Table 3.
Differences between ETN and IFX
| Difference in mode of action | ETN | IFX |
|---|---|---|
| MTX effects on pharmacokinetics [25] | None | Increase in serum concentration |
| Specificity [26] | TNF alpha/LT alpha | TNF alpha |
| Transmembrane TNF binding/neutralization [26] | ++ | +++ |
| Half-life, days [25] | 4.8 | 9.5 |
| In vitro complement activation [25] | No | Yes |
| Structure [26] |
Hu sTNFR2-Fcγl |
Mo/Hu chimeric IgGκ |
| Neutralizing antibody [24] | No | Yes |
| Reverse signaling [26] | ||
| Apoptosis [26] | ± | +++ |
| Cytokine suppression [26] | ± | +++ |
| Peak-trough ratios [26] | Low | High |
± very weak; ++ moderate; +++ strong
ETN etanercept; Fc fusion; Hu human; IFX infliximab; IgG immunoglobulin G; LT lymphotoxin; Mo murine; MTX methotrexate; TNF tumor necrosis factor; sTNFR2 soluble TNF receptor 2