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FDA-approved pamoate depots · indication-specific intervals
Triptorelin
Triptorelin labels give separate uses and schedules for Trelstar and Triptodur. Their doses cannot be added or used to infer other schedules.
- Trelstar and Triptodur have different approved uses.
- The long-acting strengths are not additive.
- These labels do not set a schedule for IVF or other studied uses.
Triptorelin is a gonadotropin-releasing hormone agonist. FDA substance records distinguish triptorelin base, triptorelin pamoate and triptorelin acetate. The current US products found for people contain the pamoate salt.
They are the depot products Trelstar and Triptodur.
The current Trelstar label covers advanced prostate cancer. It lists three schedules for injections into a muscle. These are 3.75 mg every four weeks or 11.25 mg every 12 weeks.
The third is 22.5 mg every 24 weeks. Those depot strengths release the drug differently. They are not additive.
The current Triptodur label covers central precocious puberty from age two years. It lists 22.5 mg into a muscle every 24 weeks. These pamoate schedules belong to those specific uses.
They do not set schedules for IVF or endometriosis. They also do not set schedules to preserve ovarian function or optimize hormones. Nor do they set schedules for acetate products.
What matters first
- The product and approved use determine the interval: Trelstar and Triptodur are pamoate depots. Their labels cover different patient groups. Matching strengths or intervals do not make those uses interchangeable.
- Trelstar strengths are not additive: The 3.75, 11.25 and 22.5 mg products release the drug differently. Each belongs to its intended four-, 12- or 24-week interval. They are not combined as multiples.
- Base, salt and preparation volume are separate: Triptodur contains 22.5 mg triptorelin base in one vial. This equals 31 mg triptorelin pamoate. That vial is reconstituted with 2 mL sterile water. These are not separate doses. The values cannot be added or divided to calculate a personal concentration.
- An early surge comes before hormone suppression: The Trelstar label describes an early testosterone rise. Sustained suppression follows. The clinical findings do not establish general testosterone optimization.
- Human research does not expand the approved labels: One IVF protocol studied daily triptorelin acetate. A depot study omitted its strength. Other cancer studies tested uses outside the approved labels. Each remains a research setting.
- OvuGel is for animals: Its label gives 100 micrograms of triptorelin base per mL. The drug is present as triptorelin acetate. It describes a 2 mL amount placed in the vagina of weaned sows. This is not a human acetate strength, route, dose or approval.
Identity, salts, and names
FDA substance records distinguish triptorelin, UNII 9081Y98W2V from triptorelin pamoate, UNII 08AN7WA2G0 and triptorelin acetate, UNII 43OFW291R9. The substance mappings also call pamoate embonate. These name records alone do not prove that a product is approved.
Trelstar and Triptodur are the current US human pamoate products found. Decapeptyl appears as a synonym for pamoate. It also appears in non-US or research trial records. A name match does not prove that a US product exists.
OvuGel contains the acetate salt but has an animal label. Each source keeps its salt and product. It also keeps its use.
Its route and strength basis also stay attached. So does the time between doses.
Trelstar for advanced prostate cancer
The current Trelstar FDA label lists triptorelin pamoate for advanced prostate cancer. It gives three schedules, each as one injection into a muscle. These are 3.75 mg every four weeks or 11.25 mg every 12 weeks.
The third is 22.5 mg every 24 weeks. The label says those strengths release the drug differently. They are not additive.
Each must be selected for its intended interval.
The label reports the strengths as triptorelin base. The active material is triptorelin pamoate. Each product has freeze-dried microgranules.
These are reconstituted with 2 mL sterile water and given promptly as a suspension. That water volume is a preparation step for the labeled product. It does not create a personal concentration calculation or a divisible dose.
The label describes an early testosterone surge. Sustained suppression follows:
- The 11.25 mg trial randomized 346 men. It compared 11.25 mg every 12 weeks with 3.75 mg every 28 days. In the 11.25 mg group, 97.7% reached testosterone at or below 50 ng/dL at day 29. From day 57 through day 253, 94.4% maintained that level.
- The 22.5 mg trial had no comparator. It enrolled 120 men who received two injections 24 weeks apart. At day 29, 97.5% had testosterone at or below 50 ng/dL. From day 57 through day 337, 93.3% maintained that level.
An original randomized active-control trial enrolled men with advanced prostate cancer. It assigned triptorelin 3.75 mg or leuprolide 7.5 mg into a muscle. The schedule was every 28 days for nine injections.
There were 284 treated men. At day 29, triptorelin reached the protocol’s castrate threshold less often. The rates were 91.2% versus 99.3%.
Mean and cumulative maintenance rates were equivalent from days 29–253. The study measured testosterone suppression. This alone does not show a broader benefit for function.
Triptodur for central precocious puberty
The current Triptodur FDA label lists triptorelin pamoate for central precocious puberty. It covers children age two years and older. The amount is 22.5 mg as one injection into a muscle.
The interval is every 24 weeks.
The supporting study was open-label and had no control group. It followed 44 previously untreated children age 2–9 years. There were 39 girls and five boys.
Follow-up covered two dosing intervals. At each time point measured, at least 93% met the label’s prepubertal stimulated-LH threshold. Sex-steroid and clinical-sign outcomes came from this same small uncontrolled group.
One vial contains 22.5 mg triptorelin. The label says this equals 31 mg triptorelin pamoate. The vial is reconstituted with 2 mL sterile water.
The base amount, salt equivalent and water volume describe one product. They are not additive or interchangeable doses.
