TNF inhibitors are being increasingly used in the treatment of various immune-mediated diseases such as rheumatoid arthritis, ankylosing spondylitis, inflammatory bowel diseases, and psoriasis.
There are five tumor necrosis factor inhibitors available to treat rheumatoid arthritis and other immune-mediated diseases worldwide. Biosimilar versions of TNF inhibitors are now available in certain countries. Additional biosimilar agents are currently in development.
TNF inhibitors are safer than conventional DMARDs (disease-modifying anti-rheumatic drugs) and equally effective when used as monotherapy. In combination with methotrexate, they are superior to conventional DMARDs.
An Overview of The Five TNF Inhibitors:
Etanercept (Enbrel):
- This soluble TNF receptor fusion protein consists of two TNF receptors attached to the Fc section of immunoglobulin G. The medication is bivalent, meaning that one etanercept molecule binds to two TNF molecules. Subcutaneous injections of Etanercept are administered once weekly or twice weekly.
- Etanercept can be used to treat a variety of conditions including ankylosing spondylitis, rheumatoid arthritis, juvenile idiopathic arthritis, and psoriatic arthritis. However, etanercept does not work for Crohn’s disease and ulcerative colitis. Some studies have associated a flare-up in the symptoms of IBDs when initiated on etanercept therapy.
Read: Simponi vs Enbrel (Golimumab Vs Etanercept)
Infliximab (Remicade):
- TNF-specific chimeric monoclonal antibodies (mAbs) are directed against TNF. The drug is chimeric because it contains both murine components and human ones. Infliximab’s antigen-binding section contains the kappa and heavy chains variable regions (VK) domains. The constant Fc domain is human. Once a steady-state is achieved, infliximab can be administered intravenously every six weeks.
- Infliximab can be used to treat rheumatoid arthritis, ankylosing spondylitis, psoriatic arthritis, Crohn’s disease, and ulcerative colitis.
- Infliximab-dyyb and infliximab have been approved in many countries around the world. They also carry all the indications that the legacy (originator compound) compound has.
Adalimumab (Humira):
- This recombinant fully-human mAb is administered subcutaneously instead of intravenously. It is recommended that you administer the drug every two weeks. Adalimumab has a lower chance of anti-drug antibodies formation than other drugs. It may be due to its humanized design. However, there are anti-drug antibody reactions to adalimumab. They can be neutralizing and directed against the idiotype.
- Adalimumab is approved for use in Crohn’s disease and plaque psoriasis. It can also be used to treat Crohn’s disease in children.
Read: Simponi vs Humira (Golimumab Vs Adalimumab)
Certolizumab (Cimzia):
- Certolizumab pegol is a humanized anti-TNF-alpha antibody fragment Fab’ that is chemically linked with polyethylene glycol. This medication neutralizes membrane-associated TNF-alpha. Subcutaneous injections of Certolizumab pegol are administered every two weeks. Some patients may require maintenance therapy at four-week intervals.
- Certolizumab pegol has been approved for use in Crohn’s disease and rheumatoid arthritis. It can also be used in psoriatic and ankylosing arthritis. It can also be used in uveitis or ulcerative colitis.
- The European Medicines Agency (EMA), has also approved a label modification for certolizumab pegol. This makes it the first TNF inhibitor that can be used in women with chronic rheumatic diseases during pregnancy and breastfeeding.
Golimumab:
- Golimumab is a mAb specific for TNF-alpha in humans and has a specific human IgG1 kappa. Golimumab can bind to both the transmembrane and soluble bioactive forms of human TNF-alpha. Subcutaneous injection is the best way to administer it.
- It is used to treat patients suffering from rheumatoid arthritis, psoriatic arthritis, and Ankylosing Spondylitis.