Fenofibrate is a fibric acid derivative, a prodrug comprising fenofibric acid linked to an isopropyl ester. Fenofibrate is rapidly hydrolyzed after oral ingestion to its pharmacologically active form, fenofibric acid. The effects of fenofibric acid seen in clinical practice have been explained in vivo in transgenic mice and in vitro in human hepatocyte cultures by the activation of peroxisome proliferator activated receptor α (PPARα)
It lowers lipid levels by activating peroxisome proliferator-activated receptor alpha (PPARα). PPARα activates lipoprotein lipase and reduces apoprotein CIII (an inhibitor of lipoprotein lipase activity), which increases lipolysis and elimination of triglyceride-rich particles from plasma. The resulting fall in triglycerides produces an alteration in the size and composition of LDL from small, dense particles (which are thought to be atherogenic due to their susceptibility to oxidation), to large buoyant particles. These larger particles have a greater affinity for cholesterol receptors and are catabolized rapidly
PPARα also increases apoproteins AI and AII, reduces VLDL- and LDL-containing apoprotein B, and increases HDL-containing apoprotein AI and AII. Fenofibrate also reduces serum uric acid levels in hyperuricemic and normal individuals by increasing the urinary excretion of uric acid.