The Department of Health and Human Services and the World Health Organization (WHO) have established HIV regimens that include a variety of antiretroviral therapy (ART) medications for the treatment of HIV infected people. The Ministry of Health in Kazakhstan has authorized a clinical protocol (№97, 11.06.2020) for HIV treatment in accordance with WHO recommendations. For HIV treatment two types of ARV cocktails are recommended: preferable and alternative. The preferable is a combination of two NRTIs and INIs, whereas alternatives consist of two NRTIs' and one NNRTI. According to this protocol, ARV treatment should be administered no later than 14 days from the date of diagnosis, regardless of the clinical stage of the disease or CD4 cell count. The aim of the study was to analyze drug resistance mutations in 676 patients (52% men and 48% women) with HIV infection of subtype A6 living in different regions of Kazakhstan. ARV therapy was received by 18% of patients for less than 3 years; 48% - for 3-5 years; 24% for 6-8 years. The preferable ARV therapy was received by 49% of patients; 42.4% of patients received alternative therapy; 8.6% of patients took other types of cocktails. It was concluded that the main reason for the development of mutations of resistance to ARV drugs is insufficient adherence to the ARV therapy regimen. This may be due to difficulties in accessing medical care, stigmatization of HIV and a shortage of medicines due to exorbitant costs or other factors. The development of mutations of resistance to ARV drugs makes it difficult to maintain viral load suppression, creating a problem for the health of patients and at the same time increasing the risk of further HIV transmission.