Evaluation of CYP2C9- and VKORC1-based pharmacogenetic algorithm for warfarin dose in Gaza-Palestine

Abstract

Aim: To evaluate applicability of CYP2C9* 2,* 3 and VKORC1–1639G> A based algorithm to predict warfarin stable dose (WSD) in a group of Palestinian patients. Patients & methods: Warfarin doses were retrospectively calculated for 101 Palestinian patients under warfarin therapy using three models. Performance of the three models was assessed in 47 patients found to take WSD. Results: Frequency of CYP2C9* 2,* 3 and VKORC1–1639G> A alleles is 13.6, 0.0 and 46.5% respectively. The international warfarin pharmacogenetics consortium algorithm was more reliable (MAE= 8.9±1.4; R2= 0.350) than both the clinical algorithm (MAE= 10.4±1.4; R2= 0.128;) and the fixed-dose algorithm (MAE= 11.1±1.7). Conclusion: The international warfarin pharmacogenetics consortium algorithm can be reliably applied for predicting the WSD in Palestinian population.