Pharmaceutical Equivalence of Some Commercial Samples of Artesunate and Amodiaquine Tablets Sold in Southwestern Nigeria

Abstract

Purpose: To study the physical properties and dissolution profiles of commercial samples of artesunate and amodiaquine tablets. Methods: Fifteen generic brands of artesunate and five generic brands of amodiaquine tablets were obtained from drug retail outlets in Oyo and Ogun States in southwestern Nigeria. The tablets were subjected to various compendial tests including identification, weight uniformity, uniformity of content, content of active ingredient and uniformity of diameter. Additional tests used as a basis for the assessment of the pharmaceutical equivalence of the products include hardness, disintegration time and dissolution rate. Data obtained were analysed by correlation analysis, Chi-square and ANOVA. Results: Thirteen generic brands of artesunate (87 %) and four amodiaquine brands (80 %) investigated were imported. Two brands of the imported artesunate brands were found to contain undetectable amount of artesunate while another 8 samples contained overages. All the amodiaquine brands passed the assay test as stipulated by United States Pharmacopoeia (USP) for amodiaquine tablets while tablet disintegration time of amodiaquine products ranged from 5.8 -20.7 min. All but one artesunate sample passed the disintegration test too. A majority of the artesunate brands tested had significantly different dissolution profiles (p < 0.05). Four (80 %) of the amodiaquine tablet brands tested had similar dissolution profiles and percent drug released within 30 min (p > 0.05). One amodiaquine brand demonstrated poor dissolution profile as it did not meet minimum dissolution requirements within 30 min. Conclusion: The detection of substandard artesunate tablets and a poorly formulated amodiaquine tablet amongst the few sample brands studied highlights the need for increased drug surveillance and monitoring of the qualities of antimalarial medicines currently in use in order to prevent widespread treatment failure.

Anti-malarial medicine quality field studies and surveys: a systematic review of screening technologies used and reporting of findings

“…References standards are pure chemical compounds obtained from chemical manufacturing companies and are used by pharmacopeia such as USP as a basis for their official monographs for analysts to adopt. This review found that 15/39 (39%) studies stated using reference standards in the analytical process and reported on the source of the standard [ 30 , 35 , 38 – 42 , 45 , 46 , 49 , 65 , 67 , 76 , 78 , 79 ]. Of the 35/39 (89.7%) studies (excluding those that conducted visual inspection alone), 10/35 (29%) did not mention the source of the screening tests (and reagents), but simply named the device they were utilizing; MiniLab ® or a Raman handheld device [ 28 – 32 , 42 , 45 , 48 , 51 , 72 ].…”

“…A second operator to independently verify test results would enhance the validity of a study by minimizing the risk of operator error in results interpretation, particularly for the semi-quantitative TLC test in which there is a greater risk of misclassification bias. Overall, 31 studies used TLC, but only three reported using a second operator to verify results [ 38 , 69 , 75 ]. For 8/39 (21%) studies using visual inspection and/or colorimetry, a second operator would be unnecessary as results are more definitive in comparison to TLC.…”

“…Chemical tests included HPLC or Mass spectrometry (MS) (to assess content of the SAPI) or dissolution (medicine bioavailability). Of the 27 studies that reported the specific type of confirmatory tests they utilized, 12 conducted physical tests and also undertook chemical testing in parallel [ 32 – 35 , 37 , 38 , 40 , 41 , 52 , 72 ]. The remaining studies (15/27 (56%)) used chemical tests alone, either LC/MS or dissolution apparatus.…”

“…Only 11/30 (37%) studies employing confirmatory tests stated the source of the reference standards obtained [ 35 , 38 – 42 , 49 , 51 , 65 , 76 , 77 ] and just 14 stated the manufacturer of the analytical equipment [ 5 , 32 , 35 – 41 , 49 , 51 , 52 , 65 , 77 ]. In total, 7/27 (26%) studies that stated a using a specific type of confirmatory testing did not report using an international pharmacopeia [ 30 , 50 – 52 , 69 , 76 , 77 ].…”

Estudos De Equivalência Farmacêutica E Perfil De Dissolução Comparativo De Medicamentos Contendo Hidroclorotiazida

“…A intercambialidade entre os medicamentos Genéricos e de Referência tem sido amplamente discutida em publicações científicas (4)(5)(6)(7)(8). Storpirtis e cols.…”