1. Examination of the effect of increasing doses of etoricoxib on oral methotrexate pharmacokinetics in patients with rheumatoid arthritis.
- Author
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Schwartz JI, Agrawal NG, Wong PH, Miller J, Bachmann K, Marbury T, Hoelscher D, Cavanaugh PF Jr, and Gottesdiener K
- Subjects
- Administration, Oral, Adult, Aged, Antirheumatic Agents administration & dosage, Arthritis, Rheumatoid drug therapy, Cyclooxygenase 2 Inhibitors administration & dosage, Dose-Response Relationship, Drug, Drug Administration Schedule, Drug Interactions, Etoricoxib, Female, Humans, Male, Methotrexate administration & dosage, Middle Aged, Pyridines administration & dosage, Sulfones administration & dosage, Antirheumatic Agents pharmacokinetics, Cyclooxygenase 2 Inhibitors adverse effects, Drug Therapy, Combination adverse effects, Methotrexate pharmacokinetics, Pyridines adverse effects, Sulfones adverse effects
- Abstract
The authors designed 2 randomized controlled studies to examine the effects of etoricoxib 60 to 120 mg daily on methotrexate pharmacokinetics in 50 rheumatoid arthritis (RA) patients on stable doses of methotrexate (7.5-20 mg). Patients received oral methotrexate at baseline and on days 7 and 14. In study 1, patients received etoricoxib 60 mg (days 1-7) and then 120 mg (days 8-14); in study 2, patients received etoricoxib 90 mg (days 1-7) and then 120 mg (days 8-14). For study 1, the AUC(0-infinity) geometric mean ratio (GMR) (90% confidence interval [CI]) for day 7 versus baseline was 1.01 (0.91, 1.12) for etoricoxib 60 mg; the area under the plasma concentration-time curve from zero to infinity (AUC(0-infinity)) GMR (90% CI) for day 14 was 1.28 (1.15, 1.42) for etoricoxib 120 mg. For study 2, the AUC(0-infinity) GMR (90% CI) for day 7 versus baseline was 1.07 (1.01, 1.13) for etoricoxib 90 mg; the AUC(0-infinity) GMR (90% CI) for day 14 was 1.05 (0.99, 1.11) for etoricoxib 120 mg. In summary, etoricoxib 60 and 90 mg had no effect on methotrexate plasma concentrations. Although no effect on methotrexate pharmacokinetics was observed with etoricoxib 120 mg in study 2, GMR AUC(0-infinity) fell outside the prespecified bounds in study 1. Standard monitoring of methotrexate-related toxicity should be continued when etoricoxib and methotrexate are administered concurrently, especially with doses >90 mg etoricoxib.
- Published
- 2009
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