NEW YORK (Reuters Health) – Patients with hypercholesterolemia who do not reach target lipid levels with rosuvastatin have a better change of reaching their goals by adding ezetimibe as opposed to doubling the statin dose, a new study indicates.

The study was reported May 20 in the American Journal of Cardiology, to coincide with presentation at the National Lipid Association meeting in New York City. It joins several other studies that have found similar results, Dr. Harold E. Bays of the Louisville Metabolic and Atherosclerosis Research Center in Louisville, Kentucky and colleagues note.

“While not especially surprising, it was reassuring that the addition of another lipid-altering drug (ezetimibe) with a complimentary mechanism of action to a statin (rosuvastatin) was able to achieve multiple favorable lipid effects,” Dr. Bays told Reuters Health by e-mail.

The study included 440 hypercholesterolemic adults at moderately high or high risk for heart disease. Their mean age was 61 years.

After a 4-week run-in with rosuvastatin 5 or 10 mg/day, subjects not at their LDL target (< 100 mg/dL for moderately high/high-risk subjects without atherosclerotic vascular disease or < 70 mg/dL for those with atherosclerotic vascular disease) either added ezetimibe 10 mg/day or upped the rosuvastatin dose from 5 to 10 mg/day or from 10 to 20 mg/day.

Adverse events were “generally low” and not different between groups.

Pooled data showed that adding ezetimibe to rosuvastatin reduced LDL cholesterol by 21%, whereas doubling the rosuvastatin dose reduced LDL by only 5.7% – a significant between-group difference of 15.2% (P < 0.001).

The 21% reduction in LDL from baseline with add-on ezetimibe is similar in magnitude to that seen in trials of other statins, the authors note. The roughly 6% reduction in LDL with up-titration of rosuvastatin is also similar in magnitude to other statin up-titration trials.

Individual data showed that ezetimibe plus rosuvastatin 5 mg reduced LDL cholesterol to a far greater degree than rosuvastatin 10 mg (12.3% difference, P < 0.001). Likewise, ezetimibe plus rosuvastatin 10 mg reduced LDL cholesterol more than did rosuvastatin 20 mg (17.5% difference, P < 0.001).

Compared with doubling the rosuvastatin dose, ezetimibe add-on achieved “significantly greater attainment” of LDL target levels < 70 mg/dL or < 100 mg/dL (59.4% vs 30.9%, P < 0.001) and < 70 mg/dL in all subjects (43.8% vs 17.5%; P < 0.001), the investigators report.

Add-on ezetimibe also produced significantly greater reductions in total cholesterol, non-HDL-cholesterol and apolipoprotein B (P < 0.001) and resulted in similar effects on other lipid parameters.

This study, the authors say, demonstrates the “comparative safety and efficacy” of ezetimibe added to rosuvastatin versus rosuvastatin up-titration. “Adding ezetimibe to common starting doses of rosuvastatin (5 or 10 mg) may better allow patients to achieve treatment goals,” Dr. Bays said.

He and his colleagues caution, however, that the duration of the study was relatively short (6 weeks) and the population was mostly white (77%) and male (62%). This limits the ability to generalize the findings to longer term therapy or other ethnically diverse populations.

The study was funded by Merck/Schering Plough Pharmaceuticals.

Am J Cardiol 2011.