Rheumatoid arthritis (RA) is an autoimmune disease that causes pain and oedema in the joint area, hardness of the joint and eventual loss of joint function.
There are 1.5 million rheumatoid arthritis patients in the United States, which accounts for 0.6% of adults in the US [Helmick et al, Arthritis Rheum 58 (2008) 15]. In 2010, seven major countries (US, Japan, UK, Germany, Spain, Italy, France) had an estimated 4.6 million RA patients.
Currently there are no drugs that can cure rheumatoid arthritis, with drugs used to instead provide pain relieve, reduce oedema and slow the progression of the disease. Although antibody drugs for rheumatoid arthritis patients are under development, the cost of treatment is expected to be extreme.