Degarelix

Abstract

Degarelix is a gonadotropin-releasing hormone (GnRH) receptor antagonist that, in common with GnRH receptor agonists (e.g. leuprolide, goserelin and triptorelin), is indicated for use as an androgen-deprivation therapy in patients with advanced prostate cancer. In 1-year, randomized, open-label, phase II or III trials in patients with all stages of prostate cancer, subcutaneous degarelix was associated with rapid, profound and sustained suppression of serum testosterone and prostate-specific antigen (PSA), without evidence of testosterone surges or microsurges. In the phase III trial, degarelix (240 mg initially followed by 80 mg every 28 days) was considered to be effective and noninferior to intramuscular leuprolide (7.5 mg every 28 days) with regard to inducing and maintaining suppression of serum testosterone to castrate levels (i.e. <or=0.5 ng/mL). Degarelix induced testosterone suppression more rapidly than leuprolide. Median serum testosterone levels of <or=0.5 ng/mL were achieved by day 3 in degarelix recipients, but not until day 28 in leuprolide recipients. PSA suppression was also more rapid with degarelix than with leuprolide, with significant between-group differences in serum PSA levels favouring degarelix at 14 and 28 days. Degarelix treatment for 1 year was generally well tolerated; the adverse events reported were mostly related to subcutaneous drug administration (i.e. injection-site reactions) and hormonal androgen deprivation (e.g. hot flushes).