Switching anti-TNF agent can benefit RA patients

The majority of rheumatoid arthritis (RA) patients who are unable to tolerate or fail to respond to an anti-tumor necrosis factor alpha (anti-TNF) agent will benefit from switching to a second agent.

Using the British Society for Rheumatology Biologics Register a prospective cohort of 6,739 patients starting a new anti-TNF treatment were followed for a mean period of 15 months. Of these, 876 subjects started adalimumab, 2,826 etanercept and 3,037 infliximab. During follow-up 841 patients stopped taking the initial anti-TNF agent because of a lack of efficacy and 1,023 stopped because of toxicity. Of those stopping these agents 503 switched to a second drug because of a lack of efficacy and 353 switched because of toxicity. Deborah Symmons and colleagues note that where first drug discontinuation was due to inefficacy this was associated with an increased rate of second drug discontinuation due to inefficacy (hazard ratio [HR] 2.7) but not toxicity (HR 1.1). Also, those who switched because of toxicity were 2.3 times more likely to discontinue the second drug because of continued toxicity, but there was no associated change in efficacy. The types of adverse event associated with the second drug were often different from those caused by the first. The group concludes “there is a strong case for switching patients to a second anti-TNF agent when failure to respond to a first agent occurs”. However, they call for further investigation to determine whether there is a role for a third agent or if it is better to move to a different class of biologic therapy. (Source: Arthritis & Rheumatism : March 2007.)