A study of 2 cholesterol-lowering therapies found that no major drug-drug interactions occurred 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 that involved 30 healthy participants between the ages of 19 and 50 years. During the study, each participant randomly received 3 different treatment regimens, consisting of 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 standard low-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 standard low-fat breakfast. Each treatment regimen was separated by a 10-day washout period. Following each dosing, blood levels of fenofibric acid (the active metabolite of TriCor) were followed for 120 hours.
The results indicated that WelChol had no significant effect on the bioavailability of TriCor when TriCor was administered 4 hours prior to WelChol. Also, when both drugs were given together, WelChol had no major effect on the total drug exposure of fenofibric acid. (The findings were reported in Clinical Pharmacokinetics, September 2004.)