Anti-TNF drugs eases rheumatoid arthritis pain
Dr. Anthony Komaroff www.AskDoctorK.com October 30, 2012 5:02PM
Copyright 2002 President and Fellows of Harvard College on behalf of HMS Media Services, Photo by Liza Green, HMS Media Services, Anthony Leader Komaroff, MD, Harvard Health Publications
Updated: December 1, 2012 6:12AM
Dear Doctor K: I have rheumatoid arthritis and take anti-TNF drugs. I’d like to understand how they work.
Dear Reader: Rheumatoid arthritis (RA) is a chronic autoimmune disease in which the body’s immune system mistakenly attacks healthy tissue in the joints.
When the immune system attacks anything — a foreign germ or the body’s own tissue — it acts like an army. There are immune system cells that are like the generals: They direct the troops. They do so by sending chemical signals that tell other cells to attack or to stop attacking.
One of these chemical signals is a molecule called tumor necrosis factor, or TNF. It’s one of the “attack” signals. TNF binds to normal joint tissues and increases inflammation. Anti-TNF drugs bind to the receptor sites on the joint tissue cells, blocking the TNF from causing destructive inflammation.
In rheumatoid arthritis, the inflammation begins in the synovium, a thin membrane that lines the joints. There, something triggers an inflammatory reaction. As a result, joint cells produce harmful substances that attack the joints themselves. Synovial cells also proliferate, forming a rough, grainy tissue that grows into the joint cavity and eats away at cartilage.
These changes cause a number of uncomfortable symptoms:
Constant or recurring pain or tenderness in joints
Stiffness and difficulty using or moving joints normally
Swelling in and around joints
Warmth and redness in joints
Weight loss
Low-grade fever
Fatigue
Prolonged morning stiffness
The goals in treating RA are to prevent or control joint damage, prevent loss of function and reduce pain. To prevent permanent damage, the disease is often treated aggressively from the start.
Anti-TNF agents can dramatically improve the symptoms of rheumatoid arthritis and slow the progressive damage to the joints that often occurs.
Five anti-TNF agents are now available:
adalimumab (Humira)
certolizumab (Cimzia)
etanercept (Enbrel)
infliximab (Remicade)
golimumab (Simponi)
Anti-TNF drugs are potent and expensive, and they can have serious side effects. But they appear to do what other drugs have failed to do: stop the rate of joint deterioration.
Write to Dr. Komaroff at www.AskDoctorK.com
