ATP-binding cassette, sub-family B (MDR/TAP), member 1 (ABCB1) polymorphism and clopidogrel concentration in acute coronary syndrome: molecular change can explain the observed therapeutic concentration.

To the Editor,

Clopidogrel is the current widely used drug in acute coronary syndrome (1). The therapeutic level of clopidogrel is important for successful management of patients (2). Genetic underlying factor is mentioned as an important determinant for finalizing clopidogrel level. ATP-binding cassette, sub-family B (MDR/TAP), member 1 (ABCB1) polymorphism is mentioned for the interrelationship with clopidogrel concentration. Stokanovic et al. (3) studied ABCB1 C3435T polymorphism and found that “patients carrying at least one C allele achieved significantly higher serum concentration of clopidogrel.” In fact, the main action of any polymorphic form of ABCB1 is binding, which requires energy reaction. This concept is successfully used for explanation on the observed phenomenon in drug susceptibility and resistance (4). Based on the quantum energy calculation, the assessment of required energy can be useful for explanation of the observed final clopidogrel blood concentration. Focusing on each polymorphism at position 3435, the molecular weights of CC, CT, and TT genotypes are equal to 222.204, 237.215, and 252.227, respectively. Based on this information, the required energy for CC genotype will be the least, which further implies the best final clopidogrel level. This is concordant with the report by Stokanovic et al. (3).