Skip to content
Dr. Grey AI

Peptide

Triptorelin (Trelstar)

Triptorelin is a synthetic decapeptide GnRH agonist. FDA-approved in 2000, available as 1-month (3.75mg), 3-month (11.25mg), and 6-month (22.5mg) formulations. Clinical trials show 97.5% achieve castrate testosterone by day 29 with 6-month formulation. 9-month survival significantly higher than leuprolide (97.0% vs 90.5%, p=0.033). Also approved for adjuvant breast cancer treatment.

Research notice. This page is for education and research. Peptides may not be FDA-approved for human use and may only be legally available for research. Talk to a qualified clinician before considering any peptide.

Best evidence
Grade A
Conditions studied
2
Outcomes
10
Graded outcomes
6211

Evidence by condition

  • Strong
  • Moderate
  • Limited
  • Very limited

2 conditions, plus general outcomes

Prostate Cancer: outcomes studied for Triptorelin (Trelstar)
GradeOutcomeEffectSizeStudiesPeopleStudies list
Overall Survival

9-month survival significantly higher than leuprolide (97.0% vs 90.5%; p=0.033). Low nadir testosterone associated with improved OS (p<0.001).

Improves (the measure goes up)Large effect17 studies

Studies that measured overall survival

and 7 more in the citations list

Testosterone Suppression

97.5% achieve castrate testosterone by day 29. Mean T of 12.8 ng/dL from month 2-12. Most potent GnRH agonist with lowest mean testosterone levels.

Improves (the measure goes down)Large effect11 studies

Studies that measured testosterone suppression

and 1 more in the citations list

PSA Suppression

Median PSA reduced by 96.4% at 12 months. Real-world data shows reduction from 117.9 to 8.5 ng/mL at 6 months.

Improves (the measure goes down)Large effect11 studies

Studies that measured psa suppression

and 1 more in the citations list

Breast Cancer: outcomes studied for Triptorelin (Trelstar)
GradeOutcomeEffectSizeStudiesPeopleStudies list
Disease-Free Survival (Breast)

SOFT/TEXT trials showed OFS plus tamoxifen provides significant DFS benefit in premenopausal patients. HOBOE trial validated efficacy.

Improves (the measure goes up)Moderate effect17 studies

Studies that measured disease-free survival (breast)

and 7 more in the citations list

Ovarian Function Suppression

Used in TEXT and SOFT trials for premenopausal breast cancer. Approved in EU and US for adjuvant treatment with tamoxifen or AI.

Improves (the measure goes down)Large effect11 studies

Studies that measured ovarian function suppression

and 1 more in the citations list

Ovarian Preservation

GIM/PROMISE-GIM6 study: reduces chemotherapy-induced early menopause. Enables fertility preservation in young breast cancer patients.

Improves (the measure goes up)Moderate effect11 studies

Studies that measured ovarian preservation

and 1 more in the citations list

General

General: outcomes studied for Triptorelin (Trelstar)
GradeOutcomeEffectSizeStudiesPeopleStudies list
Anti-Cancer Activity

16 human trials and systematic reviews support this finding. Evidence includes systematic reviews/meta-analyses. Human clinical trial data available.

Improves (the measure goes up)Moderate effect15 studies

Studies that measured anti-cancer activity

and 5 more in the citations list

Safety/Tolerability

5 human trials support this finding. Human clinical trial data available.

Improves (the measure goes up)Small effect10 studies

Studies that measured safety/tolerability

Reproductive Outcomes

10 systematic reviews and preclinical studies support this finding. Evidence includes systematic reviews/meta-analyses. Primarily preclinical evidence.

Improves (the measure goes up)Moderate effect15 studies

Studies that measured reproductive outcomes

and 5 more in the citations list

Hormone Levels

2 human trials support this finding. Human clinical trial data available.

