Ganirelix
Also known as: Ganirelix acetate, Antagon, Orgalutran, Fyremadel
A GnRH antagonist used during IVF ovarian stimulation to prevent a premature LH surge. FDA-approved in 1999; brand and generics. Prescription drug.
Last updated
Mechanism of Action
Ganirelix is a synthetic decapeptide that competitively blocks pituitary GnRH receptors. It suppresses LH and FSH secretion within hours without the initial stimulation seen with GnRH agonists. In controlled ovarian stimulation it is started partway through the cycle to prevent the premature LH surge that would cause early ovulation, and pituitary function recovers within about two days of the last dose.
- Half-life
- ~13-16 hours
- Administration Routes
- Subcutaneous
- Research Status
- Clinical
Reported Benefits
- Inhibition of premature LH surges in women undergoing controlled ovarian stimulation
- Shorter treatment course than long GnRH-agonist protocols
- Large follow-up studies of resulting pregnancies found no safety signal
Potential Side Effects
- Injection-site reactions
- Ovarian hyperstimulation syndrome (OHSS), related to the stimulation cycle
- Abdominal pain, headache and nausea
- Vaginal bleeding; rare hypersensitivity or anaphylactic reactions
Common Dosing
In the labeled regimen 250 mcg is injected subcutaneously once daily from the middle of the follicle-stimulation phase until the day of the ovulation trigger. It is supplied as a prefilled syringe, and timing is set by the fertility clinic based on ultrasound and hormone monitoring. Dosing is set and supervised by the prescribing clinician.
The dosing information above is aggregated from research literature and anecdotal community reports for educational purposes only. It is not a recommendation, prescription, or medical advice. Peptides are sold as research chemicals only and are not intended for human use.
Contraindications
- Hypersensitivity to ganirelix, GnRH or GnRH analogs
- Known or suspected pregnancy
No documented stacking partners for Ganirelix yet.
- View
Treatment with the gonadotrophin-releasing hormone antagonist ganirelix in women undergoing ovarian stimulation with recombinant follicle stimulating hormone is effective, safe and convenient: results of a controlled, randomized, multicentre trial. The European Orgalutran Study Group
2000
- View
Efficacy and safety of ganirelix acetate versus leuprolide acetate in women undergoing controlled ovarian hyperstimulation
2001
- View
Large prospective, pregnancy and infant follow-up trial assures the health of 1000 fetuses conceived after treatment with the GnRH antagonist ganirelix during controlled ovarian stimulation
2010