Objective: to evaluate the efficacy and safety of simultaneous intramuscular administration of Traumeel® S and Zeel® T followed by therapy with the tablet medication Zeel® T in patients with knee osteoarthritis (OA) and concomitant cardiovascular diseases. Material and methods. The analysis included 119 patients aged 45–79 years (78.2 % women and 21.8 % men) with confirmed diagnosis of knee OA according to Altman criteria, stage II–III according to Kellgren–Lawrence and confirmed cardiovascular disease. The main indicator of efficacy was the change in pain intensity in the target knee joint according to the “Pain” subscale of the WOMAC questionnaire (A) at the final examination compared to the baseline. Other criteria were the dynamics of each symptom of knee OA according to the WOMAC questionnaire (pain, stiffness, and functional impairment, total score) on each visit, pain intensity in the target joint on a visual analogue scale (VAS), time it takes to travel 15 m, and the patient's overall disease assessment on the VAS. In addition, duration of use and dose of paracetamol (if used) were assessed, as well as quality of life by EuroQol and adverse events (AEs). Treatment safety was also analyzed in patients who had received at least one dose of the study drug. Results and discussion. WOMAC pain intensity decreased by on average of 3.8 points: from 7.6 to 3.8 points (95 % confidence interval, CI from -4.3 to -3.3). Data on changes in knee OA symptoms (pain, stiffness, and functional impairment) for each WOMAC subscale and the total score showed significant improvement at each follow-up visit (p < 0.0001). The VAS pain level decreased by 52%. An improvement in joint function was noted: the time it takes to travel 15 m fell from 19.5 to 16.4 s (p < 0.0001). The EuroQol quality of life score also improved from 57.1 ± 16.2 points at baseline to 71.1 ± 14.8 points on the 84<sup>th</sup> day of therapy. Thirty (25.2 %) patients had AEs, mainly neurological: headache (7.6 %) and hypoesthesia (1.7 %). No serious AEs were recorded. An association between AEs and study drug use was noted in 4 patients (headache, hypoesthesia, muscle cramps, and injection site pain). Conclusion. The results of the study confirm the efficacy and safety of the use of Traumeel® S and Zeel® T in patients with knee OA who have concomitant cardiovascular disease. During therapy, a significant decrease in pain and other clinical signs of OA (stiffness, limitation of physical activity) was observed, which allows us to recommend this treatment regimen for patients with comorbid pathology, as well as with the risk of developing of AEs during non-steroidal anti-inflammatory drugs therapy.