Chronic inflammatory diseases (CID), including inflammatory bowel diseases (IBD) (of which Crohn's disease [CD] and ulcerative colitis [UC] are the two most prevailed entities), rheumatic conditions (rheumatoid arthritis [RA], axial spondyloarthropathy [axSpA], psoriatic arthritis [PsA]), skin diseases (psoriasis [PsO], hidradenitis suppurativa [HS]), and eye disease (non-infectious uveitis [NiU]), are diseases of the immune system that are managed with biological agents targeting the pro-inflammatory cytokine tumour necrosis factor-α (TNF), i.e. TNF inhibitors.