Introduction:
The aim was to study the pharmacogenetic determinants of switching simvastatin-intolerant ethnic Uzbek patients with coronary artery disease (CAD) to rosuvastatin treatment.

Material and methods:
The study included 50 patients with CAD, who demonstrated statin-induced adverse liver symptoms, accompanied by an elevation in transaminase level (3-fold or more in 37 cases) or statin-induced adverse muscle symptoms, accompanied by elevations in serum (CK > 3 times above the upper limit of normal (ULN)) in simvastatin treatment with a dose of 10–20 mg/day. The control group consisted of 50 patients without side effects. Patients were genotyped for polymorphisms in the genes coding for the cytochrome P450 (CYP) metabolic enzymes CYP3A5(6986A>G), CYP2C9(430C>T), CYP2C9(1075A>C), and hepatic influx and efflux transporters SLCO1B1(521T>C) and BCRP(ABCG2, 421C>A) by means of the PCR-RFLP method.

Results:
When the 50 patients of the case group were switched to the starting rosuvastatin dose of 5 mg, intolerance symptoms were not observed in 29 (58%) versus 21 with adverse symptoms. In this case-control study, the groups differed significantly only in the prevalence of the *3/*3 genotype CYP3A5 (OR = 5.25; 95% CI: 1.6–17.8; p = 0.014).

Conclusions:
In a considerable proportion of ethnic Uzbek patients with CAD and simvastatin intolerance symptoms, serious side effects when switching to a starting dose of rosuvastatin were not observed, and it should be noted that in most cases (72.4%) this phenomenon was observed among the carriers of *3/*3 genotype of the CYP3A5 (6986A> G) gene.