Comparative incidence of ovarian hyperstimulation syndrome following ovarian stimulation with corifollitropin alfa or recombinant FSH

Corifollitropin alfa is a novel recombinant gonadotrophin with sustained follicle-stimulating activity. A single injection can replace seven daily injections of recombinant follicle-stimulating hormone (rFSH) during the first week of ovarian stimulation. All cases of ovarian hyperstimulation syndrome (OHSS) with corifollitropin alfa intervention in a gonadotrophin-releasing hormone antagonist protocol have been assessed in three large trials: Engage, Ensure and Trust. Overall, 1705 patients received corifollitropin alfa and 5.6% experienced mild, moderate or severe OHSS. In the randomized controlled trials, Engage and Ensure, the pooled incidence of OHSS with corifollitropin alfa was 6.9% (71/1023 patients) compared with 6.0% (53/880 patients) in the rFSH group. Adjusted for trial, the odds ratio for OHSS was 1.18 (95% CI 0.81-1.71) indicating that the risk of OHSS for corifollitropin alfa was similar to that for rFSH. The incidence of mild, moderate and severe OHSS was 3.0%, 2.2% and 1.8%, respectively, with corifollitropin alfa, with 1.9% requiring hospitalization, and 3.5%, 1.3% and 1.3%, respectively, in the rFSH arms, with 0.9% requiring hospitalization. Despite a higher ovarian response with corifollitropin alfa compared with rFSH for the first 7 days of ovarian stimulation, the incidence of OHSS was similar. (C) 2012, Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.