Osteoarthritis (OA) is the most common joint disease. Searching for new treatment methods and regimens for OA is relevant.Objective: to evaluate the efficiency and safety of therapy with a symptomatic sustained-release drug (Alflutop) in combination with intra-articular hyaluronic acid (HA) injection versus monotherapy with HA in patients with knee OA in routine clinical practice.Patients and methods. A post-registration open-labeled prospective comparative randomized study was conducted to assess the results of treatment in 76 patients (31 men and 45 women; mean age, 49.3±8.5 years; body mass index, 28.4±0.8 kg/m2 ) in two clinical centers in Yekaterinburg and Perm. The patients were randomized into two equal groups, were homogeneous in terms of gender, the frequency of comorbidities, and vital signs (blood pressure, heart rate, and respiratory rate).Group 1 patients received Alflutop as 1-ml daily intramuscular injections (a total of 20 injections) + 2 ml of 1% intraarticular (IA) HA solution injections three times at 1-week intervals; Group 2 patients were given 2 ml of 1% intraarticular HA solution injections three times at 1-week intervals. As an additional therapy, the use of meloxicam 7.5–15 mg/day was permitted, and, if non-steroidal anti-inflammatory drugs were contraindicated, paracetamol 1–3 g/day might be used.Results and discussion. During treatment, both groups of patients showed improvement (compared to the baseline levels). At the same time, evaluating the intergroup values revealed clear differences: a more pronounced decrease in all WOMAC indicators in Group 1 patients: pain scores, 2 [1; 3] vs. 4 [2; 5] in Group 2 (p