title: MK-0873, a PDE4 inhibitor, does not influence the pharmacokinetics of theophylline in healthy male volunteers.
abstract: BACKGROUND
  MK-0873 is a novel selective phosphodiesterase-4 inhibitor, which has been in development for the treatment of chronic obstructive pulmonary disease (COPD). In this indication, theophylline is still an important treatment, despite its relatively small therapeutic window. In view of this, it is important to investigate whether MK-0873 could affect the pharmacokinetics, safety and tolerability of theophylline, when both drugs are given concomitantly.
  
  
  OBJECTIVE
  The objective of this study was to investigate the effect of multiple doses of oral MK-0873, a selective phosphodiesterase-4 inhibitor, on the pharmacokinetics, safety and tolerability profile of orally administered theophylline in healthy volunteers.
  
  
  METHODS
  Eight healthy, non-smoking male subjects participated in this randomized, open-label, 2-period, cross-over study. In one period subjects received an oral dose of 2.5mg MK-0873 for 6 days co-administered with a single oral dose of 250 mg theophylline on day 5. The other period consisted of a single dose of 250 mg theophylline on day 1. In each period, blood samples were collected at predefined time points to evaluate theophylline pharmacokinetics.
  
  
  RESULTS
  All subjects completed the study. The study medications were generally well tolerated and no clinically relevant changes were observed in either treatment periods. No significant difference was found in the AUC 0-infinity (77.7 vs. 83.8h ng/ml; p=0.280) and Cmax (6.70 vs. 7.77 ng/ml; p=0.125) of theophylline between the MK-0873+theophylline and theophylline only treatment, and bioequivalence was demonstrated for AUC0-infinity (geometric mean ratio with 90% confidence interval: 0.930 (0.826, 1.047)).
  
  
  CONCLUSIONS
  In this study, in a limited number of subjects, co-administration of oral MK-0873 did not affect the pharmacokinetics, safety, and tolerability of oral theophylline in non-smoking healthy male subjects.
authors.affiliation: Centre for Human Drug Research , Zernikedreef 10, 2333 CL Leiden, The Netherlands. dboot@chdr.nl <dboot@chdr.nl>
authors.forename: J D
authors.initials: JD
authors.lastname: Boot
authors.forename: S L
authors.initials: SL
authors.lastname: De Haas
authors.forename: J M A
authors.initials: JM
authors.lastname: Van Gerven
authors.forename: M
authors.initials: M
authors.lastname: De Smet
authors.forename: T
authors.initials: T
authors.lastname: Leathem
authors.forename: J
authors.initials: J
authors.lastname: Wagner
authors.forename: A
authors.initials: A
authors.lastname: Denker
authors.forename: D
authors.initials: D
authors.lastname: Miller
authors.forename: M B A
authors.initials: MB
authors.lastname: Van Doorn
authors.forename: R C
authors.initials: RC
authors.lastname: Schoemaker
authors.forename: A F
authors.initials: AF
authors.lastname: Cohen
authors.forename: Z
authors.initials: Z
authors.lastname: Diamant
mesh_terms: D000328:Adult; D019540:Area Under Curve; D018592:Cross-Over Studies; D004311:Double-Blind Method; D004347:Drug Interactions; D006801:Humans; D008297:Male; D009287:Naphthyridines / Q000008:administration & dosage / Q000493:pharmacokinetics* / Q000494:pharmacology*; D058988:Phosphodiesterase 4 Inhibitors; D010726:Phosphodiesterase Inhibitors / Q000009:adverse effects / Q000493:pharmacokinetics* / Q000494:pharmacology*; D013806:Theophylline / Q000009:adverse effects / Q000493:pharmacokinetics*; D013810:Therapeutic Equivalency
chemical_list: C532496:MK 0873; D009287:Naphthyridines; D058988:Phosphodiesterase 4 Inhibitors; D010726:Phosphodiesterase Inhibitors; D013806:Theophylline