--- title: "Triptorelin" canonical_url: https://bestpeptidecalculator.app/library/triptorelin description: "FDA-approved depot GnRH agonist (Trelstar) for advanced prostate cancer. Causes flare then downregulation of LH/testosterone. WADA S2." updated: 2026-11-07 publisher: Peptide Library notice: "Research and educational use only. Not medical advice." --- # Triptorelin Triptorelin (also called Trelstar or Decapeptyl) is an FDA-approved depot GnRH agonist. Triptorelin is a GnRH agonist decapeptide with a D-tryptophan substitution at position six that increases receptor affinity and resists enzymatic degradation. FDA-approved depot GnRH agonist (Trelstar) for advanced prostate cancer. Causes flare then downregulation of LH/testosterone. WADA S2. Also known as: Trelstar, Decapeptyl, GnRH agonist. ## Classification - Type: FDA-approved depot GnRH agonist - Mechanism class: GnRH Modulator - Development stage: Approved product - Regulatory class: FDA-approved medicine ## Mechanism Triptorelin is a GnRH agonist decapeptide with a D-tryptophan substitution at position six that increases receptor affinity and resists enzymatic degradation. Given as a depot it provides continuous rather than pulsatile receptor occupancy, which first stimulates and then desensitises pituitary gonadotrophs: luteinising and follicle-stimulating hormone rise transiently, then fall as the receptor is downregulated, and gonadal steroid production declines to castrate concentrations over roughly two to four weeks. The same initial flare seen with other GnRH agonists occurs, and formulations are available giving one, three or six months of suppression. Targets: GnRH receptor. Origin: Synthetic decapeptide GnRH analog. ## Properties - Molecular formula: C64H82N18O13 - Molecular weight: 1,311.4 g/mol - CAS number: 57773-63-4 - Half-life: Depot: weeks to months - Studied routes: Intramuscular ## Evidence - Evidence level: FDA Approved - Highest documented: Regulatory review (FDA label) - Human trials: 1 - Controlled human trials: 1 - Preclinical sources: 0 - Latest source: 2024 Each step shows whether the sources Peptide Library has reviewed include that kind of research. Counts are reviewed sources, not every study ever published. Reviews and programme summaries that describe human use are shown as "reported", not as trials, and registered trials without published results are listed but not counted. A higher step means research has progressed further; it does not mean a compound works better or is safer. Compounds whose evidence has not been reviewed yet show "Not reviewed" instead of a guess. ### Studies 1. TRELSTAR (triptorelin pamoate for injectable suspension) — FDA prescribing information (Verity), DailyMed. Regulatory label (FDA), human. Population: Men with advanced prostate cancer. Treatment of advanced prostate cancer [Source](https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=b1b84d62-a369-a4b7-5c41-dd1f553a18f3) 2. TRIPTODUR (triptorelin) for extended-release injectable suspension — FDA prescribing information (Azurity), DailyMed. Regulatory label (FDA), human. Population: Children aged 2 and over with central precocious puberty. Suppression of LH and sex steroids [Source](https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=f41380e7-b830-432d-a5f5-a872932f107e) 3. Yu X et al. A Phase 3, Open-Label, Single-Arm Trial of the Efficacy and Safety of Triptorelin 6-Month Formulation in Chinese Children with Central Precocious Puberty. Adv Ther. 2024. 2024. Controlled human trial. Population: Chinese children with central precocious puberty (girls under 9, boys under 10; 66 completed). All patients had LH suppression (stimulated peak LH 5 IU/L or less) at month 6; 98.5% at month 12 [Source](https://pubmed.ncbi.nlm.nih.gov/39412628/) ## Safety Side effects: Hot flashes; Bone loss; Tumor flare; Injection-site reactions. Risks: WADA S2; Flare if unblocked. Human safety basis: FDA prescribing information ## Regulatory status Triptorelin is an FDA-approved product for specific labelled indications. Approval does not extend to the research contexts described on this page, and approved products are prescription medicines. - FDA status: Approved - WADA status: Banned in Sport - Availability: Prescription-Only ## Frequently asked questions ### What is Triptorelin? FDA-approved depot GnRH agonist (Trelstar) for advanced prostate cancer. Causes flare then downregulation of LH/testosterone. WADA S2. ### How does Triptorelin work? Triptorelin is a GnRH agonist decapeptide with a D-tryptophan substitution at position six that increases receptor affinity and resists enzymatic degradation. Given as a depot it provides continuous rather than pulsatile receptor occupancy, which first stimulates and then desensitises pituitary gonadotrophs: luteinising and follicle-stimulating hormone rise transiently, then fall as the receptor is downregulated, and gonadal steroid production declines to castrate concentrations over roughly two to four weeks. ### Is Triptorelin FDA approved? Yes. Triptorelin is approved by the FDA, and approved products are prescription medicines. Approval is always for specific indications studied in clinical trials, so an approved status does not mean the compound is approved for every use it is discussed for. Research-chemical material sold under the same name is not the approved product. ### What is the half-life of Triptorelin? Reported half-life for Triptorelin is Depot: weeks to months. Half-life describes how long the compound persists in circulation, not how long any effect lasts, and published figures vary with route of administration, formulation and the population studied. ### Is Triptorelin banned in sport? Triptorelin is recorded here as prohibited in sport. Athletes subject to anti-doping rules should check the current WADA Prohibited List directly, since it is revised annually and classifications change. ### What peptides are similar to Triptorelin? Compounds most often compared with Triptorelin include Leuprolide, Goserelin, Nafarelin and Histrelin. They are grouped by shared mechanism or research area rather than by equivalence, and their regulatory status and evidence base differ. ## References - [Trelstar label](https://www.accessdata.fda.gov/drugsatfda_docs/label/2024/020715s042lbl.pdf) - [WADA Prohibited List 2026](https://www.wada-ama.org/en/prohibited-list) - [A Phase 3, Open-Label, Single-Arm Trial of the Efficacy and Safety of Triptorelin 6-Month Formulation in Chinese Children with Central Precocious Puberty — Adv Ther, 2024](https://pubmed.ncbi.nlm.nih.gov/39412628/) - [Adolescent Gender Dysphoria in Italy: Reflections on Triptorelin, Consent, and Care — Clin Ter, 2025](https://pubmed.ncbi.nlm.nih.gov/40109078/) - [Triptorelin: The Need for Legal Protection Aimed at the Full Political and Social Integration of Gender Variant youth. A Comparison of Different Global realities — Clin Ter, 2025](https://pubmed.ncbi.nlm.nih.gov/41267605/) - [GnRH agonist treatment before total laparoscopic hysterectomy for large uteri — J Am Assoc Gynecol Laparosc, 2003](https://pubmed.ncbi.nlm.nih.gov/14567804/) - [Spotlight on triptorelin in the treatment of premenopausal women with early-stage breast cancer — Breast Cancer (Dove Med Press), 2018](https://pubmed.ncbi.nlm.nih.gov/29551913/)