Comparing a biosimilar follitropin alfa (Cinnal-f (R)) with Gonal-f (R) in women undergoing ovarian stimulation: An RCT

Background: Advances in recombinant DNA technology led to the development of recombinant follitropin alfa. Recombinant human follicle-stimulating hormone products are used to stimulate follicular maturation. Objective: To compare the efficacy and safety of a biosimilar-candidate recombinant human follicle-stimulating hormone (Cinnal-f (R); CinnaGen, Iran) with the reference product (Gonal-f (R); Merck Serono, Germany) in women undergoing ovarian stimulation for intracytoplasmic sperm injection (ICSI). Materials and Methods: In this randomized controlled trial, a total sample size of 200 women (age < 35 yr, candidate for ICSI) was calculated. Participants began a pituitary downregulation protocol with buserelin. They received 150 IU daily of either Cinnal-f (R) or Gonal-f (R) from the second day of their cycle. The primary outcome of the study was the percentage of metaphase II (MII) oocytes. The secondary outcomes included the number and quality of oocytes retrieved, duration of stimulation, fertilization rate, embryo quality, the number of clinical and ongoing pregnancies, and the incidence of ovarian hyperstimulation syndrome (as an important safety marker). Results: A total of 208 women were enrolled, of whom, 200 completed the study period. Ovarian stimulation with Cinnal-f (R) resulted in a comparable percentage of MII oocytes as with Gonal-f (R) (78.64% vs 80.02%, respectively; p = 0.81). No statistically significant difference was seen in the secondary outcomes between the groups. Conclusion: Cinnal-f (R) proved non-inferior to Gonal-f (R), based on the percentage of MII oocytes in women aged < 35 yr undergoing ICSI. Our findings confirm that the efficacy and safety profiles of Cinnal-f (R) and Gonal-f (R) are similar.