Coadministration of Therapies Is OK

A study of 2 cholesterol-lowering therapies found that no major drug-drug interactionsoccurred when WelChol (colesevelam HCl) was coadministered with Tri-Cor (fenofibrate tablets). WelChol is a bile acid sequestrant and TriCor is a fibrate.

The study was an open-label, 3-way crossover drug interaction study thatinvolved 30 healthy participants between the ages of 19 and 50 years. During thestudy, each participant randomly received 3 different treatment regimens, consistingof WelChol (6 tablets at 625 mg) and TriCor (1 tablet at 160 mg), over 27 days.The regimens included (1) WelChol and TriCor coadministered with a standardlow-fat breakfast; (2) TriCor with a standard low-fat breakfast, followed by Wel-Chol 4 hours later with a standard low-fat lunch; and (3) TriCor alone with a standardlow-fat breakfast. Each treatment regimen was separated by a 10-daywashout period. Following each dosing, blood levels of fenofibric acid (the activemetabolite of TriCor) were followed for 120 hours.

The results indicated that WelChol had no significant effect on the bioavailabilityof TriCor when TriCor was administered 4 hours prior to WelChol. Also, whenboth drugs were given together, WelChol had no major effect on the total drugexposure of fenofibric acid. (The findings were reported in Clinical Pharmacokinetics,September 2004.)