Pharmacodynamic interaction between ezetimibe and rosuvastatin.
BACKGROUND
Ezetimibe is a lipid-lowering drug indicated for the treatment of hypercholesterolemia as co-administration with HMG-CoA reductase inhibitors (statins) or as monotherapy. The primary objectives of this study were to evaluate the pharmacodynamic effects and safety of the co-administration of ezetimibe and the new statin rosuvastatin. A secondary objective was to examine the potential for a pharmacokinetic interaction between ezetimibe and rosuvastatin.


METHODS
This was a randomized, evaluator (single)-blind, placebo-controlled, parallel-group study in healthy hypercholesterolemic subjects (untreated low-density lipoprotein cholesterol [LDL-C] > or = 130 mg/dL [3.37 mmol/L]). After the outpatient screening and NCEP Step I diet stabilization periods, 40 subjects were randomized to one of the 4 following treatments: rosuvastatin 10 mg plus ezetimibe 10 mg (n = 12); rosuvastatin 10 mg plus placebo (matching ezetimibe 10 mg) (n = 12); ezetimibe 10 mg plus placebo (matching ezetimibe 10 mg) (n = 8); or placebo (2 tablets, matching ezetimibe 10 mg) (n = 8). All study treatments were administered once daily in the morning for 14 days as part of a 16-day inpatient confinement period. Fasting serum lipids were assessed pre-dose on days 1 (baseline), 7, and 14 by direct quantitative assay methods. Safety was evaluated by monitoring laboratory tests and recording adverse events. Blood samples were collected for ezetimibe and rosuvastatin pharmacokinetic evaluation prior to the first and last dose and at frequent intervals after the last dose (day 14) of study treatment. Plasma ezetimibe, total ezetimibe (ezetimibe plus ezetimibe-glucuronide) and rosuvastatin concentrations were determined by validated liquid chromatography with tandem mass spectrometric detection (LC-MS/MS) assay methods.


RESULTS
All active treatments caused statistically significant (p < or = 0.02) decreases in LDL-C concentration versus placebo from baseline to day 14. The co-administration of ezetimibe and rosuvastatin caused a significantly (p < 0.01) greater reduction in LDL-C and total cholesterol than either drug alone. In this 2-week inpatient study with restricted physical activity there was no apparent effect of any treatment on high-density lipoprotein cholesterol (HDL-C) or triglycerides. The co-administration of ezetimibe and rosuvastatin caused a significantly (p < 0.01) greater percentage reduction in mean LDL-C (-61.4%) than rosuvastatin alone (-44.9%), with a mean incremental reduction of -16.4% (95%CI -26.3 to -6.53). Reported side effects were generally mild, nonspecific, and similar among treatment groups. There were no significant increases or changes in clinical laboratory tests, particularly those assessing muscle and liver function. There was no significant pharmacokinetic drug interaction between ezetimibe and rosuvastatin.


CONCLUSIONS
Co-administration of ezetimibe 10 mg with rosuvastatin 10 mg daily caused a significant incremental reduction in LDL-C compared with rosuvastatin alone. Moreover, co-administering ezetimibe and rosuvastatin was well tolerated in patients with hypercholesterolemia.
Kosoglou
Teddy
T
Department of Early Clinical Research & Experimental Medicine, Schering-Plough Research Institute, Kenilworth, NJ 07033, USA. teddy.kosoglou@spcorp.com
Statkevich
Paul
P
Yang
Bo
B
Suresh
Ramachandran
R
Zhu
Yali
Y
Boutros
Tanya
T
Maxwell
Stephen E
SE
Tiessen
Renger
R
Cutler
David L
DL
D000328:Adult; D000924:Anticholesteremic Agents / Q000493:pharmacokinetics* / Q000627:therapeutic use; D001384:Azetidines / Q000493:pharmacokinetics* / Q000627:therapeutic use; D004357:Drug Synergism; D004359:Drug Therapy, Combination; D000069438:Ezetimibe; D005260:Female; D005464:Fluorobenzenes / Q000493:pharmacokinetics* / Q000627:therapeutic use; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000493:pharmacokinetics / Q000627:therapeutic use; D006937:Hypercholesterolemia / Q000097:blood / Q000188:drug therapy*; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D011743:Pyrimidines / Q000493:pharmacokinetics* / Q000627:therapeutic use; D000068718:Rosuvastatin Calcium; D016037:Single-Blind Method; D013449:Sulfonamides / Q000493:pharmacokinetics* / Q000627:therapeutic use; D016896:Treatment Outcome
D000924:Anticholesteremic Agents; D001384:Azetidines; D005464:Fluorobenzenes; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; D011743:Pyrimidines; D013449:Sulfonamides; D000068718:Rosuvastatin Calcium; D000069438:Ezetimibe