Pharmocokinetics of an etoposide infused over three days: Concomitant infusion with cisplatin

The pharmacokinetics of a 72-hours infusion of 240 mg/m² etoposide administered concurrently with 90 mg/m² cisplatin was studied in 12 lung cancer patients. The area under the curve (AUC), elimination half-life, steady state concentration, systemic clearance, renal clearance of etoposide and distribution volume at steady state were 225.4±39.2 μg×h/ml, 8.1±3.4 h, 3.1±0.6 μg/ml, 18.8±3.1 ml/min/m², 9.6±3.8 l/m², respectively, whcih were in accordance with those reported previously in patients treated wih etoposide alone. Although concentration at 24 hours, total bilirubin level and total protein level were correlated with the AUC which in trurn correlated with hematologic toxicity, the variables were not predictive of hematologic toxicity. We conclude that the concomitant administration of cisplatin at a dose level of 30 mg/m²/day might not affect the pharmacokinetics of prolonged etoposide infusion