What is the problem and what is known about it so far?

Rheumatoid arthritis (RA) is a chronic disease in which inflammation leads to painful, swollen, and deformed joints. It usually affects the small joints of the hands and feet but may develop in any joint. People with RA usually have flares of joint pain and stiffness that last for weeks or months. Between flares, people with RA can be relatively free of symptoms. There is no cure for RA. Repeated attacks eventually destroy joints, and about 1 in 10 people with RA becomes severely disabled from joint destruction. Treatment ...