When Enbrel (etanercept), the first biologic therapy for rheumatoid arthritis became available in 1998, it was said that it could slow disease progression. Remicade (infliximab), Humira (adalimumab), Rituxan (rituximab), and Orencia (abatacept) followed. Has it been proven that these drugs prevent joint damage and deformity? Will a person with early rheumatoid arthritis who starts on a biologic drug not experience joint deformities?
The Effect of Biologics on Joint Damage
It has been recognized that the traditional disease modifying drugs, also referred to as DMARDs (e.g. methotrexate, Plaquenil, Azulfidine and Arava), may improve both clinical symptoms and slow joint damage. Data has shown that the biological DMARDs - Enbrel, Humira, Remicade, Rituxan and Orencia - may do likewise, but the three TNF blockers - Enbrel, Remicade, and Humira - appear to be most effective.
While methotrexate was similar to all three drugs in clinical efficacy, those patients on TNF blockers had a better chance of halting joint damage progression, which is measured using x-rays and is known as "x-ray progression." This benefit was enhanced with the addition of methotrexate in combination with the TNF blockers.
The Significance of X-Ray Evidence
Joint damage visible on x-rays correlates directly with joint deformity and disability. Halting x-ray progression is an important part of treating rheumatoid arthritis. It also is important to note that joint damage visible on x-rays often occurs in the first two years of disease, so early diagnosis and treatment with disease modifying drugs is essential in improving the long-term outcome in patients that have moderate to severe rheumatoid arthritis. Despite the superiority of TNF blockers in preventing joint damage, up to 25 percent of patients on methotrexate alone can still achieve clinical remission.
Answer provided by Scott J. Zashin, M.D., clinical assistant professor at University of Texas Southwestern Medical School, Division of Rheumatology, in Dallas, Texas. Dr. Zashin is also an attending physician at Presbyterian Hospitals of Dallas and Plano. He is a fellow of the American College of Physicians and the American College of Rheumatology and a member of the American Medical Association. Dr. Zashin is author of Arthritis Without Pain - The Miracle Of TNF Blockers. The book is useful for anyone on one of the biologic drugs (Enbrel, Remicade, Humira) or considering the biologic drugs. Read my review of the book.
