A review of clinical evidence to assess differences in efficacy and safety of luteinizing hormone-releasing hormone (LHRH) agonist (goserelin) and LHRH antagonist (degarelix).

Luteinizing hormone-releasing hormone agonist (LHRH-A), goserelin, and antagonist, degarelix, are both indicated for the treatment of advanced prostate cancer (PCa); however, large comparative trials evaluating their efficacy and safety are lacking. In this review, we assessed the available evidence for both the drugs. Although degarelix achieves an early rapid decline in testosterone (T) and prostate-specific antigen (PSA) levels, median T and PSA levels, in addition to prostate volume and International Prostate Symptom Scores, become comparable with goserelin over the remaining treatment period. Degarelix causes no initial flare, therefore it is recommended in patients with spinal metastases or ureteric obstruction. Goserelin achieves lower PSA, improved time to progression, and better survival outcomes when administered adjunctively to radiotherapy compared with radiotherapy alone, with significant results even over long-term follow-up. The evidence supporting adjuvant degarelix use is limited. Goserelin has better injection site safety, single-step delivery, and an efficient administration schedule compared with degarelix, which has significantly higher injection site reactions and less efficient administration mechanism. There is conflicting evidence about the risk of cardiovascular disease (CVD), and caution is required when using LHRH-A in patients with preexisting CVD. There is considerable long-term evidence for goserelin in patients with advanced PCa, with degarelix being a more recent option. The available comparative evidence of goserelin versus degarelix has several inherent limitations related to study design, sample size, conduct, and statistical analyses, and hence warrants robust prospective trials and long-term follow-up.