Phase I and Pharmacokinetic Study of YM155, a Small-Molecule Inhibitor of Survivin

Purpose To determine the maximum-tolerated dose (MTD) and assess the safety, pharmacokinetics, and preliminary evidence of antitumor activity of YM155, a small-molecule inhibitor of survivin. Patients and Methods Patients with advanced solid malignancies or lymphoma were treated with escalating doses of YM155 administered by 168-hour continuous intravenous infusion (CIVI). Plasma and urine samples were assayed to determine pharmacokinetic parameters and excretion. Results Forty-one patients received 127 cycles of YM155 at doses ranging from 1.8 to 6.0 mg/m2/d by 168-hour CIVI every 3 weeks. Overall, the most common grade 1 to 2 toxicities were stomatitis, pyrexia, and nausea, whereas grade 3 and 4 toxicities were rare. Reversible elevation in serum creatinine in two patients, with one developing acute tubular necrosis, was dose-limiting at 6.0 mg/m2. The MTD was 4.8 mg/m2. At the MTD, the mean steady-state concentration, clearance, volume of distribution at steady-state, and terminal elimination half-life were 7.7 ng/mL, 47.7 L/h, 1,763 L, and 26 hours, respectively. One complete and two partial responses lasting 8, 24+ and 48+ months occurred in three patients with non-Hodgkin's lymphoma, two patients with hormone- and docetaxel-refractory prostate cancer had prostate-specific antigen responses, and one patient with non–small-cell lung cancer had a minor response. Conclusion YM155 can be administered safely at 4.8 mg/m2/d 168 hours CIVI every 3 weeks. The absence of severe toxicities, attainment of plasma concentrations active in preclinical models, and compelling antitumor activity warrant further disease-directed studies of this agent alone and in combination with chemotherapy in a broad array of tumors.