This was a study of enloplatin in 18 evaluable patients with platinum refractory ovarian cancer. They received an i.v. infusion of enloplatin over 1.5 h without prehydration every 21 days. One patient had a partial response (6%; 95% Cl 0- 26%) lasting 2.8 months. The median survival was 9.4 months (95%; Cl 5.1-19.7%). Neutropenia was the doselimiting toxicity. Nephrotoxicity was manageable. Enloplatin is the major form of the free drug in plasma. However, 13.5 h after initiation of treatment, 85% of the drug in plasma is protein bound. Elimination of the drug is mainly renal. Enloplatin pharmacokinetics is similar to that of carboplatin. Thus, the plasma pharmacokinetics of enloplatin is dictated by the cyclobutanedicarboxylato (CBDCA) ligand and not the novel amino ligand