Study design, rationale, and baseline characteristics: evaluation of fenofibric acid on carotid intima-media thickness in patients with type IIb dyslipidemia with residual risk in addition to atorvastatin therapy (FIRST) trial.

Purpose: Elevated triglycerides (TG) and low high-density lipoprotein cholesterol (HDL-C) levels contribute to cardiovascular disease risk and can be effectively treated with fenofibric acid. A trial is under way to evaluate the effect of once-daily fenofibric acid or placebo on carotid intima-media thickness (CIMT) progression in patients with controlled low-density lipoprotein cholesterol (LDL-C) levels achieved through atorvastatin treatment, but with high TG and low HDL-C levels.

Methods: In this multicenter, double-blind study, 682 patients were randomized to once-daily delayed-release capsules of choline fenofibrate 135 mg (fenofibric acid [Trilipix(®); Abbott, North Chicago, IL]) or placebo plus atorvastatin treatment after a 2- to 10-week diet and atorvastatin run-in period. Key inclusion criteria included age ≥45 years; posterior-wall common CIMT ≥0.7 mm on at least one side at baseline; fasting results of TG ≥150 mg/dL, and HDL-C ≤45 mg/dL for men or HDL-C ≤55 mg/dL for women at screening while receiving atorvastatin; controlled LDL-C; and known coronary heart disease (CHD) or a CHD risk equivalent. The primary efficacy variable is the rate of change from baseline through week 104 in the mean posterior-wall intima-media thickness of the common carotid arteries (composite value of left and right sides).

Conclusions: This trial is the first to examine the effect of fenofibric acid on CIMT and the first CIMT trial to select patients with controlled LDL-C and elevated TG and low HDL-C as inclusion criteria. Also, this trial will prospectively evaluate the effect of treatment on LDL particles and address shortcomings of previous CIMT trials.