Background We have previously described a strategy for Tumour Necrosis Factor inhibitor (TNFi) dose reduction (TDR) for patients with rheumatoid arthritis (RA) that selects patients with “deep remission” using combined clinical and ultrasound (US).
Objectives The aim of this study was to assess the consequences of this TDR strategy  on the HAQ, DAS28-CRP and Area Under the Curve of CRP (AUCCRP) after follow-up (mean 28 months).
Methods A longitudinal observational study was performed. Patients with RA (ACR-EULAR 2010), on TNFi for >1 year, not taking oral corticosteroids, DAS28 ≤2.6 for >6 months and absent power Doppler synovitis on US underwent TDR by one third. Patients failing TDR (clinically/on US) were re-escalated to full dose. Patients were divided into 3 groups: Non-reducers (group A), sustained dose reducers (group B) and failed dose reducers (group C). We investigated the initial (TNFi start date) and the last HAQ, DAS28 and AUCCRP, as well as before and after TDR.
Results 152 patients with RA receiving TNFi were included. Between Oct 2011 & May 2015, 67 (44%) underwent TDR. 3 patients were lost to follow-up. Dose reducers have been followed-up for a mean 30.5 months after TDR. A total of 29 (45%) failed the TDR after a mean (SD) of 9.5 (7.9) months. By a mean (SD) of 22.4 (11.6) months following dose re-escalation, 27 (93%) continued to receive their TNFi, while 2 (7%) had switched to a different biologic.
Baseline characteristics of all groups were similar. However, we found that the initial HAQ score on starting TNFi was significantly higher for group A compared to groups B and C (mean 1.59 versus 0.95 and 1.28, respectively, p<0.05) and was higher for group C compared to group B (p=0.05).
When compared before and after reduction, both groups B and C showed a similar pattern of functional capacity and AUCCRP. Nevertheless, group B had lower last DAS28 (p<0.05). While analysing the most recent DAS28 of group C following dose re-escalation, 32% had achieved DAS28 remission, 20% developed lower (LDA), 44% moderate (MDA) and 4% severe disease activity (SDA).
Finally, we assessed the changes over time of DAS28 and HAQ scores. Group B had a higher DAS28 reduction then groups A and C (mean 3.6 vs. 2.43 and 2.75, respectively) (p<0.05), who both had similar changes. Nonetheless, HAQ score changed similarly between all patients.
Conclusions RA patients who fail dose reduction appear to have a higher DAS28 than those who were successful despite reintroduction of a standard dose of TNFi. However, in the majority of cases the level of DAS28 was <3.2 (LDA or better). Failed dose reduction did not appear to cause loss of functional capacity (HAQ) or a greater cumulative exposure to inflammation (AUCCRP) compared to successful reduction. The functional capacity (HAQ) at TNFi initiation appears to predict the likelihood of successful dose reduction.
Marks JL et al. Does combined clinical and ultrasound assessment allow selection of individuals with rheumatoid arthritis for sustained reduction of anti-tumor necrosis factor therapy? Arthritis Care Res. 2015 May;67(6):746–53.
Disclosure of Interest L. Serhal: None declared, C. Holroyd: None declared, J. Zarroug: None declared, R. Armstrong: None declared, B. Davidson: None declared, N. Harvey: None declared, E. Dennison: None declared, C. Cooper: None declared, C. Edwards Grant/research support from: Abbvie, MSD, Samsung, Novartis, Lilly, Sandoz, Celltrion, Celgene, Pfizer, BMS, Roche, Consultant for: Consultant, Speakers bureau: Speaker events