Guidelines for the use of biologics
We read with interest the most recent consensus statement on the use of biological agents in rheumatoid arthritis, stating that improvement should be achieved by 12 weeks of therapy . The most recent guidelines issued this year in the UK by the National Institute for Health and Clinical Excellence (NICE) state that anti-TNF agents should only be discontinued if an adequate response (defined as a DAS28 reduction of <1.2) is not obtained after 6 months of therapy . This replaced earlier NICE guidelines which stated that treatment should be withdrawn ifa response was not obtained at 3 months of therapy . The British Society for Rheumatology (BSR) have questioned whether 3 or even 6 months is long enough for an adequate therapeutic trial .
The randomised controlled trials on which anti-TNF guidelines are based reported in most instances only cumulative responses at 3 and 6 months, and due to the attrition rate seen on anti-TNF agents for reasons such as adverse events, may underestimate the number of patients whose first response was between 3 and 6 months. Our own data has shown that a substantial proportion (55%) of rheumatoid arthritis patients who fail to meet NICE criteria for a response at 3 months go on to achieve a response by 6 months . This would suggest that an extension of the trial period to 6 months rather than 12 weeks would benefit a significant number of patients whose disease does not show a response to anti-TNF in the first 3 months of therapy, supporting such a change in the guidelines.
 Furst DE, Breedveld FC, Kalden JR et al. Updated consensus statement on biological agents for the treatment of rheumatic diseases, 2007. Ann Rheum Dis 2007;66 Suppl 3:iii2–22.
 National Institute of Clinical Excellence. Adalimumab, etanerceptand infliximab for the treatment of rheumatoid arthritis. October 2007. http://www.nice.org.uk/nicemedia/pdf/TA130guidance.pdf.
 National Institute of Clinical Excellence. Guidance on the use of etanercept and infliximab for the treatment of rheumatoid arthritis. March 2002. http://www.nice.org.uk/pdf/RA-PDF.pdf
 Ledingham J, Deighton C. Update on the British Society for Rheumatology guidelines for prescribing TNFa blockers in adults with rheumatoid arthritis (update of previous guidelines of April 2001). Rheumatology 2005;44:157–63.
 Pocock JM, Östör AJK. Assessment of anti-TNF efficacy in rheumatoid arthritis – Is three months sufficient? [abstract 143] BSR 2007.