Pharmacokinetics and pharmacodynamics of fluticasone propionate and salmeterol delivered as a combination dry powder from a capsule-based inhaler and a multidose inhaler in asthma and COPD patients.
BACKGROUND
The object of this study was to assess whether a capsule-based and multidose dry powder inhaler containing salmeterol (as xinafoate salt) 50 μg plus fluticasone propionate (FP) 250 μg [combination (SFC 50/250)] could be equivalent in terms of in vivo drug delivery and systemic exposure.


METHODS
This was a randomized, double-blind, double-dummy, replicate treatment design comparative bioavailability study of SFC 50/250 delivered in a capsule-based inhaler (Rotahaler®) and a multidose dry powder inhaler (Diskus®). Subjects with asthma or chronic obstructive pulmonary (COPD) disease (n=60) were randomized to receive twice-daily SFC 50/250 via a Rotahaler and via Diskus each for two 10-day treatment periods (GlaxoSmithKline Protocol ASR114334).


RESULTS
For FP and salmeterol, the in vitro aerodynamic particle size profiles were within±15% of Diskus for the fine particle mass (FPM) and emitted dose (ED) using the Andersen Cascade Impactor, and ED, mass median aerodynamic diameter, and geometric standard deviation using the New Generation Impactor (NGI). This was also the case for FP but not salmeterol for FPM and fine particle dose using the NGI. For the combined asthma and COPD subjects, the plasma AUC and Cmax for FP and salmeterol were higher for Rotahaler:Rotahaler/Diskus geometric mean ratios (90% confidence intervals) for FP AUC0-τ of 1.52 (1.37-1.67) and Cmax of 1.94 (1.75-2.10) and salmeterol AUC0-τ of 1.15 (1.09-1.21) and Cmax of 1.56 (1.42-1.67). Corresponding values for the primary pharmacodynamic endpoint, weighted mean (0-12 hr) serum cortisol, were 0.928 (0.886-0.971). Inhaled FP/salmeterol via both inhalers was well-tolerated. One serious adverse event, considered possibly related to study medication, resulted in subject withdrawal from the study.


CONCLUSIONS
The in vitro tests and systemic pharmacodynamic endpoints revealed no major differences between the two inhalers, but lacked predictive power and sensitivity to guide in vivo drug delivery performance and systemic exposure. Based on pharmacokinetic endpoints, the inhalers were not considered bioequivalent in terms of systemic exposure. Further studies to refine the Rotahaler performance are ongoing.
1 GlaxoSmithKline , Stockley Park, Uxbridge, UK .
Peter T
PT
Daley-Yates
Rashmi
R
Mehta
Robert H
RH
Chan
Simona X
SX
Despa
Margaret D
MD
Louey
D000280:Administration, Inhalation; D058666:Adrenergic beta-2 Receptor Agonists / Q000008:administration & dosage* / Q000097:blood / Q000493:pharmacokinetics*; D000328:Adult; D000336:Aerosols; D000368:Aged; D000420:Albuterol / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000097:blood / Q000493:pharmacokinetics; D000730:Androstadienes / Q000008:administration & dosage* / Q000097:blood / Q000493:pharmacokinetics*; D019540:Area Under Curve; D001249:Asthma / Q000175:diagnosis / Q000188:drug therapy* / Q000503:physiopathology; D001682:Biological Availability; D001993:Bronchodilator Agents / Q000008:administration & dosage* / Q000097:blood / Q000493:pharmacokinetics*; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D004338:Drug Combinations; D058995:Dry Powder Inhalers; D004867:Equipment Design; D005260:Female; D000068297:Fluticasone-Salmeterol Drug Combination; D006801:Humans; D008168:Lung / Q000187:drug effects* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D009517:New South Wales; D009520:New Zealand; D010316:Particle Size; D011208:Powders; D029424:Pulmonary Disease, Chronic Obstructive / Q000175:diagnosis / Q000188:drug therapy* / Q000503:physiopathology; D016896:Treatment Outcome; D055815:Young Adult
D058666:Adrenergic beta-2 Receptor Agonists; D000336:Aerosols; D000730:Androstadienes; D001993:Bronchodilator Agents; D004338:Drug Combinations; D000068297:Fluticasone-Salmeterol Drug Combination; D011208:Powders; D000420:Albuterol
asthma; chronic obstructive pulmonary disease; dry powder inhaler; fluticasone propionate; pharmacokinetics; salmeterol