Pharmacokinetics of teniposide (VM26) after each of three doses were investigated by high-performance liquid chromatographic assay in eight patients with ovarian cancer with normal liver and renal functions. Treatment consisted of a first dose of 100 mg/m2 iv as a 1-hour infusion (Day 1), a second dose of 150 mg/m2 iv as a 1-hour infusion (Day 8), and a third dose of 150 mg/m2 as an approximately 1-day infusion (Day 22). Disappearance of VM26 from plasma followed a biexponential decay pattern. The mean terminal half-life (+/- SE) was 6.9 +/- 0.9 hours after the first dose, 6.1 +/- 0.7 hours after the second dose, and 9.7 +/- 1.4 hours after the third dose. VM26 levels in ascites were lower than those in plasma in the first hours after drug administration, but by 24 hours they were similar or slightly higher. Urinary elimination of VM26 as unchanged drug amounted to less than 10% of the dose.