PARIS and TARRYTOWN, New York, May 26, 2012 /PRNewswire/ -- Sanofi (EURONEXT: SAN and NYSE: SNY) and Regeneron Pharmaceuticals, Inc. (NASDAQ: REGN) today announced additional positive results from a Phase 2 trial of SAR236553/REGN727 (Study 1003, NTC01266876) in patients with heterozygous familial hypercholesterolemia (heFH). SAR236553/REGN727 is a subcutaneously administered, fully-human antibody targeting PCSK9 (proprotein convertase subtilisin/kexin type 9) in clinical development. The results from this study were published online in The Lancet,  and also presented at a late-breaking oral session at the 80 th European Atherosclerosis Society Congress (EAS) in Milan, Italy.  Positive, top-line results from this study were announced in November 2011.  The trial randomized 77 patients with heFH whose LDL-cholesterol (LDL-C) levels remained uncontrolled on statin therapy with or without ezetimibe. Across the four different dosing regimens tested, patients receiving SAR236553/REGN727 for 12 weeks achieved a mean LDL-C reduction from baseline of 28.9% to 67.9%, compared to 10.7% in patients receiving placebo (p<0.05). In addition, in the most intense dose regimen tested where the greatest LDL-C reduction was observed (150 milligrams [mg] every two weeks), 93.8% of patients achieved LDL-C levels lower than 100 mg/dL (2.59 mmol/L), compared to 13.3% of patients on placebo, and 81.3% reached LDL-C levels lower than 70 mg/dL (1.81 mmol/L), compared to none on placebo. There were no serious adverse events (SAE) on active treatment, while a single SAE was recorded for a patient in the placebo group. There were no elevations in liver function tests (LFT) >3 times the upper limit of normal (ULN) and no cases of elevated creatinine kinase (CK) were reported. The most common adverse event reported was injection-site reaction.