IN VITRO BIOEQUIVALENCE STUDY ON TWO GENERIC BRANDS OF IBUPROFEN 200 MG TABLET IN IRAN MARKET

The study is a bioequivalence study aimed at assessing the equality of pharmaceutical characteristics between two different products. This research investigates the physicochemical properties and in vitro bioequivalence of various formulations of 200 mg ibuprofen tablets available in the Iranian market and the reference brand after entering the market.

Three formulations of ibuprofen tablets, including one foreign brand as reference and two domestic brands were selected. They were evaluated for the amount of active ingredient (assay), content uniformity, dissolution test according to USP, and the calculation of the difference factor (f1) and similarity factor (f2).

The assay test results for companies G1, G2, and the reference were 106.85%, 100.44%, and 104.8% of the claimed drug amount on the label, respectively. The acceptance value (AV) in the content uniformity test was 10.22, 25.8, and 10.57 for companies G1, G2, and the reference, respectively. In the dissolution test, the average percentage dissolution at the end of 60 minutes was 88.2%, 91.96%, and 92.74% for G1, G2, and the reference, respectively. The difference and similarity factors for G1 were 16.63 and 38.28, and for G2 were 6.06 and 82.51, respectively.

Based on the assay test, all three companies fall within the acceptable range of 90% to 110% of the label, confirming their compliance. In the content uniformity test, which requires an AV below 15, only brands G1 and the reference were approved. All brands were able to release more than 80% of the drug in the tolerance test. Additionally, concerning factors f1 and f2, which should respectively be below 15 and 50, only company G2 was confirmed. According to the results of the in vitro bioequivalence test, none of the generic brands examined have the ability for complete substitution with the reference brand. For company G1, the observed difference in dissolution may be related to differences in the type of coating between the test and reference products; in this case, an in vivo test is also necessary to demonstrate bioequivalence between these two products.