Prolonged Pharmacokinetic Interaction Between Capecitabine and a CYP2C9 Substrate, Celecoxib.

This study investigated the time course and magnitude of the pharmacokinetic interaction between capecitabine and the cytochrome P450 (CYP) 2C9 substrate celecoxib, with implications for coadministration of fluoropyrimidines with CYP2C9 substrates such as warfarin. Patients received celecoxib 200 mg orally twice daily continuously, with capecitabine (1000 mg/m orally twice daily for 14 days every 21 days) starting 7 days later. Assessment of the drug-drug interaction (DDI) potential was performed using equivalence testing, which assumes that there is no clinically relevant DDI when the calculated 90% confidence intervals (CIs) of the drug exposure ratios fall within the range of 0.

A pharmacodynamic study of sirolimus and metformin in patients with advanced solid tumors.

Background: Sirolimus is a mammalian target of rapamycin (mTOR) inhibitor. Metformin may potentiate mTOR inhibition by sirolimus while mitigating its adverse effects. We conducted a pilot study to test this hypothesis.

Dose-finding and pharmacokinetic study to optimize the dosing of irinotecan according to the UGT1A1 genotype of patients with cancer.

Purpose: The risk of severe neutropenia from treatment with irinotecan is related in part to UGT1A1*28, a variant that reduces the elimination of SN-38, the active metabolite of irinotecan. We aimed to identify the maximum-tolerated dose (MTD) and dose-limiting toxicity (DLT) of irinotecan in patients with advanced solid tumors stratified by the *1/*1, *1/*28, and *28/*28 genotypes.

Patients And Methods: Sixty-eight patients received an intravenous flat dose of irinotecan every 3 weeks.

Evaluation of food effect on pharmacokinetics of vismodegib in advanced solid tumor patients.

Purpose: Vismodegib, an orally bioavailable small-molecule Smoothened inhibitor, is approved for treatment of advanced basal cell carcinoma (BCC). We conducted a pharmacokinetic study of vismodegib in patients with advanced solid tumors to explore the effects of food on drug exposure.

Experimental Design: In part I, patients were randomized to fasting overnight (FO), a high fat meal (HF), or a low fat meal (LF) before a single dose of vismodegib 150 mg.