Rheumatoid arthritis is a common chronic inflammatory and destructive arthropathy that cannot be cured and that has substantial personal, social, and economic costs. The long-term prognosis is poor: 80 percent of affected patients are disabled after 20 years,¹ and life expectancy is reduced by an average of 3 to 18 years.² The medical cost of rheumatoid arthritis averages $5,919 per case per year in the United States³ and approximately £2,600 per case per year in the United Kingdom.⁴ Current slow-acting antirheumatic drugs have limited efficacy and many side effects. Moreover, they do not improve the long-term prognosis of rheumatoid arthritis. . . .