Comparative bioavailability of two dexamethasone tablet formulations in Indonesian healthy volunteers.
OBJECTIVE
To compare the bioavailability of two dexamethasone (CAS 50-02-2) tablet formulations -- 4 mg Dexmethsone tablets as test formulation and 4 mg tablets of the originator product as reference formulation.


METHODS
The study was conducted according to an open-label, randomized two-way crossover design with a one-week washout period. Twenty-four volunteers received a single dose of two tablets of the two different dexamethasone formulations. Blood samples for pharmacokinetic profiling were taken up to 24 h after drug administration in fasting condition. Plasma concentrations of dexamethasone were determined with a validated HPLC method using an ultraviolet detector. Pharmacokinetic parameters were calculated from observed plasma concentration-time profiles.


RESULTS
The mean AUC0-t, AUC0-infinity, and Cmax were 501.61 ng x h/ml, 518.88 ng x h/ ml and 98.02 ng/ml, respectively for the test formulation and 507.10 ng x h/ml, 525.20 ng x h/ml and 97.82 ng/ml, respectively, for the reference formulation. The median Tmax, for both formulations was 0.75 h. Plasma elimination half-lives (t1/2) were 3.44 h (test) and 3.38 h (reference). The point estimates and 90% confidence intervals (CI) for AUC0-t, AUC0-infinity and Cmax were 98.92% (94.62-103.41%), 98.80% (94.51-103.28%) and 100.20% (91.43-109.81%), respectively, satisfying the bioequivalence criteria of the European Committee for Proprietary Medicinal Products and the US Food and Drug Administration guidelines.


CONCLUSIONS
These results indicate that the two formulations of dexamethasone are bioequivalent and thus may be prescribed interchangeably.
Harahap
Yahdiana
Y
Department of Pharmacy, Faculty of Mathematic and Science, University of Indonesia, Depok, Indonesia.
Sasongko
Lucy
L
Prasaja
Budi
B
Indriati
Ega
E
Lusthom
Windy
W
Lipin
D000293:Adolescent; D000328:Adult; D000893:Anti-Inflammatory Agents / Q000008:administration & dosage / Q000493:pharmacokinetics*; D019540:Area Under Curve; D001682:Biological Availability; D002626:Chemistry, Pharmaceutical; D002851:Chromatography, High Pressure Liquid; D018592:Cross-Over Studies; D003907:Dexamethasone / Q000008:administration & dosage / Q000493:pharmacokinetics*; D005260:Female; D006801:Humans; D007214:Indonesia; D008297:Male; D013056:Spectrophotometry, Ultraviolet; D013607:Tablets; D055815:Young Adult
D000893:Anti-Inflammatory Agents; D013607:Tablets; D003907:Dexamethasone