Improves (the measure goes up)Small effect7 studies

Studies that measured hormone levels

Key findings

  • Overall SurvivalProstate CancerImproves (the measure goes up)
  • Disease-Free Survival (Breast)Breast CancerImproves (the measure goes up)
  • Testosterone SuppressionProstate CancerImproves (the measure goes down)

Studies cited

42 studies from PubMed

  1. Efficacy of Triptorelin Combined with Recombinant Human Growth Hormone (rhGH) on Serum Sex Hormones, Bone Age, and Clinical Outcomes in Girls with Precocious Puberty.British journal of hospital medicine (London, England : 2005), 2025 · PMID 39998154
  2. Testosterone nadir and clinical outcomes in patients with advanced prostate cancer: Post hoc analysis of triptorelin pamoate Phase III studiesProstate Cancer Prostatic Dis, 2024 · PMID 38481666
  3. PRIORITI: Phase 4 study of triptorelin or active surveillance in high-risk prostate cancerJ Clin Oncol, 2024 · PMID 38958195
  4. GnRH analogue triptorelin acetate induces ovulation in jennies during oestrus.Reproduction in domestic animals = Zuchthygiene, 2024 · PMID 38546114
  5. 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.Advances in therapy, 2024 · PMID 39412628
  6. Triptorelin nanoparticle-loaded microneedles for use in assisted reproductive technology.Drug delivery, 2023 · PMID 37387211
  7. The efficacy and safety of triptorelin-therapy following conservative surgery for deep infiltrating endometriosis: A multicenter, prospective, non-interventional study in China.Medicine, 2022 · PMID 35119037
  8. Assessment of Two Formulations of Triptorelin in Chinese Patients with Endometriosis: A Phase 3, Randomized Controlled Trial.Advances in therapy, 2022 · PMID 35947347
  9. Single injection of triptorelin or buserelin acetate in saline solution induces ovulation in mares the same as a single injection of hCG.Reproduction in domestic animals = Zuchthygiene, 2020 · PMID 31930759
  10. Spotlight on triptorelin in the treatment of premenopausal women with early-stage breast cancerBreast Cancer (Dove Med Press), 2018 · PMID 29551913
  11. Are all gonadotrophin-releasing hormone agonists equivalent for the treatment of prostate cancer? A systematic review.BJU international, 2018 · PMID 29438592
  12. Three cases of transient hyperthyroidism after triptorelin treatment - case report and literature review.Gynecological endocrinology : the official journal of the International Society of Gynecological Endocrinology, 2018 · PMID 29484896
  13. Luteinizing Hormone-Releasing Hormone Agonists are Superior to Subcapsular Orchiectomy in Lowering Testosterone Levels of Men with Prostate CancerJ Urol, 2017 · PMID 27939836
  14. Triptorelin: A Review of its Use as an Adjuvant Anticancer Therapy in Early Breast CancerDrugs Aging, 2017 · PMID 29177573
  15. Long-term effects of GnRH agonists on fertility and behaviour.Reproduction in domestic animals = Zuchthygiene, 2017 · PMID 28025851
  16. Meta-Analysis of Paediatric Patients with Central Precocious Puberty Treated with Intramuscular Triptorelin 11.25 mg 3-Month Prolonged-Release Formulation
.Hormone research in paediatrics, 2017 · PMID 28334719
  17. An Update on Triptorelin: Current Thinking on Androgen Deprivation Therapy for Prostate CancerAdv Urol, 2016 · PMID 27246172
  18. Twelve-Month Estrogen Levels in Premenopausal Women With Hormone Receptor-Positive Breast Cancer Receiving Adjuvant Triptorelin Plus Exemestane or Tamoxifen in the Suppression of Ovarian Function Trial (SOFT): The SOFT-EST SubstudyJ Clin Oncol, 2016 · PMID 26729437
  19. Efficacy and safety of triptorelin 6-month formulation in patients with central precocious puberty.Journal of pediatric endocrinology & metabolism : JPEM, 2016 · PMID 26887034
