Effect of Tocilizumab on growth impairment in systemic juvenile idiopathic arthritis with long-term corticosteroid therapy

Abstract

Background. The safety and efficacy of tocilizumab (TCZ), an anti-IL-6 receptor monoclonal antibody, have been reported in the treatment of children with systemic juvenile idiopathic arthritis (sJIA).

Objectives. Growth of children during the TCZ study was analyzed.

Methods. Forty-five sJIA patients (8.1 ± 4.2 years) were enrolled. Mean standard deviation score (SDS) for height (HTSDS), height velocity (HVSDS) and changes in SDS from baseline (∆SDS) were determined. Correlation between ∆SDS and several factors such as age, disease duration and corticosteroid exposure were evaluated. Yearly height velocity was analyzed for 28 patients for whom we had data for 1 year prior to TCZ administration and who had received TCZ for more than 1 year.

Results. Of the 45 patients, 38 (84%) obtained a clinical response at week 144. The mean baseline HTSDS was − 2.7 ± 2.0 and inversely correlated with disease duration. Significant improvement was seen in change in HVSDS from 1 year prior to 1 year after baseline (− 6.0 ± 4.0 to − 2.5 ± 3.9, p = 0.0064). Reduction in corticosteroid exposure was significantly associated with improvement in HVSDS (p = 0.0027).

Conclusions. Growth impairment evidenced by HTSDS was more prominent in patients with longer standing disease. Catch-up growth was observed in patients who required less or no corticosteroid during TCZ treatment.

Keywords:

• Growth impairment
• JIA
• Tocilizumab
• IL-6

Acknowledgements

The authors thank Tomo Nozawa, Taichi Kanetaka, Masako Kikuchi, Tomoyuki Imagawa (Yokohama City University), Naomi Iwata (Aichi Children's Health and Medical Center), Hiroaki Umebayashi (Miyagi Children's Hospital), Kazuko Kasai (Kobe Children's Hospital), Shuji Takei, Yukiko Nonaka (Kagoshima University), Yuzaburoh Inoue (Chiba University) and Takuji Murata (Osaka Medical School) for helpful discussions, outpatient care and involvement in the study procedures.

Funding

This study was sponsored by Chugai Pharmaceuticals Co, Ltd. Editorial support was provided by Genentech Inc, a member of the Roche group.

Conflict of interests

None.