Why Do the Majority of Submissions for Bridging from a Prefilled Syringe to an Autoinjector Include Bioequivalence Studies in Order to Demonstrate Comparability?

Abstract

A recent paper reviewed clinical studies intending to bridge a prefilled syringe (PFS) to an autoinjector (AI) based on regulatory submission packages sent to the FDA. An AI generally uses the identical PFS within the AI and the AI typically results in a more consistent injection than can be achieved with a PFS. It is noted that several studies submitted to the FDA did not demonstrate bioequivalence (BE) between the PFS and AI, yet the products were approved anyway. The author of this Commentary believes that formal BE studies should not be required for such bridging studies.

Keywords: autoinjector; bioequivalence; comparability; pharmacokinetics; prefilled syringe.