Introduction
Cetrorelix is a man-made hormone that blocks the effects of Gonadotropin Releasing Hormone (GnRH). GnRH controls another hormone that is called luteinizing hormone (LH), which is the hormone that starts ovulation during the menstrual cycle. When undergoing hormone treatment sometimes premature ovulation can occur, leading to eggs that are not ready for fertilization to be released. Cetrorelix does not allow the premature release of these eggs to occur.
Uses
Cetrorelix is a synthetic peptide antagonist of gonadotropin releasing hormone used to prevent luteinizing hormone surges in women undergoing assisted reproduction therapy.
For the inhibition of premature LH surges in women undergoing controlled ovarian stimulation
Associated Conditions
Pharmacodynamics
Cetrorelix is a synthetic decapeptide with gonadotropin-releasing hormone (GnRH) antagonistic activity. GnRH induces the production and release of luteinizing hormone (LH) and follicle stimulating hormone (FSH) from the gonadotrophic cells of the anterior pituitary. Due to a positive estradiol (E2) feedback at midcycle, GnRH liberation is enhanced resulting in an LH-surge. This LH-surge induces the ovulation of the dominant follicle, resumption of oocyte meiosis and subsequently luteinization as indicated by rising progesterone levels. Cetrorelix competes with natural GnRH for binding to membrane receptors on pituitary cells and thus controls the release of LH and FSH in a dose-dependent manner.
Mechanism of Action
Cetrorelix binds to the gonadotropin releasing hormone receptor and acts as a potent inhibitor of gonadotropin secretion. It competes with natural GnRH for binding to membrane receptors on pituitary cells and thus controls the release of LH and FSH in a dose-dependent manner.
Absorption
Rapidly absorbed following subcutaneous injection. The mean absolute bioavailability following subcutaneous administration to healthy female subjects is 85%.
Volume of Distribution
- 1.16 L/kg
Protein Binding
86%
Route of Elimination
Following subcutaneous administration of 10 mg cetrorelix to males and females, only unchanged cetrorelix was detected in urine.
Half Life
~62.8 hours
Clearance
- 1.28 ml/min·kg [adult healthy female with 3 mg single SC administration]
Food Interactions
No interactions found.