  20. A 6-Month Trial of the Efficacy and Safety of Triptorelin Pamoate (11.25 mg) Every 3 Months in Children with Precocious Puberty: A Retrospective Comparison with Triptorelin Acetate.Hormone research in paediatrics, 2016 · PMID 27603324
  21. Ovarian Suppression With Triptorelin During Adjuvant Breast Cancer Chemotherapy and Long-term Ovarian Function, Pregnancies, and Disease-Free Survival: A Randomized Clinical TrialJAMA, 2015 · PMID 26720025
  22. Prevention of Premature Menopause and Preservation of Fertility in Young Cancer Survivors: Hopeful Though Modest Long-term Results.JAMA, 2015 · PMID 26720024
  23. Perfecting breast-cancer treatment--incremental gains and musculoskeletal pains.The New England journal of medicine, 2015 · PMID 25495491
  24. Pituitary apoplexy induced by triptorelin in patient with prostate cancer.Endocrinologia y nutricion : organo de la Sociedad Espanola de Endocrinologia y Nutricion, 2015 · PMID 26184059
  25. Comparison of dienogest versus triptorelin acetate in premenopausal women with adenomyosis: a prospective clinical trial.Archives of gynecology and obstetrics, 2015 · PMID 25990480
  26. [Role of GnRH agonists in preserving female fertility].Journal de gynecologie, obstetrique et biologie de la reproduction, 2014 · PMID 24321862
  27. Suppression of fertility in pre-pubertal dogs and cats.Reproduction in domestic animals = Zuchthygiene, 2014 · PMID 24947857
  28. Hormone therapy in premenopausal women with early-stage breast cancer.The New England journal of medicine, 2014 · PMID 25006724
  29. An analytical strategy to characterize the pharmacokinetics and pharmacodynamics of triptorelin in rats based on simultaneous LC-MS/MS analysis of triptorelin and endogenous testosterone in rat plasma.Analytical and bioanalytical chemistry, 2014 · PMID 24510211
  30. Clinical use of deslorelin (GnRH agonist) in companion animals: a review.Reproduction in domestic animals = Zuchthygiene, 2014 · PMID 25277434
  31. Randomized trial using gonadotropin-releasing hormone agonist triptorelin for the preservation of ovarian function during (neo)adjuvant chemotherapy for breast cancerJ Clin Oncol, 2013 · PMID 22231041
  32. Triptorelin in the management of prostate cancer.Future oncology (London, England), 2013 · PMID 23252566
  33. It's all in the timing: ovulation induction in the mare.The Veterinary record, 2012 · PMID 22634892
  34. Effect of the gonadotropin-releasing hormone analogue triptorelin on the occurrence of chemotherapy-induced early menopause in premenopausal women with breast cancer: a randomized trialJAMA, 2011 · PMID 21771987
  35. Reproductive endocrinology: triptorelin ovarian suppression during breast cancer chemotherapy.Nature reviews. Endocrinology, 2011 · PMID 21931373
  36. Triptorelin embonate: a 6-month formulation for prostate cancer.Expert opinion on pharmacotherapy, 2010 · PMID 20969451
  37. Triptorelin 6-month formulation in the management of patients with locally advanced and metastatic prostate cancer: an open-label, non-comparative, multicentre, phase III studyClin Drug Investig, 2009 · PMID 19888782
  38. Leuprorelin, triptorelin: new indications. Locally advanced prostate cancer: minimally assessed me-toos.Prescrire international, 2007 · PMID 18092407
  39. [Clinical trial on the effectiveness and safety of triptorelin in treatment of uterine leiomyoma].Zhonghua fu chan ke za zhi, 2005 · PMID 16080872
  40. Comparative efficacy of triptorelin pamoate and leuprolide acetate in men with advanced prostate cancerUrology, 2003 · PMID 12887472
  41. Triptorelin approved for prostate cancer treatment.American journal of health-system pharmacy : AJHP : official journal of the American Society of Health-System Pharmacists, 2000 · PMID 10938976
  42. Triptorelin acetate administration in early pregnancy: case reports and review of the literature.European journal of obstetrics, gynecology, and reproductive biology, 1998 · PMID 9846657