A phase I trial of SJG-136 (NSC#694501) in advanced solid tumors

SJG-136 is a pyrrolobenzodiazepine dimer that forms DNA crosslinks and has demonstrated broad antitumor activity. We undertook this trial to determine the maximum-tolerated dose (MTD), toxicities and pharmacokinetic (PK) profile of SJG-136 in patients with an advanced solid tumor. In this phase I study, patients were treated with SJG-136 on days 1, 8 and 15 of a 28-day cycle. Dose levels studied were 10, 20, 40 and 60 mu g/m(2). PK parameters of SJG-136 were assessed following the intravenous administration of SJG-136 on days 1 and 15 of cycle 1. Twenty-one patients with advanced solid tumors were treated. Patients had a median of two prior chemotherapy regimens. Fatigue was dose-limiting with SJG-136 60 mu g/m(2)/day administered on days 1, 8 and 15 of a 28-day cycle. Grade 3 thrombocytopenia and delayed onset liver toxicity were seen in one patient each. PK parameters of SJG-136 indicated dose-proportional increases in systemic exposure with increasing doses. No objective responses were seen. For patients with advanced solid tumors, the MTD of SJG-136 is 40 mu g/m(2)/day administered on days 1, 8 and 15 of a 28-day cycle. The major dose limiting toxicity was fatigue. Alternative dosing strategies are now being evaluated.