Other human research contexts
IVF dose-finding study of triptorelin acetate
An IVF dose-finding trial randomized 240 women equally across four groups. These received placebo or triptorelin acetate 15, 50 or 100 micrograms daily. The long IVF protocol also used FSH for ovarian stimulation.
The checked abstract does not state the triptorelin route.
Premature LH surge occurred in 23% of the placebo group. It occurred in none of the triptorelin groups. The 50 and 100 microgram groups produced more oocytes and embryos.
Dose had no relationship with implantation, pregnancy or ongoing pregnancy. It also had none with live birth or baby take-home rates. This surrogate result concerns suppression within a multi-drug IVF protocol.
It does not establish a general fertility schedule. Nor does it establish a current approved human acetate product.
Endometriosis study with an unstated depot strength
A placebo-controlled endometriosis trial included 49 women with symptoms. Laparoscopy had confirmed their disease. They received triptorelin depot or placebo every four weeks for six months.
Planned observation followed.
Pain and lesion measures improved more with triptorelin. Side effects affected 80% of actively treated people, mainly hot flashes. Symptoms recurred.
For that reason, only five people could be observed for 12 months after treatment. The abstract does not state the depot strength. It cannot be borrowed from Trelstar, Triptodur or another study.
Ovarian-function preservation study stopped for low accrual
The NCT00090844 registry describes a randomized Phase 2 trial. It compared chemotherapy with or without Trelstar Depot 3.75 mg. The drug was given monthly into a muscle.
The women were premenopausal and had early-stage breast cancer. The primary outcome was time until periods resumed.
The study enrolled 49 rather than the planned 138. It stopped early because too few people enrolled. That reason is not a negative benefit result.
This cancer-treatment setting does not establish routine ovarian-preservation or fertility use.
Other terminated prostate-cancer studies
The NCT00415246 registry describes a Phase 3 prostate-cancer study without a control group. It tested a new under-the-skin four-month sustained-release formulation. Early data did not support sustained blood levels for four months in everyone.
The study stopped for that reason. The record names Decapeptyl and estimates enrollment at 100. It posts no results or delivered amount.
That finding concerns one form of the drug. It cannot be turned into a dose. It does not negate the separately approved pamoate depots injected into a muscle.
ANABRAQ, NCT01374087 randomized 32 men with recurrent prostate cancer after radiotherapy. It compared brachytherapy with or without one 22.5 mg triptorelin injection into a muscle. The preferred timing was two months before brachytherapy.
The trial stopped for slow enrollment; 31 men received treatment. The posted record says no analyses assessed biochemical failure-free survival or progression. Individual event rows cannot establish a comparative benefit.
Low enrollment or early closure does not prove a null effect. Only one study listed here stopped for a failed formulation property. That was the four-month sustained-release study.
Current US database check and OvuGel collision
FDA describes Drugs@FDA as its approved-product database. Its September 4, 2026 data page and 12-table archive list three prescription Trelstar products. They contain 3.75, 11.25 or 22.5 mg base equivalent per vial.
They also list one prescription Triptodur product at 22.5 mg base equivalent per vial. All four contain triptorelin pamoate. An exact openFDA ingredient query returns the same four human applications.
A current DailyMed search returns Trelstar, Triptodur and two OvuGel label records. The reviewed current OvuGel animal label lists an over-the-counter animal drug. It states “Not for Use in Humans” and identifies NADA 141-339.
OvuGel contains 100 micrograms of triptorelin base per mL. The drug is present as the acetate salt. The label gives a 2 mL amount placed in the vagina of weaned sows.
This is part of swine insemination. The strength is not 100 micrograms of triptorelin acetate per mL. That would mislabel the base as the salt.
Its strength, volume, route and animal use cannot transfer to people.
The current Drugs@FDA archive showed no approved human triptorelin-acetate product. This does not affect the approved pamoate products. It also makes no claim about approval around the world.
Reader questions
What forms of triptorelin are approved for people in the United States?
The current US human products found are pamoate depots. Trelstar covers advanced prostate cancer. Triptodur covers central precocious puberty from age two years.
Each product keeps its approved use, strength and release interval.
Can Trelstar strengths be added or substituted?
No. The label says 3.75, 11.25 and 22.5 mg release the drug differently. They are not additive.
The corresponding depot strengths have four-, 12- and 24-week schedules.
Is Triptodur 22.5 mg plus 31 mg of pamoate?
No. The label gives 22.5 mg triptorelin base per vial. This equals 31 mg triptorelin pamoate.
Both describe the same active material. The 2 mL sterile-water volume is for preparing that product. It is not another dose.
Does the IVF trial establish an approved triptorelin-acetate dose?
No. It tested 15, 50 or 100 micrograms daily. That was part of a multi-drug IVF protocol.
The checked abstract does not state the route. Current US approval searches found human pamoate products. They found no approved human acetate product.
What strength was used in the endometriosis trial?
The checked abstract does not say. It reports a depot every four weeks for six months. The strength cannot be taken from a different product or study.
Is OvuGel a human triptorelin-acetate product?
No. OvuGel is an animal drug for weaned sows. Its label says it is not for use in humans.
The 100 micrograms/mL figure refers to triptorelin base. The drug is present as the acetate salt. This is not a human strength or schedule.
Can these labels and trials be combined into a hormone-optimization plan?
No. The labels cover advanced prostate cancer and central precocious puberty. Other studies concern IVF, endometriosis, cancer treatment or formulation testing.
They do not set a general wellness or fertility schedule. Nor do they set a schedule to optimize hormones.