IPSIndian Journal of Pharmacology
Home  IPS  Feedback Subscribe Top cited articles Login 
Users Online : 1363 
Small font sizeDefault font sizeIncrease font size
Navigate Here
 »   Next article
 »   Previous article
 »   Table of Contents

Resource Links
 »   Similar in PUBMED
 »  Search Pubmed for
 »  Search in Google Scholar for
 »Related articles
 »   Citation Manager
 »   Access Statistics
 »   Reader Comments
 »   Email Alert *
 »   Add to My List *
 * Requires registration (Free)
 

 Article Access Statistics
    Viewed9189    
    Printed318    
    Emailed20    
    PDF Downloaded448    
    Comments [Add]    
    Cited by others 5    

Recommend this journal

 

 RESEARCH PAPER
Year : 2004  |  Volume : 36  |  Issue : 1  |  Page : 29-33

Comparative bioavailability of three oral formulations of sustained release theophylline in healthy human subjects


1 Department of Pharmaceutical Medicine, Faculty of Pharmacy, Jamia Hamdard, Hamdard University, New Delhi - 110062, India
2 Department of Clinical Pharmacology and Pharmacokinetics, Ranbaxy Research Laboratories, Gurgaon - 122001, India

Correspondence Address:
P L Sharma
Department of Clinical Pharmacology and Pharmacokinetics, Ranbaxy Research Laboratories, Gurgaon - 122001
India
Login to access the Email id

Source of Support: None, Conflict of Interest: None


Rights and PermissionsRights and Permissions

Objective: To determine the bioequivalence of two marketed test formulations (A, B) as compared to a reference formulation (R) of slow release theophylline in healthy volunteers. Material and Methods: The study was conducted as an open label, balanced, randomized, three-treatment, three-period, three-sequence single-dose crossover study to determine the bioequivalence of Phylobid 200 mg SR tablets (A) and Theobid 200 mg SR tablets (B) as compared to Theostan CR 200 mg capsule (R) under fasting conditions. A group of 12 healthy, adult, male human subjects participated in this study. The bioavailability was compared using pharmacokinetic parameters Cmax, Tmax, AUC0-t, and AUC0-¥. Moreover, the 90% confidence interval (CI) for the ratio of logarithmic transformed Cmax, AUC0-t and AUC0-¥ was also used to determine bioequivalence. A washout period of seven days was kept between each study period. Serial blood samples were collected at 0, 0.5, 2, 3, 4, 6, 8, 10, 12, 15, 18, 21 and 24 h during each study. Results: The 90% CI for the log transformed data forCmax, AUC0-t, and AUC0-¥ for both the test products fell outside the prescribed limits of bioequivalence for narrow therapeutic index drugs i.e. 90-111%. The T/R (test/reference) ratio of product A was quite close to the prescribed limits of bioequivalence (95-105%), while for product B the T/R ratio was not satisfactory. Conclusions: None of the test products of theophylline were bioequivalent to the reference product. The finding is of special significance since substitution of one brand of theophylline, a drug with a narrow therapeutic index, with another brand may result in sub-therapeutic response in patients.






[FULL TEXT] [PDF]*


        
Print this article     Email this article

Site Map | Home | Contact Us | Feedback | Copyright and Disclaimer
Online since 20th July '04
Published by Wolters Kluwer - Medknow