The aim of this study was to determine whether gonadotropin-releasing hormone (GnRH) antagonists (an emerging class of drugs to suppress testosterone synthesis in the treatment of prostate cancer) cause less adverse cardiovascular events than the more commonly use GnRH agonists.
Methods and results
We conducted a systematic review to identify all randomized, controlled trials in which a GnRH antagonist was compared with a GnRH agonist in men with prostate cancer. We identified 10 eligible studies including two different GnRH antagonists, degarelix (n = 1681) and relugolix (n = 734), which were compared with the GnRH agonists, leuprolide (n = 714) and goserelin (n = 600). The pooled risk ratios (95% confidence intervals) among GnRH antagonist recipients for adverse cardiovascular events, cardiovascular death, and all-cause mortality were 0.57 (0.39–0.81); 0.49 (0.25–0.96); and 0.48 (0.28–0.83), respectively. Important limitations of the included trials were their short duration of follow-up, unblinded study design and (in most of the studies) the identification of adverse cardiovascular events through safety reporting mechanisms rather than as a pre-specified outcome. There was no evidence of heterogeneity of findings among the studies.
There is consistent but methodologically limited data to suggest that GnRH antagonists—a relatively new class of androgen deprivation therapy for prostate cancer—cause significantly less cardiovascular adverse effects than the more frequently used GnRH agonists.