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Bewertung der Einsparpotenziale in der Arzneimitteltherapie durch Dosisanpassung an die Polymorphismen im Cytochrom P450

Evaluation of economic savings in drug therapy by dose adjustment to polymorphisms in cytochrome P450

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PharmacoEconomics German Research Articles

Abstract

Objective: The cytochrome P450 superfamily is an important enzyme complex which aids in the metabolization of approximately 80% of pharmaceuticals currently on the market. Genetic variation leads to different phenotypes of metabolization: extensive metabolizer (EM), intermediate metabolizer (IM), poor metabolizer (PM) and ultra-rapid metabolizer (UM). Depending on polymorphism, different doses are appropriate. The information about 2D6, 2C9 and 2C19 is especially relevant from an economic point of view. The authors aim to determine how large the economic savings can be for the statutory health insurance by adapting the dose rate according to the CYP450 genotype. Therefore, they explored the top ten groups of the Anatomical Therapeutic Chemical (ATC) Classification System in sales in 2010.

Methods: To calculate potential savings, a formula was designed, which includes the relevant agents, the frequency in which polymorphisms occur, the average defined daily doses and their costs, the number of patients, and the average intake period.

Results: 36 appropriate agents were identified for calculation. They incurred a total cost of h2.3 billion for the statutory health insurance in 2010. The maximum saving potential lies in the ATC-group of psychoanaleptics, amounting to h96.1 million. Aripiprazol (h948.60), perphenazin (h352.40) and thiordiazin (€319.10) head the list of agents with the best saving potential per patient and treatment phase. Regarding the costs of diagnostic tests (€100 or €300), only four out of eight drugs are cost-covering.

Conclusion: Pharmacogenetic testing and subsequent dose optimization is partially efficient. Mainly for agents with high €/DDD (DDD: Defined Daily Dose) and long duration of treatment, positive cost-aspects have been calculated in total or on a per patient basis. For final economic appraisal, further information is needed, such as the effect on adverse drug reaction or synergy effects for multi-medicated patients. Finally, dose optimization based on genetic information is likely to be efficient for several agents.

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Meier, F., Kontekakis, A. & Schöffski, O. Bewertung der Einsparpotenziale in der Arzneimitteltherapie durch Dosisanpassung an die Polymorphismen im Cytochrom P450. Pharmacoeconomics-Ger-Res-Articles 10, 69–85 (2012). https://doi.org/10.1007/BF03320779

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