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Warfarin pharmacodynamics unaffected by cilomilast
J Kelly1, R D Murdoch, D J Clark
1GlaxoSmithKline, New Frontiers Science Park, Third Ave., Harlow, CM19 5AW Essex, UK. John_A_Kelly@sbphrd.com
The Annals of Pharmacotherapy
|January 17, 2002
Summary
Cilomilast, a phosphodiesterase 4 inhibitor for COPD, does not affect warfarin anticoagulation. This study in healthy volunteers found no significant interaction between the two medications.
Area of Science:
- Pharmacology and Therapeutics
- Drug Interactions
- Respiratory Medicine
Background:
- Chronic obstructive pulmonary disease (COPD) management involves various medications.
- Warfarin is a common anticoagulant requiring careful monitoring.
- Phosphodiesterase 4 (PDE4) inhibitors represent a novel therapeutic class for COPD.
Purpose of the Study:
- To evaluate the potential drug interaction between cilomilast and warfarin.
- To determine if cilomilast affects warfarin's anticoagulant activity.
Main Methods:
- A 28-day, randomized, double-blind, placebo-controlled study.
- 36 healthy male volunteers received warfarin and either cilomilast (15 mg twice daily) or placebo.
- International Normalized Ratio (INR) was measured to assess anticoagulation.
Main Results:
- The mean INR on day 24 was similar between the cilomilast and placebo groups (1.35 vs. 1.38).
- The 90% confidence interval for the INR ratio was within the equivalence range, indicating no significant interaction.
- Adverse events were similar and favorable in both treatment groups.
Conclusions:
- Coadministration of cilomilast does not alter the pharmacodynamics of warfarin.
- Steady-state concentrations of cilomilast do not affect warfarin-induced anticoagulation in healthy volunteers.
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