Abstract
Exogenous human follicle-stimulating hormone (hFSH), either derived from extraction and purification from the urine or obtained by recombinant technology in the form of follitropin α, β and δ (rFSH), has been used for decades in the treatment of infertility. The main applications of FSH treatment in the woman have been, and still are, ovulation induction in oligo-anovulatory subjects, and stimulation of the development of a cohort of follicles in patients undergoing controlled ovarian stimulation (COS) for in vitro fertilization (IVF). In the last years, two biosimilars of follitropin alfa, rFSH compounds structurally and functionally similar to the originator, have been approved and marketed for clinical use in Europe. Moreover, some other rFSH biosimilars are currently under investigation. The objective of this article is to review the available evidences comparing the efficacy, safety, and cost-effectiveness of rFSH follitropin alpha originator with its biosimilars, discussing the clinical trials that allowed biosimilars to get registration and marketing authorization.