Leuprolide Evidence Guide
Leuprolide (Lupron) is FDA-approved for prostate cancer, endometriosis, uterine fibroids, and precocious puberty - one of the broadest indication profiles of any peptide drug in this library. With 40+ years of clinical use and extensive Phase 3 data across multiple indications, it is the reference GnRH agonist. A highly validated compound by any standard.
Our Take
Leuprolide (Lupron) is FDA-approved for prostate cancer, endometriosis, uterine fibroids, and precocious puberty - one of the broadest indication profiles of any peptide drug in this library. With 40+ years of clinical use and extensive Phase 3 data across multiple indications, it is the reference GnRH agonist. A highly validated compound by any standard.
- Best for
- Prostate cancer hormone therapy, endometriosis, uterine fibroids, precocious puberty, GnRH agonist reference compound
- Evidence grade
- Level A
- Confidence
- High
- Starting point
- 7.5mg IM monthly (prostate cancer); 3.75mg IM monthly (endometriosis)
Benefits and Evidence
- Advanced Prostate Cancer: Level A, includes human evidence - Standard androgen deprivation therapy for advanced and metastatic prostate cancer. Achieves castrate testosterone in >93% of patients. Decades of clinical experience and RCT data support efficacy.
- Endometriosis Management: Level A, includes human evidence - Significantly reduces endometriosis-related pain and lesion size through estrogen suppression. Typically used for 6 months with hormonal add-back to mitigate bone loss and menopausal symptoms.
- Central Precocious Puberty: Level A, includes human evidence - First-line treatment for central precocious puberty. Suppresses premature pubertal development, reduces growth velocity to prepubertal rates, and preserves predicted adult height.
- Uterine Fibroid Shrinkage: Level A, includes human evidence - Pre-surgical treatment reduces fibroid volume by 35-65% over 3-6 months, facilitating less invasive surgery. Effect reverses after discontinuation.
Side Effects and Warnings
- Hot flashes (most common)
- Decreased libido
- Erectile dysfunction (males)
- Bone mineral density loss
- Injection site reactions
- Mood changes, irritability, depression
- Weight gain
- Fatigue and weakness
Research Dosage References
- <strong>Intramuscular or subcutaneous depot</strong> - 7.5 mg (monthly), 22.5 mg (3-month), 30 mg (4-month), 45 mg (6-month) - Per depot interval - Lupron Depot formulation. Injection by healthcare provider. Anti-androgen cover for first 2-4 weeks in prostate cancer to prevent flare.
- <strong>Subcutaneous (daily)</strong> - 1 mg/day - Daily - Used in IVF protocols and some pediatric applications. Less common than depot formulations.
- <strong>Subcutaneous implant</strong> - 65 mg - Every 12 months - Viadur implant for prostate cancer. Provides continuous release for one year. No longer widely available.
Mechanism of Action
Leuprolide achieves hormonal suppression via GnRH receptor desensitization: 1. Supraphysiological GnRH receptor activation: Binds pituitary GnRH receptors with high affinity, initially triggering a surge of LH, FSH, and downstream sex hormones (flare phase, 7-14 days). 2. Receptor desensitization and downregulation: Continuous occupancy leads to receptor internalization, uncoupling from G-proteins, and reduced receptor expression. 3. Gonadotropin suppression: LH and FSH fall to hypogonadal levels, eliminating the stimulus for gonadal steroid production. 4. End-organ effect: Testosterone falls below 50 ng/dL (surgical castrate level) in men; estradiol falls to menopausal levels in women. Achieves the therapeutic effect in hormone-dependent conditions.
Legal Status
FDA-approved prescription medication. Multiple formulations and brand names (Lupron, Eligard, Fensolvi). Not a controlled substance.
Primary Sources
- Leuprolide versus diethylstilbestrol for metastatic prostate cancer. New England Journal of Medicine, 1984.
- Depot leuprolide acetate for the treatment of endometriosis. Journal of Clinical Endocrinology & Metabolism, 1988.
- Long-term follow-up of central precocious puberty treated with GnRH analogs. Journal of Pediatric Endocrinology & Metabolism, 2008.