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Comparative bioavailability study of a generic sustained release diclofenac sodium tablet
E Magosso1, K H Yuen, W P Choy
1School of Pharmaceutical Sciences, Universiti Sains Malaysia, 11800 Penang, Malaysia.
The Medical Journal of Malaysia
|February 25, 2005
Summary
The generic diclofenac sodium sustained release tablet (Zolterol, SR) showed comparable bioavailability to the innovator product (Voltaren, SR). This suggests bioequivalence between the two diclofenac formulations.
Area of Science:
- Pharmacokinetics
- Pharmaceutical Sciences
- Drug Bioavailability
Background:
- Diclofenac sodium is a widely used nonsteroidal anti-inflammatory drug (NSAID).
- Sustained release formulations aim to provide prolonged therapeutic effects.
- Generic drug manufacturing requires demonstrating bioequivalence to innovator products.
Purpose of the Study:
- To compare the bioavailability of a generic diclofenac sodium sustained release tablet (Zolterol, SR) with the innovator product (Voltaren, SR).
- To establish bioequivalence between Zolterol, SR and Voltaren, SR.
Main Methods:
- A randomized, two-way crossover study involving twelve healthy adult male volunteers.
- Pharmacokinetic parameters including area under the plasma concentration-time curve (AUC(0-infinity)), peak plasma concentration (Cmax), and time to peak plasma concentration (Tmax) were measured.
- A one-week washout period was implemented between treatments.
Main Results:
- No statistically significant differences were found in the logarithmically transformed AUC(0-infinity) between Zolterol, SR and Voltaren, SR.
- Peak plasma concentration (Cmax) values were not significantly different between the two diclofenac formulations.
- The time to reach peak plasma concentration (Tmax) was comparable for both sustained release preparations.
Conclusions:
- The generic diclofenac sodium sustained release tablet (Zolterol, SR) is bioequivalent to the innovator product (Voltaren, SR).
- These findings support the therapeutic interchangeability of Zolterol, SR and Voltaren, SR.
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