Degarelix. More rapid medical castration, nothing more

Abstract

In patients with non-localised prostate cancer, medical castration is generally achieved with a GnRH agonist such as triptorelin. A peripheral antiandrogen can be added during the first weeks of treatment to counteract the initial testosterone surge. Degarelix is the first GnRH antagonist to be authorised in this setting in the European Union. A randomised unblinded trial compared subcutaneous degarelix versus intramuscular leuprorelin, without the addition of a peripheral antiandrogen. Castration was achieved in almost all patients after the first month of treatment. Testosterone levels decreased within a few days with degarelix and more slowly with leuprorelin, after an initial surge, and these levels were maintained in both groups throughout the one-year study period. The more rapid fall in testosterone obtained with degarelix, without an initial surge, did not translate into lower mortality (there were only 2 cancer deaths) or fewer adverse effects during the first month of treatment. The main adverse effects in this trial were linked to castration: hot flushes and weight gain. Reactions at the injection site (pain, erythema) were far more frequent with degarelix than with leuprorelin, affecting respectively about 40% and fewer than 1% of patients. The large volume of the degarelix subcutaneous solution (3 to 4 mi) is not very practical to administer. In practice, degarelix has no tangible advantages over a GnRH agonist such as triptorelin. It is better to continue to use triptorelin, possibly with addition of an antiandrogen at the beginning of treatment.