Schering-Plough Corp today announced results from the phase III ENGAGE clinical trial demonstrating that a single injection of corifollitropin alfa, first in the class of sustained follicle stimulants, achieved similar efficacy to recombinant follicle stimulating hormone (rFSH) given once daily for seven days.
The ENGAGE data was presented along with data from the phase III ENSURE trial and the phase II REALIZE trial at the 25th annual meeting of the European Society of Human Reproduction and Embryology (ESHRE) in Amsterdam, The Netherlands. “The burden of fertility treatment is a major challenge for women experiencing difficulty conceiving,” said Thomas Koestler, executive vice president and president, Schering-Plough Research Institute.
“Schering-Plough is committed to making fertility treatments easier, and these results demonstrate that corifollitropin alfa in combination with a GnRH antagonist may be an effective treatment that can reduce the number of injections and the length of treatment protocols.”
ENGAGE is the largest double-blind fertility agent trial ever performed. The ongoing pregnancy rate, the primary endpoint of the ENGAGE non-inferiority trial, obtained in the 150 mcg corifollitropin alfa treatment arm (38.9 percent per started cycle) was similar to that achieved in patients receiving a daily dose of 200 IU rFSH (follitropin beta) for seven days (38.1 percent per started cycle).
ENGAGE also demonstrated that a single injection of 150 mcg corifollitropin alfa achieved similar oocyte and embryo quality compared to a daily dose of 200 IU rFSH given for one week. Further sub-analyses of the ENGAGE trial showed a single injection of 150 mcg corifollitropin alfa, compared to the daily rFSH treatment arm, achieved consistently high pregnancy outcomes regardless of fertilization procedure (in-vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI), number of embryos transferred (single or double), or day of embryo transfer (day three or five), confirming the robustness of the main efficacy outcome.
An additional sub-analysis of the ENGAGE data demonstrated that endogenous luteinizing hormone (LH) levels do not affect ongoing pregnancy rates in women undergoing controlled ovarian stimulation (COS) with a standardized rFSH / gonadotropin-releasing hormone (GnRH) antagonist protocol.
An analysis compared data from the ENGAGE trial to data from the ENSURE trial. The ENSURE trial used a similar protocol to ENGAGE with identical patient inclusion criteria but different body weight categories. It showed that exposure and ovarian response were similar after a single-dose of 100 mcg corifollitropin alfa in patients weighing 60 kg or less, as compared to 150 mcg corifollitropin alfa in patients weighing more than 60 kg.
Additional data from the ENSURE trial show that in patients weighing 60 kg or less, a single dose of 100 mcg corifollitropin alfa resulted in significantly more oocytes and an equally short duration of treatment as those receiving 150 IU rFSH daily during the first week of stimulation.
Data was also presented from the phase II REALIZE study, a 50 patient, open-label uncontrolled pilot study. In this study, a single dose of 100 mcg or 150 mcg corifollitropin alfa in a long GnRH agonist protocol was able to support multifollicular development during the first week of ovarian stimulation.