The 'totality-of-the-evidence' biosimilarity concept requires that sufficient structural, functional, nonclinical, and clinical data are acquired in a stepwise manner, to demonstrate that no clinically meaningful differences in quality, safety, or efficacy are observed compared with the reference product. We describe the totality of the evidence for PF-06438179/GP1111 (PF-SZ-IFX; IXIFI™ [infliximab-qbtx]/Zessly®) that supported its approval as an infliximab (IFX) biosimilar for all eligible indications of reference IFX (ref-IFX; Remicade®) in Europe and in the US. Analytical similarity involving 