title: Pharmacokinetic properties and bioequivalence of orally inhaled salbutamol in healthy Chinese volunteers.
abstract: BACKGROUND
  Salbutamol is a short-acting β2-adrenergic receptor agonist that has been used for many years for relief of bronchospasm. However, studies on the pharmacokinetic profile of orally inhaled salbutamol doses used in clinical practice have not yet been reported in Chinese subjects.
  
  
  OBJECTIVE
  The aim of this study was to compare the pharmacokinetics and evaluate the bioequivalence of two orally inhaled salbutamol formulations.
  
  
  METHODS
  A single-dose randomized fasting two-period, two-treatment and two-sequence crossover open-label bioequivalence study was conducted in 24 healthy Chinese adult male volunteers, with a 1-week washout period between treatments. Plasma concentrations of salbutamol were determined using liquid chromatography coupled to tandem mass spectrometry. Pharmacokinetic parameters, including AUC0-0.33 h, AUC0-24 h and Cmax were calculated and the 90% confidence intervals of the ratio (test/reference) pharmacokinetic parameters were obtained by analysis of variance on logarithmically transformed data.
  
  
  RESULTS
  The mean (SD) pharmacokinetic parameters of the reference drug were AUC0-0.33 h, 227.2 (89.9) pg·h/ml; AUC0-24 h, 2551.9 (1008.0) pg·h/ml; Cmax, 801.3 (307.3) pg/ml and t1/2, 5.14(1.36) h. Those of the test drug were AUC0-0.33 h, 244.0 (104.4) pg·h/ml; AUC0-24 h, 2664.4 (1081.8) pg·h/ml; Cmax, 873.7 (374.4) pg/ml, t1/2, 5.29 (1.23) h. The median value for Tmax was 0.25 h for both formulations. The 90% confidence intervals for the AUC0-0.33 h, AUC0-24 h and Cmax were in the range of 0.892-1.208, 0.876-1.195 and 0.911-1.203, respectively.
  
  
  CONCLUSIONS
  This single-dose study found that the test and reference products met the regulatory criteria for bioequivalence of China in healthy Chinese volunteers.
authors: a Center of Clinical Pharmacology, 2nd Affiliated Hospital, School of Medicine, Zhejiang University , Hangzhou , China ;
authors: Bo
authors: B
authors: Jiang
authors: a Center of Clinical Pharmacology, 2nd Affiliated Hospital, School of Medicine, Zhejiang University , Hangzhou , China ;
authors: Zourong
authors: Z
authors: Ruan
authors: a Center of Clinical Pharmacology, 2nd Affiliated Hospital, School of Medicine, Zhejiang University , Hangzhou , China ;
authors: Jinliang
authors: J
authors: Chen
authors: a Center of Clinical Pharmacology, 2nd Affiliated Hospital, School of Medicine, Zhejiang University , Hangzhou , China ;
authors: Honggang
authors: H
authors: Lou
authors: a Center of Clinical Pharmacology, 2nd Affiliated Hospital, School of Medicine, Zhejiang University , Hangzhou , China ;
authors: Rong
authors: R
authors: Shao
authors: b Shanghai Fronthealth Pharmaceutical Technology Co, Ltd , Shanghai , China.
authors: Fang
authors: F
authors: Jin
authors: a Center of Clinical Pharmacology, 2nd Affiliated Hospital, School of Medicine, Zhejiang University , Hangzhou , China ;
authors: Huahao
authors: H
authors: Shen
mesh_terms: D000280:Administration, Inhalation; D000284:Administration, Oral; D000328:Adult; D000420:Albuterol / Q000493:pharmacokinetics*; D019540:Area Under Curve; D044466:Asian People; D002626:Chemistry, Pharmaceutical / Q000379:methods; D018592:Cross-Over Studies; D005215:Fasting; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D013810:Therapeutic Equivalency; D055815:Young Adult
chemical_list: D000420:Albuterol
keywords: inhalation administration; lung deposition; particle size profile; systemic absorption; β2-adrenergic receptor