In patients with mixed dyslipidemia characterized by increased triglycerides (TG), decreased high-density lipoprotein (HDL) cholesterol, and increased low-density lipoprotein (LDL) cholesterol, monotherapy with lipid-altering drugs often fails to achieve all lipid targets. This multicenter, double-blind, active-controlled study evaluated ABT-335 (fenofibric acid) in combination with 2 doses of atorvastatin in patients with mixed dyslipidemia. A total of 613 patients with LDL cholesterol ≥130 mg/dl, TG ≥150 mg/dl, and HDL cholesterol <40 mg/dl for men and <50 mg/dl for women were randomly assigned to ABT-335 (135 mg), atorvastatin (20, 40, or 80 mg), or combination therapy (ABT-335 + atorvastatin 20 or 40 mg) and treated for 12 weeks. Combination therapy with ABT-335 + atorvastatin 20 mg resulted in significantly greater improvements in TG (-45.6% vs -16.5%) and HDL cholesterol (14.0% vs 6.3%) compared with atorvastatin 20 mg and LDL cholesterol (-33.7% vs -3.4%) compared with ABT-335. Similarly, significantly greater improvements were observed with ABT-335 + atorvastatin 40 mg in TG (-42.1% vs -23.2%) and HDL cholesterol (12.6% vs 5.3%) compared with atorvastatin 40 mg and LDL cholesterol (-35.4% vs -3.4%) compared with ABT-335 monotherapy. Combination therapy also improved multiple secondary variables. Combination therapy was generally well tolerated with a safety profile consistent with those of ABT-335 and atorvastatin monotherapies. No rhabdomyolysis was reported. In conclusion, ABT-335 + atorvastatin combination therapy resulted in more effective control of multiple lipid parameters than either monotherapy and may be an appropriate therapy for patients with mixed dyslipidemia.