The Editorial Executive Committee welcomes letters, which should be less than 250 words. Before a decision to publish is made, letters which refer to a published article may be sent to the author for a response. Any letter may be sent to an expert for comment. When letters are published, they are usually accompanied in the same issue by their responses or comments. The Committee screens out discourteous, inaccurate or libellous statements. The letters are sub-edited before publication. Authors are required to declare any conflicts of interest. The Committee's decision on publication is final.

Letter to the Editor

Editor, – Since the article on tumour necrosis factor inhibitors was published (Aust Prescr 2006;29:67-70), further evidence has emerged about the risk of malignancy associated with these drugs. A meta-analysis of nine published randomised placebo-controlled clinical trials of adalimumab and infliximab in rheumatoid arthritis showed a 3.3-fold (95% CI* 1.2-9.1) increased risk of malignancy.1Patients with prior malignancy were excluded from these trials. Malignancies were significantly more common in those taking high doses compared to low doses of tumour necrosis factor inhibitors.

A US observational study of 6597 patients with rheumatoid arthritis treated with tumour necrosis factor inhibitors showed that their use was associated with an increased risk of non-melanotic skin cancer (odds ratio 1.5, 95% CI 1.2-1.8) and melanoma (odds ratio 2.3, 95% CI 0.9-5.4).2However, no other malignancy was associated and the overall risk of any cancer was 1.0 (95% CI 0.8-1.2).

There is no current evidence for the safety of tumour necrosis factor inhibitors in patients with a history of malignancy. Hence, both the UK guidelines and the current product information for these products recommend that tumour necrosis factor inhibitors should be used with caution in patients with previous malignancy.3We suggest that until more long-term safety data are available, patients with recent malignancy should not be required to 'fail' a tumour necrosis factor inhibitor before being eligible for an alternative biological disease-modifying antirheumatic drug therapy under the Pharmaceutical Benefits Scheme.

* CI = confidence interval

Catherine L Hill
Staff Specialist, Rheumatology Unit
The Queen Elizabeth Hospital
Adelaide

Peter Nash
Director, Rheumatology Research Unit
Sunshine Coast
Associate Professor
Department of Medicine
University of Queensland

References

  1. Bongartz T, Sutton AJ, Sweeting MJ, Buchan I, Matteson EL, Montori V. Anti-TNF antibody therapy in rheumatoid arthritis and the risk of serious infections and malignancies: systematic review and meta-analysis of rare harmful effects in randomized controlled trials. JAMA 2006;295:2275-85.
  2. Wolfe F, Michaud K. Biologic treatment of rheumatoid arthritis and the risk of malignancy: analyses from a large US observational study. Arthritis Rheum 2007;56:2886-95.
  3. Ledingham J, Deighton C; British Society for Rheumatology Standards, Guidelines and Audit Working Group. Update on the British Society for Rheumatology guidelines for prescribing TNF alpha blockers in adults with rheumatoid arthritis (update of previous guidelines of April 2001). Rheumatology 2005;44:157-63.