Abstract 2015: Effect of Early Intensive Statin Therapy on Regression of Coronary Atherosclerosis in Patients with Acute Coronary Syndrome: The Multi-Center Randomized Trial Evaluated by Volumetric Intravascular Ultrasound Comparing Pitavastatin versus Atorvastatin (JAPAN-ACS study)

Abstract

A prior single center study reported that early lipid-lowering therapy with atorvastatin 20 mg/day in patients (pts) with acute coronary syndrome (ACS) significantly reduced coronary plaque volume (PV) of the non-culprit site by intravascular ultrasound (IVUS) evaluation. Effect of statins other than atorvastatin on PV has not been evaluated yet in the setting of ACS. A prospective, randomized open-label parallel group study with blinded endpoint evaluation was perfomed at 33 centers in Japan. Pts with ACS undergoing IVUS-guided percutaneous coronary intervention (PCI) were randomly assigned to receive either 4 mg/day of pitavastatin or 20 mg/day of atorvastatin within 72 hours after PCI. The primary endpoint was the percentage change in non-culprit coronary PV by IVUS from baseline to 8 –12 months follow-up. The study was powered to evaluate non-inferiority of pitavastatin to atorvastatin. Between November 2005 and October 2006, 307 pts (pitavastatin group 153 pts and atorvastatin group 154 pts) were enrolled; 252 pts (82%) had IVUS image qualified for evaluation both at baseline and at follow-up. Low-density lipoprotein cholesterol (LDL-C) decreased from 130.9±33.3mg/dL at baseline to 81.1±23.4mg/dL at 8 –12 months follow-up (p= 0.001) in the pitavastatin group and from 133.8±31.4mg/dL to 84.1±27.4mg/dL (p= 0.001) in the atorvastatin group. PV decreased from 49.8±28.8mm 3 to 41.6±25.0mm 3 (p= 0.001) in the pitavastatin group and from 63.9±33.9mm 3 to 53.3±31.7mm 3 (p= 0.001) in the atorvastatin group. Mean percentage change in PV was −16.9±13.9% and −18.1±14.2% (p=0.5) in the pitavastatin and atorvastatin group, respectively. Upper limit of the 95% confidence interval of the mean difference in percentage change in PV between the two groups (1.11% (−2.27 to 4.48)) did not exceed the pre-defined non-inferiority margin of 5%. There was no significant correlation between percent change in plaque volume and LDL-C at baseline or at follow-up. Early intensive statin therapy with 4mg/day of pitavastatin or 20mg/day of atorvastatin in Japanese patients with ACS resulted in remarkable regression of coronary PV. The effect of pitavastatin 4mg/day on coronary PV was similar to that of atorvastatin 20mg/day.