Recombinant human follicle-stimulating hormone (rhFSH) is a commonly used treatment for female infertility, but its short half-life requires multiple doses. Even corifollitropin alfa, which has a longer half-life, still requires additional injections of rhFSH after 7 days. Our goal was to use anti-serum albumin Fab-associated (SAFA) technology to develop a long-acting FSH that eliminates the need for additional injections.
SAFA-FSH was produced using a Chinese hamster ovary expression system, and its biological activity was confirmed through tests measuring its ability to stimulate cAMP production, estradiol synthesis, and the expression of FSH receptor, hCYP19α1, and hSTAR in KGN cells. The effects of SAFA-FSH and rhTSH on ovarian weight gain and serum estradiol levels were compared in SD rats.
The results showed that SAFA-FSH stimulates cAMP synthesis in KGN cells and increases the expression of FSH receptor, hCYP19α1, and hSTAR with increasing concentrations of SAFA-FSH. Female SD rats aged 21 days, receiving daily subcutaneous hCG injections for 5 days, showed a significant increase in ovarian weight with SAFA-FSH administered on the first day or with 9 injections of rhFSH over 5 days. Notably, the group receiving SAFA-FSH on the first and third day showed an even greater increase in ovarian weight. In addition, the SAFA-FSH group showed a significant increase in estradiol levels, while the rhFSH group did not.
These findings suggest that SAFA-FSH could be a viable alternative to current rhFSH treatments for female infertility. However, further research is needed to fully evaluate its safety and effectiveness in clinical settings.