An aqueous formulation of recombinant human FSH is more efficient than a freeze-dried cake formulation in clomiphene-resistant women with chronic anovulation

This open-label, randomized, multicenter study, conducted at nine sites in the United States, compared the efficacy, safety, and local tolerability of a new aqueous formulation of recombinant follicle-stimulating hormone (Organon USA Inc.) with that of a freeze-dried cake formulation. A total of 126 clomiphene-resistant anovulatory women (World Health Organization [WHO] Group II) were randomized to one of two treatment groups, with 62 receiving the aqueous formulation and 64 receiving the cake formulation. One cycle of ovulation induction with recombinant follicle-stimulating hormone (rFSH) was administered subcutaneously as an aqueous or cake formulation, followed by human chorionic gonadotropin. Main outcome measures were ovulation and ongoing pregnancy rates and amount and duration of exposure to rFSH. Ovulation rates after one cycle of ovulation induction were similar for the aqueous (90%) and cake (83%) formulations. Ongoing pregnancy rates were also similar for the two groups (18% and 17%, respectively). The mean total amount of rFSH given to subjects was significantly lower (p=0.006) in the aqueous (818 IU) than in the cake group (1,200 IU). Mean duration of rFSH treatment was also significantly shorter (p=0.0003) in the aqueous group compared with the cake group (9.1 vs. 12.0 days). Local reactions were similar with both formulations, except for swelling, which was significantly less frequent in the aqueous group. Compared with the cake formulation, significantly less aqueous formulation was required for a significantly shorter duration to produce the same ongoing pregnancy rate.