Oxaliplatin pharmacokinetics and pharmacodynamics in adult cancer patients with impaired renal function.

PURPOSE

To characterize the pharmacokinetics and pharmacodynamics of oxaliplatin in cancer patients with impaired renal function.

EXPERIMENTAL DESIGN

Thirty-four patients were stratified by 24-h urinary creatinine clearance (CrCL) into four renal dysfunction groups: group A (control, CrCL, >or=60 mL/min), B (mild, CrCL, 40-59 mL/min), C (moderate, CrCL, 20-39 mL/min), and D (severe, CrCL, <20 mL/min). Patients were treated with 60 to 130 mg/m2 oxaliplatin infused over 2 h every 3 weeks. Pharmacokinetic monitoring of platinum in plasma, plasma ultrafiltrates, and urine was done during cycles 1 and 2.

RESULTS

Plasma ultrafiltrate platinum clearance strongly correlated with CrCL (r2 = 0.712). Platinum elimination from plasma was triphasic, and maximal platinum concentrations (Cmax) were consistent across all renal impairment groups. However, only the beta-half-life was significantly prolonged by renal impairment, with values of 14.0 +/- 4.3, 20.3 +/- 17.7, 29.2 +/- 29.6, and 68.1 h in groups A, B, C, and D, respectively (P = 0.002). At a dose level of 130 mg/m2, the area under the concentration time curve increased in with the degree of renal impairment, with values of 16.4 +/- 5.03, 39.7 +/- 11.5, and 44.6 +/- 14.6 mug.h/mL, in groups A, B, and C, respectively. However, there was no increase in pharmacodynamic drug-related toxicities. Estimated CrCL using the Cockcroft-Gault method approximated the measured 24-h urinary CrCL (mean prediction error, -5.0 mL/min).

CONCLUSIONS

Oxaliplatin pharmacokinetics are altered in patients with renal impairment, but a corresponding increase in oxaliplatin-related toxicities is not observed.