Efficacy of degarelix in prostate cancer patients following failure on luteinizing hormone-releasing hormone agonist treatment: results from an open-label, multicentre, uncontrolled, phase II trial (CS27).

Abstract

To evaluate the efficacy of second-line degarelix in patients with prostate cancer (PCa) after treatment failure with a luteinizing hormone-releasing hormone (LHRH) agonist. This 1-year exploratory, multicentre, open-label phase II trial was performed in 2 patient cohorts (Cohort 1, n = 25; Cohort 2, n = 12) in Germany. Patients with castrate-resistant PCa after primary hormonal treatment received degarelix 240 mg, followed by 11 monthly maintenance doses of 80 mg. The primary endpoint was the proportion of patients with decreasing/stable prostate-specific antigen (PSA) (relative change ⩽+10% of baseline PSA) after 3 months. At Month 3, the response rate (intention-to-treat, last observation carried forward analysis) was 16.7% [95% confidence interval (CI): 4.74-37.38] in Cohort 1 and 33.3% (95% CI: 9.92-65.11) in Cohort 2. The probability of completing 12 months without PSA progression was 8.8% (95% CI: 1.51-24.3) in Cohort 1 and 8.3% (95% CI: 0.5-31.1) in Cohort 2. Degarelix was well tolerated; the most frequently reported adverse events were local injection-site reactions. In PCa patients who failed LHRH therapy, degarelix was well tolerated and achieved a limited PSA response. Phase III trials show that disease control benefits with degarelix versus agonists are more clearly demonstrated as first-line therapy.