BACKGROUND: Endothelial dysfunction, a key factor in atherosclerotic vascular damage, increases cardiovascular risk in patients with psoriasis. However, studies on clinically measurable indicators of endothelial dysfunction and their changes during systemic therapy in psoriasis are limited and inconsistent. AIM: Сomparative assessment of the clinical effect of the IL-17 inhibitor Netakimab and Methotrexate on the values of laboratory markers of endothelial dysfunction in patients with psoriasis in comparison with the dynamics of clinical efficacy indicators over 6 months of therapy. MATERIALS AND METHODS: The study observed 66 PsA patients initially prescribed Methotrexate (Group 1: 30 patients) or Netakimab (Group 2: 36 patients). Group 1 received Methotrexate 15 mg weekly with Folic acid, while Group 2 received Netakimab 120 mg subcutaneously at weeks 0, 1, 2, then every 4 weeks. Clinical data were analyzed before, 3 months, and 6 months after treatment. Plasma levels of VEGF, endothelin-1 (En-1), and nitric oxide (NO) were measured before treatment and after 3 months. RESULTS: In psoriasis patients, plasma levels of endothelial dysfunction markers were higher than in the control group: VEGF (19.8 [4.5; 49.4] pg/ml vs. 5.2 [0.5; 9.8] pg/ml, p=0.004), En-1 (286.4 [154; 439] pg/ml vs. 96.5 [32; 188] pg/ml, p=0.002), and NO (4.3 [2.1; 12.5] pg/ml vs. 2.2 [0.2; 5.0] pg/ml, p=0.02). By the third month of therapy, VEGF, En-1, and NO levels decreased, with more significant reductions in Group 2: VEGF decreased by 10.2 [8.4; 13.7] vs. 7.0 [5.6; 11.7] (p=0.043) and En-1 by 184.6 [167; 202] vs. 112.7 [97; 136] (p=0.008) in Group 1. Group 2 also showed a more pronounced decrease in PASI and NAPSI scores at 3 and 6 months. CONCLUSION: The work demonstrated the ability of the IL-17 inhibitor netakimab to reduce initially elevated values of laboratory markers of endothelial dysfunction.