High prevalence of the UGT1A1*28 variant in HIV-infected individuals in Greece.

Hyperbilirubinaemia with or without jaundice is one of the side effects of atazanavir boosted with low-dose ritonavir (ATV/rit) related to the drug plasma levels, as a result of its metabolism by UGT1A1 - uridine diphosphate-glucuronosyl transferase. Genotyping for UGT1A128 before initiation of antiretroviral therapy containing atazanavir may aid in identifying individuals at risk of hyperbilirubinaemia. Our objective was to estimate the prevalence of the UGTA1A128 polymorphism in HIV-infected individuals in Greece and to determine its potential association with hyperbilirubinaemia in patients receiving ATV/rit. The prevalence of the UGTA1A128 variant was estimated in 79 HIV-infected patients prior to the administration of the first-line treatment. The UGTA1A128 variant was detected in 46 out of 79 individuals (58.2%). Antiretroviral therapy was administered to 64/79 patients (81%). Among them, 26/64 (40.6%) received ATV/rit. Of the ATV/rit-treated patients, 14 were found to be carriers of the UGT1A1*28 variant (54%), and maximum serum bilirubin levels were significantly higher in the carrier population (4.71 vs. 2.69 mg/dL, p = 0.026). In 50% of the population, maximum levels were recorded in the first month of follow-up. Although carriage of UGT1A1 is linked with the development of hyperbilirubinaemia, the implementation of a pharmacogenomic approach in clinical practice cannot yet be recommended as a standard of care.