ABSTRACT
OBJECTIVE: To evaluate the pharmacokinetic inter-patient variability of 30-min hyperthermic intraperitoneal oxaliplatin chemotherapy. PATIENTS AND METHODS: Data were obtained from 24 patients who were treated according to two procedures of heated intra-operative intraperitoneal oxaliplatin. For the first procedure (12 patients), the solution instilled within the peritoneal cavity contained oxaliplatin, and a delay of 8-10 min was necessary to reach a temperature of 42-43 degrees C. For the second procedure (12 patients), the cavity was initially filled only with the dextrose solution, and oxaliplatin was added to the peritoneal instillate when temperature reached 42-43 degrees C. Plasma and peritoneal fluid oxaliplatin concentrations were analyzed according to a population pharmacokinetic approach using NONMEM. RESULTS: Peritoneal and total plasma data were simultaneously analyzed according to a three-compartment pharmacokinetic model. The peritoneal half-life ranged between 18 and 42 min. The mean peritoneal clearance was 5.47 L/h (+/-21%), and the mean plasma clearance was 3.71 L/h (+/-47%). The heated intra-operative procedure did not have any impact on oxaliplatin pharmacokinetics. CONCLUSION: The inter-individual variability was larger for plasma pharmacokinetic parameters than that for peritoneal parameters. However, the percentage of oxaliplatin dose absorbed during a 30-min hyperthermic intraperitoneal chemotherapy may vary from 40 to 68%. The present pharmacokinetic model will be useful to implement pharmacokinetic evaluation of further clinical trials of hyperthermic intraperitoneal chemotherapy based on platinum compounds' administration.
Subject(s)
Antineoplastic Agents/pharmacokinetics , Hyperthermia, Induced , Neoplasms/metabolism , Organoplatinum Compounds/pharmacokinetics , Pyridines/pharmacokinetics , Adult , Aged , Antineoplastic Agents/administration & dosage , Antineoplastic Agents/adverse effects , Ascitic Fluid/chemistry , Chromatography, High Pressure Liquid , Combined Modality Therapy , Dose-Response Relationship, Drug , Drug Monitoring , Female , Humans , Infusions, Parenteral , Male , Middle Aged , Neoplasms/drug therapy , Organoplatinum Compounds/administration & dosage , Organoplatinum Compounds/adverse effects , Pyridines/administration & dosage , Pyridines/adverse effectsABSTRACT
Carboplatin is an alternative for cisplatin in the treatment of urothelial cancers. A pharmacologically guided phase I study of carboplatin in combination with methotrexate (30 mg/m2) and vinblastine (4 mg/m2) was conducted in ten patients by increment of the area under the plasma concentration versus time curve (AUC) for ultrafilterable carboplatin using the Calvert formula. The maximal tolerated AUC was 5 mg ml-1 min, with neutropenia being the dose-limiting toxicity. There was a significant linear correlation between the percentage of decrease in neutrophil count and the carboplatin AUC. Determination of the glomerular filtration rate by the isotopic method allowed us to adapt the dose of carboplatin given to patients suffering from urothelial cancer, who frequently have impaired renal function. The recommended AUC for phase II study is 4 mg ml-1 min.