Background Anti-TNF medications are frequently used to treat autoimmune inflammatory conditions. They are of proven benefit, but are associated with significant side effects and expense which could be reduced by reducing the anti-TNF frequency.
Objectives To monitor if decreased frequency of anti-TNF can provide adequate disease control.
Methods From 2009, patients on anti-TNF with a Disease activity score suggesting remission for at least 12 months, who wanted to reduce their anti-TNF, had the frequency of injections reduced. They were advised this may be associated with a flare of their disease and that equivalent disease control could not be guaranteed. Etanercept was reduced to every 10 days and adalimumab to every 3 weeks. Patients were asked to contact the Unit urgently if they thought their disease was flaring.
Results 15 patients (9 male, 6 female) reduced their anti-TNF frequency: 4 ankylosing spondylitis (AS), 5 rheumatoid arthritis (RA), 6 psoriatic arthritis (PA) and 1 SAPHO syndrome.10 were on Etanercept, 5 on Adalimumab. Median length of time from disease control to reduction was 24 months.11/15 patients have been maintained on reduced anti-TNF frequency. 6 patients developed increased symptoms. However, all improved on increasing the injection frequency, with 2 switching back to reduced dose successfully. 2 patients (1 PA, I RA) asked to reduce the frequency of injections further and remain well on this dose. One patient with SAPHO syndrome is in remission on monthly adalimumab and requested further reduction to every 5 weeks in January 2015.
Conclusions Our results demonstrate that anti-TNF remains effective at a reduced dosage interval. Although some patients felt worse, their symptoms improved on increasing the anti-TNF frequency. None of the patients had a severe relapse necessitating steroids or a treatment change. These findings add to those in the literature, which suggest reducing anti-TNF frequency could be as effective, but less costly in AS  and RA, if low disease activity is confirmed .
This was a self-selecting group, and only patients requesting less frequent injections were included. However, our results suggest that patients with a prolonged and good response to anti-TNF could be considered for dose reduction. This may be associated with a reduction in potential side effects such as infection and there are significant cost implications. For example, one patient receiving Adalimumab every 3 weeks instead of every 2 weeks would save £2987.84 per annum.
The potential benefits of anti-TNF dosage reduction have to be balanced against the increased risk of disease flares and progression. Further, larger studies, of the health and economic consequences are required. However, this study shows, at least in principal that patients with inflammatory conditions, requiring anti-TNF medications, may be able to have their disease adequately controlled on less frequent administration.
Jakub Závada et al.A tailored approach to reduce dose of anti-TNF drugs may be equally effective, but substantially less costly than standard dosing in patients with ankylosing spondylitis over 1 year: a propensity score-matched cohort study. Ann Rheum Dis 2014.
Marks D et al.Does combined clinical and ultrasound assessment allow selection of individuals with rheumatoid arthritis for sustained reduction of anti-TNF therapy? Arthritis Care Res 2015 Jan 20.
Disclosure of Interest None declared