Overlapping biosimilar and originator follitropin alfa preparations: How much closer can they get?

Unfounded skepticism relating to biosimilars, arising from the assertion that they are not molecularly identical to their original counterpart, fails to acknowledge that no biological medicine, including Gonal-f (R) (from Merck Serono) is identical to itself. Molecular differences between the biosimilar and the reference medicines are irrelevant and clinically undetectable as long as they are contained within the accepted variability for the original medicine. Accordingly, the minor differences in 'ongoing pregnancy rate' and 'live birth' rate reported in a recent meta-analysis of biosimilars of Gonal-f (R) from Chua et al. are probably driven by product-unrelated factors, notwithstanding the fact that of the four Plc) can unambiguously be considered to be biosimilars. The EU Biosimilars model has proven successful, but some healthcare professionals, building on highly arguable premises, voice a distrust in biosimilars. Only if such scientifically unfounded distrust is reverted, the full promise of rFSH alfa biosimilars for reproductive medicine patients is likely to be fulfilled.

Automated summary

Unfounded skepticism regarding biosimilars is based on the assertion that they are not molecularly identical to their original counterpart. However, as long as the molecular differences between the biosimilars and the reference medicines fall within the accepted variability, they are clinically irrelevant and undetectable. The minor differences reported in a recent meta-analysis of Gonal-f (R) biosimilars are likely driven by factors unrelated to the products.