A new model to predict effectiveness of infliximab (Remicade) in rheumatoid arthritis patients

This study investigated whether doctors could predict the long term effectiveness of infliximab (Remicade) treatment for rheumatoid arthritis, based on early results at 3 months. 

Rheumatoid arthritis is an autoimmune disease, caused by the immune system attacking healthy tissue. Blocking the immune system with disease-modifying antirheumatic drugs (DMARDs) such as methotrexate (Rheumatrex and Trexall) can slow the progression of rheumatoid arthritis. If DMARD treatment is unsuccessful, patients may try TNF inhibitor drugs such as infliximab (Remicade), which block the activity of tumor-necrosis factor, a protein that causes inflammation.

The times when a disease is active are known as flares, and times when the symptoms have reduced are known as remission. Disease activity in terms of flares and remissions can vary among patients, and it is difficult to predict who will respond to drug treatment. 

This study involved 307 patients who were previously unresponsive to methotrexate. Each patient received the standard dose of infliximab (3 mg/kg) at weeks 0, 2 and 6, followed by 3 mg/kg, 6 mg/kg, or 10 mg/kg every 8 weeks from Week 14 to Week 46. Disease activity was compared at Week 14 and Week 54.

The authors found that disease activity levels at Week 14 were a good predictor of future disease levels at Week 54. For example, in patients with low disease activity who had not reached remission by Week 14, 50% would not reach remission by Week 54, even after 1 year of 3 mg/kg infliximab treatment. In patients with medium disease activity at Week 14, an increase in infliximab dose to 6 or 10 mg/kg led to remission in more than half of the patients.

The authors conclude that making an early decision to increase the dose of infliximab at Week 14 may lead to better chances of remission in certain patients after 1 year. 

Patients in the study had “high disease activity” before they started infliximab treatment. It is unclear if patients with low or extremely high disease activity would also benefit from this prediction model.

If you have concerns about infliximab treatment, please discuss them with your doctor.