Cited 32 times since 2005 (1.6 per year) source: EuropePMC Clinical cancer research : an official journal of the American Association for Cancer Research, Volume 11, Issue 4, 1 1 2005, Pages 1504-1511 Phase I pharmacokinetic, food effect, and pharmacogenetic study of oral irinotecan given as semisolid matrix capsules in patients with solid tumors. Soepenberg O, Dumez H, Verweij J, de Jong FA, de Jonge MJ, Thomas J, Eskens FA, van Schaik RH, Selleslach J, Ter Steeg J, Lefebvre P, Assadourian S, Sanderink GJ, Sparreboom A, van Oosterom AT
Purpose
To characterize the maximum-tolerated dose, recommended dose, dose-limiting toxicities (DLT), pharmacokinetic profile, and food effect of orally administered irinotecan formulated as new semisolid matrix capsules.
Experimental design
Irinotecan was given orally in fasted patients once daily for 5 consecutive days and repeated every 3 weeks. Patients were randomly assigned to take the drug along with a high-fat, high-calorie breakfast for the administration at day 1 of the first or second cycle. Dosages tested were 70 and 80 mg/m(2)/day.
Results
Twenty-five patients received 101 cycles of therapy (median two cycles, range 1-15). During the first cycle, grade 3 delayed diarrhea and grade 3 fever were the DLTs at the dosage of 80 mg/m(2)/day in three out of five patients. Hematologic and nonhematologic toxicities were mild to moderate. Exposure to the active metabolite SN-38 was relatively high compared with i.v. infusion, but no relevant accumulation was observed. Food had no significant effect on irinotecan pharmacokinetics. One confirmed partial remission and 10 disease stabilizations were observed in previously treated patients. No association was found between the UGT1A1*28 genotype and the risk of severe irinotecan-induced toxicity.
Conclusions
For oral irinotecan, a dose of 70 mg/m(2)/day for 5 consecutive days every 3 weeks is recommended for further studies. Delayed diarrhea was the main DLT, similar to that observed with intravenously administered irinotecan. This study confirms that oral administration of irinotecan is feasible and may have favorable pharmacokinetic characteristics.
