ISSN 2490-3329 (Print)
ISSN 2303-7954 (Online)

Volume 49, Issue 1, Article 3

(Scr Med 2018:49:18-24)

Physicochemical Equivalence Studies of Two Amlodipine Tablet Formulations

Sanja Kecman1,2, Svetlana Goločorbin-Kon2,3, Momir Mikov2,4

¹ Hemofarm d.o.o, a Member of Stada Group,. Banja Luka, The Republic of Srpska, Bosnia and Herzegovina
2 Department of Pharmacy, Faculty of Medicine, University of BanjaLuka, Banja Luka, Republic of Srpska, Bosnia and Herzegovina
3 Department of Pharmacy, Faculty of Medicine, University of Novi Sad, Novi Sad, Serbia
4 Department of Pharmacology, Toxicology and Clinical Pharmacology, Faculty of Medicine, University of Novi Sad, Novi Sad, Serbia

doi: 10.18575/
UDC: 615.265.2
COBISS.RS-ID: 7316760


Introduction: Based on internationally drug regulatory requirements, all generic pharmaceutical manufacturers are obliged to ensure that their generic products are similar or equivalent to the innovative brand. Quality of generic medicines should be comparable with the innovator brand and therefore interchangeable with the innovator. Based on the Biopharmaceutical Classification System (BCS), dissolution tests can be used as a replacement for in vivo studies for drugs that belong to the BCS class I. Dissolution tests are considered the most sensitive in vitro parameters that can be with the highest probability of correlation with the in vivo bioavailability. Very often, comparison of dissolution tests in vitro, using similarity factor (f2) is used as the most important parameter that can reflect the existence of bioavailability.

Aim of the Study: The aim of this study was to compare physiscochemical characteristics of two amlodipine formulations made by the same manufacturer using the dissolution test and similarity factors to ascertain their in vitro similarity.

Material and Methods: Two different generic copies of amlodipine 5 mg tablets, produced by the same pharmaceutical manufacturer, were evaluated using pharmaceutical parameters such as: uniformity of active ingredient test, weight uniformity text, disintegration test, hardness test, tablet friability test, and in vitro dissolution test.

Results: The results showed that different salts and different manufacturing procedures do not have an effect on in vitro equivalence of amlodipine tablets.  The similarity factor (f2) at pH 4.5, 1.2 and 6.8  was 63.90, 53.87 and 57.57, respectively. Although these demonstrated equivalence, statistically significant differences were found in the degree of dissolution rates of tablets formulation depending on time and pH values. The results of our study showed equivalence of dissolution profiles of different amlodipine formulations.

Conclusion: The results of our study showed that the equivalence of dissolution profiles exists, although there were statistical differences in some pharmaceutical parameters.

Key words: amlodipine besylate, amlodipine mesylate, pharmaceutical formulation, dissolution

Pdf version of article

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Contact address:
Sanja Kecman,
Hemofarm doo,
Street address: Novakovići bb
78 000 Banja Luka,
Republic of Srpska,
Bosnia i Herzegovina
This e-mail address is being protected from spambots. You need JavaScript enabled to view it
phone number: +387-65-519-580

Submitted: March 6th, 2018
Accepted: March 18th, 2018