Comparative assessment of the consistency and quality of a highly purified FSH extracted from human urine (urofollitropin) and a recombinant human FSH (follitropin alpha).

The revolutionary development of biotechnology-derived therapeutic proteins has provided the expected improvements in quality, purity and consistency, as demonstrated in recombinant human FSH (rhFSH). However, the development of urine-derived gonadotrophins has not always shown comparable improvements. More recently, highly purified urine-derived FSH (uFSH-HP) products have become widely available. The relative purity, level of urine-derived contaminants, and consistency of one such highly purified human uFSH (uhFSH) (urofollitropin) has been assessed and directly compared with rhFSH (follitropin alpha). It has been demonstrated that the highly purified urofollitropin contains variable levels of urine-derived contaminant proteins and demonstrates a variable level of FSH purity, FSH isoforms, and delivered dose. These variable factors may contribute to the control of ovarian stimulation. The relative purity, variable consistency and the presence of contaminants indicates that the urofollitropin is, at best, a partially purified uFSH that is not able to meet the quality attributes of follitropin alpha (rhFSH).