% of the patients and was the dose-limiting side effect of the 72 h reg imen. Grade 3/4 nausea and vomiting were more common on the 24 h regimen th an on the 72 h one (35% versus 5% of patients). There was no therapy-relate d thrombocytopenia. Neutropenia was mild and mainly limited to patients rec eiving the 72 h regimen. Bryostatin-1 has limited activity against melanoma when given by 72 h Intravenous infusion. (C) 2001 Lippincott Williams & Wi lkins.