Background: Emerging evidence during the last two decades supports a pivotal role of Interleukin 6 (IL-6) in the pathogenesis of Systemic Sclerosis (SSc). Standard immunosuppressive agents are often inadequate to control disease activity in SSc patients and treatment failure of multiple regimens is frequent in real-world practice.
Objectives: To examine the efficacy and safety of interleukin-6 receptor inhibition by tocilizumab in selected real-world patients with SSc.
Methods: Twenty-one patients (20 women, 16 diffuse SSc, mean age: 52±10 years, mean disease duration: 6.4±3.7 years, all with negative rheumatoid factor and anti-cyclic citrullinated antibodies, none with overlap syndrome with RA) with active joint and skin involvement refractory to corticosteroids (n=21), methotrexate (n=17), cyclophosphamide (n=10), mycophenolate (n=7), rituximab (n=1), leflunomide (n=2), hydroxychloroquine (n=2), and hematopoietic stem cell transplantation (n=2) who received weekly tocilizumab (162 mg subcutaneously) in an academic center, were monitored prospectively. Changes in Eustar modified activity index (MAI), modified Rodnan skin score (mRSS), disease activity score (DAS)28, lung function tests (LFTs) and patient reported outcomes (PROs) were analyzed at one year of treatment and at the end of follow-up.
Results: One patient discontinued tocilizumab after 3 months due to inefficacy. During the first year of treatment, 12 patients achieved low disease activity (mean MAI change -2.9±1.8, p<0.001) and significant clinical improvement was evident in 12 patients regarding skin involvement (mean mRSS change: -6.9±5.9, p<0.001) and in 16 patients regarding polyarthritis (mean DAS28 change: -1.9±0.8, p<0.001); Accordingly, improvements were recorded for all PROs (all p<0.001) (
Conclusion: Tocilizumab was effective in refractory joint and skin involvement irrespective of SSc disease duration or subtype. Long-term retention rates and disease stabilization for most real-world patients suggest that tocilizumab might be a valuable choice for difficult-to-treat SSc.
Clinical and laboratory parameters and measures (mean ± SD) at baseline and after one year of treatment with tocilizumab in 20 patients with Systemic Sclerosis
Baseline | 1 st year | change | p | |
Modified activity index | 4.9 ± 1.6 | 2.0± 1.2 | -2.9 ± 1.8 | <0.001 |
mRSS | 21.5 ± 9.5 | 14.6 ± 6.6 | -6.9 ± 5.9 | <0.001 |
DAS28 | 5.3 ± 0.7 | 3.4 ± 0.6 | -1.9 ± 0.8 | <0.001 |
FVC (% of predicted) | 82 ± 19.5 | 79 ± 19.1 | -2.9 ± 12 | 0.389 |
DLCO (% of predicted) | 60.4 ± 16.3 | 61.1 ± 18.4 | 0.7 ± 12.3 | 0.844 |
ESR (mm/1 st hr) | 35.6 ± 17.2 | 12.9 ± 11.8 | -22.8 ± 19.1 | 0.001 |
CRP (mg/l) | 13.2 ± 12.5 | 1.2 ± 2.1 | -12 ± 13.1 | 0.006 |
SHAQ | 1.6 ± 0.8 | 1.0 ± 0.7 | -0.6 ± 0.5 | <0.001 |
VAS patient global score | 37.8 ± 16.8 | 60.5 ± 15.4 | 22.7 ± 20.3 | <0.001 |
VAS physician global score | 33.4 ± 13.2 | 63.2 ± 13.9 | 29.8 ± 15.6 | <0.001 |
mRSS: modified Rodnan skin score; DAS28: disease activity score 28; FVC: forced vital capacity; DLCO: diffusing lung capacity for carbon monoxide; ESR: erythrocyte sedimentation rate; CRP: c-reactive protein; SHAQ: scleroderma health assessment questionnaire; VAS: visual analogue scale
Disclosure of Interests: None declared