Treatment with the gonadotrophin-releasing hormone antagonist ganirelix inwomen undergoing ovarian stimulation with recombinant follicle stimulatinghormone is effective, safe and convenient: results of a controlled, randomized, multicentre trial

A multicentre, open-label, randomized study of the gonadotrophin-releasing hormone (GnRH) antagonist ganirelix (Orgalutran(R)/Antagon(TM)) was perform ed in women undergoing ovarian stimulation with recombinant FSH (rFSH: Pure gon(R)), The study was designed as a non-inferiority study using a long pro tocol of buserelin (intranasal) and rFSH as a reference treatment. A total of 730 subjects was randomized in a treatment ratio of 2:1 (ganirelix:buser elin) using an interactive voice response system which stratified for age, type of infertility and planned fertilization procedure [IVF or intracytopl asmic sperm injection (ICSI)]. The median duration of GnRH analogue treatme nt was 5 days in the ganirelix group and 26 days in the buserelin group, wh ereas the median total rFSH dose was 1500 IU and 1800 IU respectively. In a ddition, in the ganirelix group the mean duration of stimulation was 1 day shorter. During ganirelix treatment the incidence of LH rises (LH greater t han or equal to 10 IU/l) was 2.8% versus 1.3% during rFSH stimulation in th e buserelin group. On the day of triggering ovulation by human chorionic go nadotrophin (HCG), the mean number of follicles greater than or equal to 11 mm diameter was 10.7 and 11.8, and the median serum oestradiol concentrati ons were 1190 pg/ml and 1700 pg/ml in the ganirelix and buserelin groups re spectively. The mean number of oocytes per retrieval was 9.1 and 10.4 respe ctively, whereas the mean number of good quality embryos was 3.3 and 3.5 re spectively. The fertilization rate was equal in both groups (62.1%), and th e same mean number of embryos (2.2) was replaced. The mean implantation rat es were 15.7% and 21.8%, and the ongoing pregnancy rates per attempt were 2 0.3% and 25.7% in the ganirelix and buserelin groups respectively. Evaluati on of all safety data indicated that the ganirelix regimen was safe and wel l tolerated, The overall incidence of ovarian hyperstimulation syndrome was 2.4% in the ganirelix group and 5.9% in the reference group. The results o f this study support a safe, short and convenient treatment regimen of gani relix, resulting in a good clinical outcome for patients undergoing ovarian stimulation for IVF or ICSI.