Source: FDA label
| Molecular formula | C64H82N18O13 |
|---|---|
| Molecular weight | 1311.4 g/mol |
| Registered trials | 310 |
| PubChem CID | 25074470 |
| Brand names | Trelstar |
Mechanism of Action
12.1 Mechanism of Action Triptorelin is a synthetic decapeptide agonist analog of gonadotropin releasing hormone (GnRH). Comparative in vitro studies showed that triptorelin was 100-fold more active than native GnRH in stimulating luteinizing hormone release from monolayers of dispersed rat pituitary cells in culture and 20-fold more active than native GnRH in displacing 125 I-GnRH from pituitary receptor sites. In animal studies, triptorelin pamoate was found to have 13‑fold higher luteinizing
Men diagnosed with advanced prostate cancer often want to understand how hormone-based therapies work before starting treatment. Triptorelin is one such option, and its approved use, mechanism, and safety data are outlined below.
Key takeaways
- Triptorelin is a synthetic GnRH agonist approved under the brand name Trelstar.
- It is indicated specifically for the treatment of advanced prostate cancer.
- More than 300 clinical trials have studied triptorelin or related GnRH agonist approaches.
- Reported adverse events include fatigue, hot flush, and disease progression, among others.
- The label does not carry a boxed warning.
What Triptorelin Is
Triptorelin is a synthetic decapeptide that mimics gonadotropin releasing hormone (GnRH), a natural hormone that regulates reproductive hormone signaling. Laboratory studies found it far more potent than natural GnRH at stimulating luteinizing hormone release from pituitary cells. By strongly activating GnRH receptors, triptorelin ultimately suppresses the downstream hormone signals that can drive certain hormone-sensitive conditions.
What Triptorelin Is Approved For
Triptorelin, marketed as Trelstar, is approved for the treatment of advanced prostate cancer. It belongs to the class of GnRH agonists, which work by altering the hormonal signals that support tumor growth in hormone-sensitive prostate cancer. The current label does not carry a boxed warning.
What the Evidence Shows
More than 310 registered clinical trials have investigated triptorelin or closely related GnRH agonist strategies across a range of conditions. Among the sampled studies, one completed Phase 2/3 trial examined endometrial injury and IVF outcomes in patients with prior failed IVF cycles. A recruiting Phase 2 trial is evaluating a GnRH agonist added to neoadjuvant chemotherapy in premenopausal patients with triple-negative early breast cancer.
Reported Side Effects
Adverse event reports submitted to FAERS for triptorelin include death (468 reports), off label use (395), and needle-related administration issues (227). Other frequently reported events include disease progression and fatigue (212 reports each), dose omission issues (203), hot flush (200), and drug ineffectiveness (190). These figures reflect the number of submitted reports, not confirmed incidence or proven causation, and many reports occur in patients with advanced underlying cancer.
FAQ
What is triptorelin used for?
Triptorelin, sold as Trelstar, is approved for the treatment of advanced prostate cancer. It works as a GnRH agonist that alters hormonal signaling involved in tumor growth. It is administered under medical supervision as part of a broader cancer treatment plan.
How does triptorelin work in the body?
Triptorelin is a synthetic version of gonadotropin releasing hormone (GnRH) that binds strongly to GnRH receptors. Laboratory studies showed it is far more potent than the body's natural GnRH at triggering hormone release from pituitary cells. This strong receptor activation eventually suppresses downstream reproductive hormone signaling.
Does triptorelin have a boxed warning?
No, the current triptorelin label does not carry a boxed warning.
What are the most commonly reported side effects of triptorelin?
FAERS reports for triptorelin most frequently mention death, off label use, and needle-related administration issues. Fatigue, disease progression, dose omission issues, hot flush, and drug ineffectiveness were also commonly reported. These are report counts submitted to a safety database, not confirmed rates of occurrence or evidence of direct causation.
Is there ongoing research involving triptorelin or similar GnRH agonists?
Yes, more than 310 clinical trials have studied triptorelin or related GnRH agonist approaches. Sampled studies include research on IVF outcomes after endometrial injury and a trial testing a GnRH agonist alongside chemotherapy in breast cancer patients. Trial status ranges from completed to actively recruiting.
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Content is editorial information, not medical advice. Talk to your doctor before any treatment decision.
Sources: FDA label (Trelstar) ClinicalTrials.gov FAERS adverse event reports PubChem
Updated 2026-09-19