Cetrorelix acetate

Cetrorelix acetate is an analogue of GnRH with amino acid substitutions at residues 1, 2, 3, 6, and 10 and differing from ganirelix at amino acids 1, 6, and 8. Each of these substitutions are synthetic, non-DNA-directed amino acids and, like ganirelix acetate, impart GnRH antagonist activity to cetrorelix acetate. This drug also is marketed for use in women undergoing assisted reproductive therapy (ART) procedures, in which it is necessary to control their LH surge. This allows the follicles to develop to a size, as determined by ultrasound, that increases the success of timed insemination and oocyte retrieval for IVF. Like ganirelix acetate, cetrorelix acetate has an advantage over GnRH agonists, such as leuprolide acetate, because it reduces the fertility therapy cycle to days rather than weeks.