Ascending Multi-dose Study of REGN727(SAR236553) With and Without Concomitant Atorvastatin

This study will test the safety, tolerability, and bioeffects (how the body reacts to the drug) of REGN727 compared with placebo (an inactive substance that contains no medicine) in hyperlipidemic patients with or without atorvastatin therapy. The study drug and placebo will be administered by subcutaneous injection at the clinic. There will be a total of 2 or 3 study drug injections over 16 clinic visits, which will include 3 overnight stays(study duration 148 days, not including the screening period). Patients on atorvastatin will take their daily dose in the morning for the duration of the study. Patients will be monitored by the study staff for side effects and the body's response to the study drug. Vital signs(blood pressure, temperature, breathing and heart rate) will be checked, and blood and urine samples will be collected at some or all visits.