A multicentre, open-label, randomized study of the gonadotrophin-releasing
hormone (
GnRH) antagonist
ganirelix (
Orgalutran((R))/
Antagon((TM))) was performed in women undergoing ovarian stimulation with recombinant FSH (rFSH:
Puregon((R))). The study was designed as a non-inferiority study using a long protocol of
buserelin (intranasal) and rFSH as a reference treatment. A total of 730 subjects was randomized in a treatment ratio of 2:1 (
ganirelix:
buserelin) using an interactive voice response system which stratified for age, type of
infertility and planned fertilization procedure [IVF or intracytoplasmic sperm injection (ICSI)]. The median duration of
GnRH analogue treatment was 5 days in the
ganirelix group and 26 days in the
buserelin group, whereas the median total rFSH dose was 1500 IU and 1800 IU respectively. In addition, in the
ganirelix group the mean duration of stimulation was 1 day shorter. During
ganirelix treatment the incidence of LH rises (LH >/=10 IU/l) was 2.8% versus 1.3% during rFSH stimulation in the
buserelin group. On the day of triggering ovulation by human chorionic gonadotrophin (HCG), the mean number of follicles >/=11 mm diameter was 10.7 and 11.8, and the median serum
oestradiol concentrations were 1190 pg/ml and 1700 pg/ml in the
ganirelix and
buserelin groups respectively. The mean number of oocytes per retrieval was 9.1 and 10.4 respectively, whereas the mean number of good quality embryos was 3.3 and 3.5 respectively. The fertilization rate was equal in both groups (62.1%), and the same mean number of embryos (2.2) was replaced. The mean implantation rates were 15.7% and 21.8%, and the ongoing pregnancy rates per attempt were 20.3% and 25.7% in the
ganirelix and
buserelin groups respectively. Evaluation of all safety data indicated that the
ganirelix regimen was safe and well tolerated. The overall incidence of
ovarian hyperstimulation syndrome was 2.4% in the
ganirelix group and 5.9% in the reference group. The results of this study support a safe, short and convenient treatment regimen of
ganirelix, resulting in a good clinical outcome for patients undergoing ovarian stimulation for IVF or ICSI.