Product name: cetrorelix

Description: cetrorelix is used in assisted reproduction to inhibit premature luteinizing hormone surges. The drug works by blocking the action of GnRH upon the pituitary, thus rapidly suppressing the production and action of LH and FSH. It is administered as either multiple 0.25 mg daily subcutaneous injections or as a single-dose 3 mg subcutaneous injection. The duration of the 3 mg single dose is four days; if hCG is not administered within four days, a daily 0.25 mg dose is started and continued until hCG is administered.

Cetrorelix is marketed by Merck Serono as Cetrotide for use in in-vitro fertilization in all countries exceptJapan, where it is marketed by Shionogi and Nippon Kayaku. Aeterna Zentaris receives royalties on these sales and retains rights to develop cetrorelix for other indications. In IVF use it is injected daily after follicle stimulation has been initiated and evidence of follicle maturation is approaching; given daily it prevents an endogenous LH surge that would trigger an untimely ovulation prior to the hCG administration by the treating physician. As an alternative to the GNRH antagonist, also a GNRH agonist could be given, but agonist have to be started earlier to overcome the agonistic effect. Cetrorelix can be mixed with follitropin alpha without compromising their reported safety and efficacy.