Objective. To estimate changes in medication adherence in patients treated with fixed-dose combination of amlodipine/ indapamide/ perindopril arginine included in DOKAZATEL'STVO observational study. design and methods. Effects of the fixed-dose combination of amlodipine/ indapamide/ perindopril arginine on medication adherence were assessed in 1554 patients who filled in the questionnaire at baseline and at the last visit. Primary outcomes of the study included the change in the office and ambulatory (home blood pressure (BP) monitoring) systolic and diastolic BP from baseline to 3 months and rate of the achievement of target BP < 140/90 mmHg after 3-month treatment. Adherence was assessed by special questionnaire. Results. The fixed-dose combination of amlodipine/ indapamide/ perindopril arginine resulted in the decrease in systolic BP by 39.5 mmHg and diastolic BP by 18.8 mmHg after 3 months. Target office BP < 140/90 mmHg was achieved in 87 %. High adherence at baseline was observed in 7,1 % patients, after 3 months of treatment - in 38,3 % (p < 0,001). Mean adherence score increased from 2,9 ± 1,6 to 5,0 ± 1,1 (p < 0,001). Study drug intake was associated with increase in motivation and awareness from 38 % to 95,4 % and from 19,8 % to 67,3 %, respectively (p < 0,001 for trend). conclusions. The administration of the fixed-dose combination of amlodipine/ indapamide/ perindopril arginine was associated with well tolerated BP decrease and significant increase in medication adherence and motivation even in the absence of specific targeted interventions. © 2019 All-Russian Public Organization Antihypertensive League. All rights reserved.