Tocilizumab in large-vessel giant cell arteritis and takayasu arteritis: multicentric observational comparative study

BackgroundTocilizumab (TCZ) has shown to be effective for large vessel vasculitis including giant cell arteritis (GCA) and Takayasu arteritis (TAK) (1-5). However, LVV-GCA and TAK show different demographic and clinical features that may influence on TCZ therapeutic response.ObjectivesTo compare the effectiveness of TCZ in patients with LVV-GCA and patients with TAK.MethodsObservational multicenter study of patients with LVV-GCA and TAK who received TCZ. Outcome variables were: a) proportion of patients who achieved complete clinical improvement along with normalization of laboratory markers (CRP ≤0.5mg/dL and/or ESR ≤ 20 mm/1st hour) at 12 months b) complete improvement in imaging techniques. A comparative study between patients with LVV-GCA and TAK was performed.ResultsWe evaluated 70 LVV-GCA and 57 TAK patients who received TCZ. Main clinical and demographic characteristic are described in Table 1. Patients with TAK were younger, had longer disease duration, had received more commonly previous biologic therapy and were receiving higher doses of prednisone at baseline. TCZ intravenous administration was more common in TAK patients (80.7% vs 48.6%; p<0.01). Follow-up time after TCZ onset was similar in both groups. At 12 months, about 75% of patients achieved complete clinical improvement and ESR/CRP normalization in both groups. A follow-up imaging technique was performed in 37 LVV-GCA patients after a mean time of 12.9±6.0 months and 38 TAK patients after 9.5±5.0 months. Complete improvement in imaging techniques was only observed in 18.9% and 21.1% of patients with LVV-GCA and TAK, respectively (Figure 1).Table 1.LVV-GCA (n=70)TAK (n=57)pGeneral featuresAge (years), mean ± SD67.2 ± 10.540.5 ± 16.3< 0.01Sex (female), n (%)51 (72.9)49 (86)0.07Disease evolution before TCZ onset (months), median [IQR]5 [2-15]12 [3-37]<0.01Baseline laboratory parametersESR (mm/1st hour), median [IQR]32 [12.5-54.7]31 [10-52]0.82CRP (mg/dL), median [IQR]1.4 [0.5-2.4]1.4 [0.5-3.5]0.41Baseline prednisone dose (mg/day), median [IQR]15 [10-20]30 [15-50]< 0.01Previous therapyConventional DMARDs, n(%)45 (64.3)44(77.2)0.51Biologic therapy, n (%)0(0)12 (21.1)<0.01TCZ therapyIntravenous, n (%)34 (48.6)46 (80.7)< 0.01Combined with MTX, n(%)24 (34.3)24 (42.1)0.37Follow-up time after TCZ onset, median [IQR]20 [10-36]18 [7-41]0.73Complete clinical improvement and ESR/CRP normalization at 12 months, n/N (%)35/47 (74.4)30/39 (76.9)0.79Complete improvement in imaging techniques, n/N(%)7/37 (18.9)8/38 (21.1)0.85CRP: C-reactive protein; DMARDs: Disease-modifying anti-rheumatic drugs ESR: erythrocyte sedimentation rate; GCA: giant cell arteritis; IQR: interquartile range; LVV: large vessel; MTX: methotrexate; n: Number of patients; N: total number of patients: TCZ: tocilizumab; TAK:takayasuFigure 1.ConclusionThe effectiveness of TCZ was similar in patients with LVV-GCA and TAK, despite a more refractory disease in TAK patients. A discordance between clinical and imaging activity improvement was observed in both LVV-GCA and TAK, as reported in previous studies (3).References[1]Calderón-Goercke M, et al. Semin Arthritis Rheum 2019; 49:126-35. https://doi.org/10.1016/j.semarthrit.2019.01.003[2]Prieto-Peña D et al. Ther Adv Musculoskelet Dis. 2021;13:175. PMID: 34211589.[3]Prieto Peña D et al. Clin Exp Rheumatol. 2021;39 Suppl 129:69-75. PMID: 33253103.[4]González-Gay MA, et al. Expert Opin Biol Ther. 2019;19:65-72. doi: 10.1080/14712598.2019.1556256.[5]Prieto-Peña D, et al. Semin Arthritis Rheum. 2019;48(4):720-727. doi: 10.1016/j.semarthrit.2018.05.007Disclosure of InterestsNone declared