INTRODUCTION: Currently, for extensive occlusive lesions of the superficial femoral artery, the treatment of choice is femoropopliteal bypass grafting above the knee joint space. In the absence of a suitable autogenous vein or xenograft, synthetic grafts are used. One of the causes of thrombosis in the reconstruction zone after using synthetic grafts for femoropopliteal bypass grafting is the high incidence of restenosis in the anastomotic zone of arterial reconstruction due to endothelial dysfunction. One agent that normalizes endothelial function is a complex of bovine vascular regulatory polypeptides. STUDY OBJECTIVE: To evaluate the effectiveness of using a complex of regulatory polypeptides of bovine vessels after femoropopliteal bypass above the knee joint space with a synthetic prosthesis. MATERIAL AND METHODS: The study included 60 patients with stage III-IV lower extremity arterial atherosclerosis according to the Fontaine-Pokrovsky classification. They were divided into two groups of 30 patients each. All patients underwent surgery: femoropopliteal bypass grafting above the knee joint space using a synthetic prosthesis made of polytetrafluoroethylene diameter 8 мм. After surgery, patients in Group I, in addition to standard therapy, received one course of a drug based on a complex of bovine vascular regulatory polypeptides according to the instructions for use of Slavinorm® (intramuscular injections of the drug twice a week for 5 weeks, No. 10). Patients in Group II received only standard therapy according to clinical guidelines. To evaluate the effectiveness of treatment of patients, the following were used: measurement of the ankle-brachial index (ABI), ultrasound examination of the zones of the proximal and distal anastomoses of the femoropopliteal bypass, as well as measurement of the pain-free walking distance (PFWD) on the first day, 1, 3, 6, 9, 12 months after surgery. RESULTS: In groups I and II, the average ABI value before treatment was 0.46 and 0.44; 1 month after surgery 0.76 and 0.74; 3 months 0.77 and 0.71; 6 months 0.78 and 0.7; 9 months 0.785 and 0.7; 12 months 0.8 and 0.65, respectively. In groups I and II, the average DBH value before treatment was 31.5 m and 23 m; 1 month after surgery 118.5 m and 88 m; 3 months 128.5 m and 87 m; 6 months 128 m and 84 m; 9 months 134 m and 71 m; 12 months 138 m and 66 m, respectively. Changes in ABI and DBH in both groups throughout the entire follow-up period were statistically significant (p<0.001). Twelve months after surgery, the incidence of restenosis in Group I was 7 (11.6%) cases, while in Group II it was 15 (50%) cases. Postoperatively, at various follow-up periods, cases of BPS thrombosis were recorded: 1 (3.3%) case in Group I and 4 cases in Group II (13.3%). According to logistic regression data, in Group II patients who did not receive the bovine vascular polypeptide-based drug, the odds of developing restenosis in the arterial reconstruction zone were 3.25 times higher (OR 0.325, 95% CI 0.108-0.976, p=0.045) than in Group I patients. CONCLUSION: The use of regulatory polypeptides of bovine vessels after femoropopliteal bypass grafting above the knee joint space using a synthetic prosthesis reduced the incidence of restenosis of arterial reconstruction anastomosis zones by 3.25 times and, as a consequence, reduced the incidence of thrombosis of femoropopliteal bypass grafts.