Although dual low-density lipoprotein cholesterol (LDL-C)-lowering therapy (DLLT) with statin-ezetimibe combination showed clinical benefit in patients with acute coronary syndrome (ACS) confirming “the lower, the better,” the underlying mechanisms of DLLT are still unknown.PRECISE-IVUS trial evaluated the effects of DLLT on IVUS-derived coronary atherosclerosis and lipid profile, compared with atorvastatin monotherapy, quantifying the coronary plaque response in 100 ACS patients. We explored the potential predictors of plaque regression.Lower total cholesterol, LDL-C, triglyceride, remnant-like particles cholesterol, and stronger reduction of small dense LDL-C and cholesterol absorption markers were observed in patients with plaque regression compared to those with progression. Multivariate analysis revealed that achieved LDL-C was the strongest predictor for coronary plaque regression (95% CI: 0.944–1.000, p = 0.05), followed by age (95% CI: 0.994–1.096, p = 0.09).Incremental LDL-C lowering by DLLT was associated with stronger coronary plaque regression, reconfirming that lowering LDL-C to levels below previous targets provided additional clinical benefit.