Metformin Hydrochloride/Pioglitazone Hydrochloride

A guide experimental design in chromatographic method development was described and applied successfully to the analysis of different recently approved anti-diabetic pharmaceutical combinations. Enhancement of UHPLC analysis of alogliptin benzoate either with pioglitazone hydrochloride or with metformin hydrochloride was achieved. The optimal chromatographic conditions were not attained by trial and error that requires a large number of experiments. Alternatively, a computer program was used as a systematic optimization strategy for the design of the experiment which accurately predicts the combined effect of different factors simultaneously. Resolution between peaks was studied by the proposed fractional factorial design approach performed by the Minitab® Program using screening and optimization steps. Application of the central composite design was implemented. A Pareto chart was used to exclude the insignificant variables. Linearity ranges were found to be 0.5-40 μg ml-1, 1-20 μg ml-1 and 1-32 μg ml-1 for alogliptin benzoate, pioglitazone hydrochloride and metformin hydrochloride, respectively. The proposed method is applicable for the analysis of six pharmaceutical dosage forms namely, Nesina®, Actos®, Glucophage®, Oseni®, Kazano® and Actoplus MET® tablets.

Carcinogenicity data of medicinal products for human use that have been authorised via the European centralised procedure (CP) between 1995 and 2009 were evaluated. Carcinogenicity data, either from long-term rodent carcinogenicity studies, transgenic mouse studies or repeat-dose toxicity studies were available for 144 active substances contained in 159 medicinal products. Out of these compounds, 94 (65%) were positive in at least one long-term carcinogenicity study or in repeat-dose toxicity studies. Fifty compounds (35%) showed no evidence of a carcinogenic potential. Out of the 94 compounds with positive findings in either carcinogenicity or repeat-dose toxicity studies, 33 were positive in both mice and rats, 40 were positive in rats only, and 21 were positive exclusively in mice. Long-term carcinogenicity studies in two rodent species were available for 116 compounds. Data from one long-term carcinogenicity study in rats and a transgenic mouse model were available for eight compounds. For 13 compounds, carcinogenicity data were generated in only one rodent species. One compound was exclusively tested in a transgenic mouse model. Six compounds were tumourigenic in repeat-dose toxicity studies in rats. The majority of tumour findings observed in rodent carcinogenicity studies were considered not to be relevant for humans, either due to a rodent-specific mechanism of carcinogenicity, a high safety margin between exposures at the NOAEL (No Observed Adverse Effect Level) in rodents and recommended therapeutic doses in humans, or based on historical control data, a small effect size and lack of dose-response relationship and tumours typically observed in rodent strains used, or were considered not to be relevant for humans based on literature and clinical data or likely differences in metabolism/local concentrations between rodents and humans. Due to the high number of rodent tumour findings with unlikely relevance for humans, the value of the currently used testing strategy for carcinogenicity appears questionable. A revision of the carcinogenicity testing paradigm is warranted.