Leuprolide is a widely used GnRH agonist for unfavorable intermediate-risk prostate cancer because it provides reliable and sustained testosterone suppression, which enhances the effectiveness of radiation therapy. It is supported by decades of clinical data and is included in major guidelines (e.g., NCCN, AUA) as a standard ADT (Androgen Deprivation Therapy) agent.

Leuprolide is commonly chosen due to its flexible dosing schedules (monthly, 3-, 4-, or 6-month depot injections), broad insurance coverage, and ease of administration in both urology and oncology practices. While it initially causes a temporary testosterone surge (“flare”), this can be managed with short-term anti-androgens. It remains a first-line ADT option because of its balance of efficacy, clinical familiarity, and logistical convenience.