A randomized dose-response trial of a single injection of corifollitropin alfa to sustain multifollicular growth during controlled ovarian stimulation. Induction of multiple follicular development by a single dose of long-acting recombinant follicle-Stimulating hormone (FSH-CTP, corifollitropin alfa) for controlled ovarian stimulation before in vitro fertilization. A double-blind, non-inferiority RCT comparing corifollitropin alfa and recombinant FSH during the first seven days of ovarian stimulation using a GnRH antagonist protocol. Corifollitropin alfa for ovarian stimulation in IVF: a randomized trial in lower-body-weight women.
This study primarily investigated the dose-response relationship of corifollitropin alfa to initiate multifollicular development for the first 7 days of controlled ovarian stimulation (COS).
                Women aged 20-39 years undergoing COS for in vitro fertilization or intracytoplasmic sperm injection were randomized to a single dose of corifollitropin alfa 60, 120 or 180 microg, or daily injections of 150 IU recombinant follicle-stimulating hormone (rFSH). Patients treated with corifollitropin alfa started fixed daily treatment with 150 IU rFSH on stimulation Day 8. Patients received a GnRH antagonist (ganirelix 0.25 mg/day) from stimulation Day 5 until the day of human chorionic gonadotrophin.
                Pharmacokinetics of corifollitropin alfa were dose-proportional. The main reason for not having embryo transfer was insufficient ovarian response in 30.8, 2.6, 3.8 and 7.4% of patients in the corifollitropin alfa 60, 120, 180 microg and rFSH groups, respectively. On Day 8, the mean (standard deviation) number of follicles >or=11 mm was 6.8 (4.4), 10.1 (6.1) and 12.8 (7.5), respectively. The number of cumulus-oocyte complexes retrieved showed a clear dose-response relationship (P < 0.0001), being 5.2 (5.5), 10.3 (6.3) and 12.5 (8.0) in the three dose groups, respectively.
                A single injection of corifollitropin alfa induces dose-related increase in multifollicular development and in the number of retrieved oocytes. The optimal dose for a 1-week interval is higher than 60 microg and lower than 180 microg and will be selected based on modelling and simulation taking into account insufficient stimulation as well as overstimulation. Clinical Trials gov: NCT00598208. In a first feasibility study, the efficacy and safety of a single dose of recombinant long-acting FSH (FSH-CTP) were investigated in in vitro fertilization (IVF) patients undergoing controlled ovarian stimulation with a flexible GnRH antagonist protocol. Eligible subjects were randomized to receive a single dose of 120 micro g (n = 25), 180 microg (n = 24), or 240 microg (n = 25) corifollitropin alfa (FSH-CTP) or to start daily fixed doses of 150 IU recombinant FSH (rFSH) (n = 24, reference). Subjects who received a single dose of FSH-CTP continued 1 wk after injection (treatment d 8) with fixed daily doses of 150 IU rFSH (Puregon/Follistim) until the day of triggering final oocyte maturation. The terminal half-life of FSH-CTP was, on average, 65 h and dose independent. Cycle cancellation before human chorionic gonadotropin (hCG) administration occurred in only three subjects treated with FSH-CTP. The median duration of stimulation was 10.0 d in each FSH-CTP group and 9.0 d in the daily rFSH group. The total number of follicles at least 11 mm at stimulation d 8 and at the day of hCG administration tended to increase with dose of FSH-CTP, although a significant dose-response relationship was revealed only for the number of follicles at least 15 mm on the day of hCG (P = 0.03). Serum estradiol levels and inhibin-B levels were not significantly different between the four groups on d 8 and on the day of hCG. In total, 12 subjects (17.6%) in the FSH-CTP groups and two subjects (8.3%) in the rFSH group experienced a premature LH rise (defined as LH >or= 10 IU/liter) before the start of the GnRH antagonist (P value not significant between groups). This relatively high incidence of women demonstrating an early LH rise in the FSH-CTP groups may be related to the higher initial rises of serum estradiol and the use of a flexible GnRH antagonist protocol. The mean number of oocytes recovered per started cycle was higher in FSH-CTP-treated subjects compared with rFSH-treated subjects (significant at P = 0.03 for the 240- microg FSH-CTP group), but no difference could be noted between the number of good quality embryos (range of means, 3.8-4.8 per attempt), and equal numbers of embryos were available for embryo transfer. In summary, FSH-CTP appeared to be a potent inducer of multiple follicular growth; additional research will be needed to select the optimal FSH-CTP dose and treatment time interval. Corifollitropin alfa, a fusion protein lacking LH activity, has a longer elimination half-life and extended time to peak levels than recombinant FSH (rFSH). A single injection of corifollitropin alfa may replace seven daily gonadotrophin injections during the first week of ovarian stimulation.
                In this large, double-blind, randomized, non-inferiority trial the ongoing pregnancy rates were assessed after one injection of 150 microg corifollitropin alfa during the first week of stimulation and compared with daily injections of 200 IU rFSH using a standard GnRH antagonist protocol.
                The study population comprised 1506 treated patients with mean age of 31.5 years and body weight of 68.6 kg. Ongoing pregnancy rates of 38.9% for the corifollitropin alfa group and 38.1% for rFSH were achieved, with an estimated non-significant difference of 0.9% [95% confidence interval (CI): -3.9; 5.7] in favor of corifollitropin alfa. Stratified analyses of pregnancy rates confirmed robustness of this primary outcome by showing similar results regardless of IVF or ICSI, or number of embryos transferred. A slightly higher follicular response with corifollitropin alfa resulted in a higher number of cumulus-oocyte-complexes compared with rFSH [estimated difference 1.2 (95% CI: 0.5; 1.9)], whereas median duration of stimulation was equal (9 days) and incidence of (moderate/severe) ovarian hyperstimulation syndrome was the same (4.1 and 2.7%, respectively P = 0.15).
                Corifollitropin alfa is a novel and effective treatment option for potential normal responder patients undergoing ovarian stimulation with GnRH antagonist co-treatment for IVF resulting in a high ongoing pregnancy rate, equal to that achieved with daily rFSH. The trial was registered under ClinicalTrials.gov identifier NTC00696800. In this double-blind, double-dummy, randomized, equivalence trial (Ensure), 396 women weighing 60kg or less who underwent controlled ovarian stimulation prior to IVF or intracytoplasmic sperm injection were randomized in a 2:1 ratio to a single dose of 100mug corifollitropin alfa or daily 150IU recombinant FSH (rFSH) for the first 7days of stimulation in a gonadotrophin-releasing hormone antagonist protocol. The mean +/- SD number of oocytes retrieved per started cycle was 13.3 +/- 7.3 for corifollitropin alfa versus 10.6 +/- 5.9 for rFSH. The estimated treatment difference of +2.5 oocytes (95% CI 1.2-3.9) in favour of corifollitropin alfa (P<0.001) was well within the predefined equivalence margin. The median (range) duration of stimulation was 9 (6-15) days in both groups. In 32.8% of the patients, one injection of corifollitropin alfa was sufficient to reach the human chorionic gonadotrophin criterion. The incidence of moderate and severe ovarian hyperstimulation syndrome was 3.4% for corifollitropin alfa and 1.6% for rFSH. A dose of 100mug corifollitropin alfa offers a simplified treatment option for potential normal responder patients with a lower body weight.
                2010 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.
The use of a medium dose of long-acting FSH is a safe treatment option and equally effective compared to daily FSH. Further research is needed to determine if long-acting FSH is safe and effective for use in hyper- or poor responders and in women with all causes of subfertility.