Background. Prostate cancer (PCa) is an actual disease and a frequent oncological pathology in men. The main methods of radical treatment of patients with PCa are radical prostatectomy and radiation therapy. Radical prostatectomy s the most commonly used method of therapy in patients with localized PCa. Adjuvant hormone therapy after surgical treatment is the standard method of therapy in patients with the presence of lymph node metastases. At the same time, the standard approach of treatment of patients with metastatic PCa is combination therapy with medical (using of analogues or antagonists of luteinizing hormone-releasing hormone (LHRH) or surgical castration in combination with chemotherapy with docetaxel or new generation antiandrogens (enzalutamide or apalutamide)). Numerous studies have demonstrated the importance of achieving minimum testosterone levels at all stages of drug therapy in patients with PCa. It has also been shown that the use of LHRH analogues may be less effective to the use of LHRH antagonists (degarelix) in relation to the effectiveness of testosterone suppression. Thus, conducting a study aimed at studying the effectiveness of testosterone suppression using LHRH antagonists in various clinical situations and patient populations in real clinical practice is a very actual task.Aim. To evaluate the effectiveness and safety of castration therapy using degarelix in real clinical practice and in various clinical situations.Materials and methods. The object of an observational non-interventional study was 132 patients with PCa from 13 cancer centers of Russian Federation who were treated with LHRH antagonist degarelix. The study was non-interventional (observational), retrospectively-prospective, open multicenter and not randomized. In accordance with the design of the study, depending on the clinical situation, patients were divided into 3 groups: group A (n = 52; 39.4 %) – patients with primary metastatic hormone-sensitive PCa, who were shown to undergo combined drug treatment with castration therapy as one of the components; group B (n = 43; 32.6 %) – patients, who underwent combined hormonal and radiation treatment (ADT + radiation therapy); group C (n = 37; 28 %) – patients who underwent surgical treatment (radical prostatectomy with extended PLND) with the presence of metastases in the lymph nodes identified by the results of a morphological examination (pN1).Results and conclusion. As a result of a non-interventional observational study, high efficacy of androgen-deprivation therapy with the use of degarelix was demonstrated in relation to the suppression of testosterone and PSA in patients with primary metastatic and locally advanced PCa in various clinical situations, as well as low toxicity and satisfactory tolerability of this variant of hormonal treatment.