Rituximab is a safe and effective treatment for rheumatoid arthritis

This study examined the use of rituximab in clinical practice for patients with rheumatoid arthritis. 

Rheumatoid arthritis in an autoimmune disorder, meaning the immune system, which normally fights off invaders such as bacteria, begins to attack healthy body tissue. A mainstay of treatment is immunosuppressants, or drugs to block the immune response. Rituximab (Rituxan) is an anti-CP20 monocolonal antibody, which inhibits the inflammation caused by B cells, part of the immune system. Rituximab is often used in combination with methotrexate (Trexall) for active, severe rheumatoid arthritis in patients who have not responded to other treatments.

Rituximab has been proven in clinical trials to be safe and effective, and has the added benefit of having long periods of time between treatment courses (approximately 6 months), rather than the monthly or more frequent treatments for other therapies. Clinical trials have now shown the long-term safety of rituximab, as patients have been followed for over 10 years, and for more than 17 courses of treatment. However, use of a drug in a clinical trial can be different from actual use in clinic patients, as in clinical practice the drug is available to a wider range of patients. This observational study evaluated the safety and efficacy of rituximab in routine care for rheumatoid arthritis.

In this prospective, observational study, 2,484 patients were treated with several courses of rituximab (22.7% as a single therapy) and followed for up to 2 years following each treatment course. Patients were evaluated with the Disease Activity Score in 28 Joints, a measure of the number and severity of disease in involved joints, and the Health Assessment Questionnaire-Disability Index. The average retreatment interval (the time between treatment and further treatment) was 9.6 months between courses 1 and 2, and 7.7 months between courses 5 and 6.

Average scores on the Disease Activity Score in 28 Joints were decreased by 1.4 points by 4 months post-treatment, and another 1.4 points by 8 months post-treatment, indicating decreased disease activity. As patients underwent further treatment courses of rituximab, the Disease Activity Score in 28 Joints scores continued to decrease. 3.5% of patients had low disease activity at the start of the study, 23.7% after course 1, 30.8% after course 2 and 42.4% after course 3. Remission (a time of disease inactivity, and the goal of rheumatoid arthritis treatment) increased from 9.8% at the end of course 1 to 29.5% at the end of course 3.

Physician-reported average swollen joint count decreased from 7.9 at the beginning of the study to 4.1 at month 8 of course 1. Tender joint count decreased from 11 at the beginning of the study to 6.1 at month 8 of course 1 and 4.3 at month 8 of course 3.

By the eighth month following treatment course 1, 75% of physicians and 71.5% of patients thought rituximab was effective, and 98.6% of physicians and 92.7% of patients found it to be safe and tolerable. Adverse effects were seen in 21.4% of patients, and included infection (1.8%), parasitic disease (9.1%), and skin conditions (5.5%).

This study concluded that rituximab was a safe and effective treatment for rheumatoid arthritis in clinical practice.