title: The effect of erythromycin on the pharmacokinetics of rosuvastatin.
abstract: OBJECTIVE
  To examine in vivo the effect of erythromycin on the pharmacokinetics of rosuvastatin [an inhibitor of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase]. Erythromycin is a potent inhibitor of CYP3A4 that markedly increases circulating levels of some other HMG-CoA reductase inhibitors.
  
  
  METHODS
  In this randomised, double-blind, two-way cross-over, placebo-controlled trial 14 healthy volunteers were given 500 mg erythromycin or placebo four times daily for 7 days. A single dose of 80 mg rosuvastatin was co-administered on day 4 of dosing. Plasma concentrations of rosuvastatin and active and total HMG-CoA reductase inhibitors were measured up to 96 h after dosing.
  
  
  RESULTS
  Eleven volunteers had data available from both dosing periods. There was no increase in rosuvastatin plasma exposure following co-administration with erythromycin compared to placebo. In fact, following co-administration with erythromycin, rosuvastatin geometric least square mean AUC((0-t)) and C(max) were 20% and 31%, respectively, lower than with placebo. Individual treatment ratios for AUC((0-t)) ranged from 0.48 to 1.17, and for C(max) ranged from 0.33 to 2.19. Essentially all of the circulating active HMG-CoA reductase inhibitors and most (>94%) of the total inhibitors were accounted for by rosuvastatin. Erythromycin did not affect the proportion of circulating active or total inhibitors accounted for by circulating rosuvastatin.
  
  
  CONCLUSIONS
  Erythromycin did not produce any increase in rosuvastatin plasma exposure. This indicates that CYP3A4 metabolism is not an important clearance mechanism for rosuvastatin, a result consistent with previous findings. The small decreases in rosuvastatin AUC((0-t)) and C(max) that occurred as a consequence of short-term treatment with erythromycin are unlikely to have relevance to long-term treatment with rosuvastatin.
authors.affiliation: AstraZeneca, Alderley Park, Mereside, Macclesfield, Cheshire, SK10 4TG, UK.
authors.forename: K J
authors.initials: KJ
authors.lastname: Cooper
authors.forename: P D
authors.initials: PD
authors.lastname: Martin
authors.forename: A L
authors.initials: AL
authors.lastname: Dane
authors.forename: M J
authors.initials: MJ
authors.lastname: Warwick
authors.forename: A
authors.initials: A
authors.lastname: Raza
authors.forename: D W
authors.initials: DW
authors.lastname: Schneck
mesh_terms: D000328:Adult; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D019540:Area Under Curve; D018592:Cross-Over Studies; D051544:Cytochrome P-450 CYP3A; D065607:Cytochrome P-450 Enzyme Inhibitors; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism; D004311:Double-Blind Method; D004347:Drug Interactions; D004917:Erythromycin / Q000494:pharmacology*; D005464:Fluorobenzenes / Q000493:pharmacokinetics*; D006207:Half-Life; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000493:pharmacokinetics*; D008297:Male; D008657:Metabolic Clearance Rate; D011743:Pyrimidines; D000068718:Rosuvastatin Calcium; D013449:Sulfonamides
chemical_list: D000900:Anti-Bacterial Agents; D065607:Cytochrome P-450 Enzyme Inhibitors; D005464:Fluorobenzenes; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; D011743:Pyrimidines; D013449:Sulfonamides; D004917:Erythromycin; D000068718:Rosuvastatin Calcium; D003577:Cytochrome P-450 Enzyme System; C104464:CYP3A protein, human; D051544:Cytochrome P-450 CYP3A; C510163:CYP3A4 protein, human