Certolizumab is reduced in Crohn's disease relative to the efficacy observed with adalimumab [24, 25], which suggests that Fc-mediated effector functions may be important. Binding of mAbs to FcRn affects clearance, so a similarity assessment of biosimilars should also include sensitive methods to assess binding to FcRn. ABP 501 was shown to have similar binding to FcRn as compared with adalimumab.
Assessment of the bioactivity of adalimumab should include assessment of multiple in vitro endpoints (NFjB-dependent and NFjB-independent) and should include binding to both soluble and transmembrane TNFa. ABP 501 has been shown to be similar to adalimumab in its ability to neutralize TNFa-induced caspase activation, chemokine production, and cytotoxicity, functions inclusive of both NFjB-dependen