Neutropenia During Tocilizumab Therapy Not Linked to Infection Risk in Juvenile Idiopathic Arthritis

Neutropenia was not associated with an increased risk for infection in patients with systemic and polyarticular-course juvenile idiopathic arthritis (JIA) being treated with tocilizumab therapy, according to study results published in The Journal of Rheumatology.

Researchers analyzed data from two phase 3 randomized controlled trials: TENDER (n=112) and CHERISH (n=188), which evaluated the use of tocilizumab in patients with systemic and polyarticular-course JIA, respectively. Data on worst common toxicity grade and absolute neutrophil count (ANC) were obtained from each patient. Subsequently, the relationships between various patient characteristics and lowest measured ANC were analyzed using univariate linear regression.

After analysis, the researchers found that in patients treated with tocilizumab, ANC was reduced to grade ≥3 in 5.9% and 25.0% of patients with polyarticular-course and systemic JIA, respectively. In addition, no rise in infection rate was seen during periods of neutropenia in either trial. In addition, they reported that ANC reductions in both trials were transient.

One key limitation of the study was the reduction in glucocorticoid dose that occurred during both trials.

“The data reported here support the idea that susceptibility to infections is a feature of JIA and the conclusion that inflammation [or] autoimmunity predisposes children to infections,” the researchers wrote.

“Patients with JIA treated with tocilizumab experienced transient neutropenia that was not associated with an increased number of infections,” they concluded.

Reference

Pardeo M, Wang J, Ruperto N, et al. Neutropenia during tocilizumab treatment is not associated with infection risk in systemic or polyarticular-course juvenile idiopathic arthritis [published online April 15, 2019]. J Rheumatol. doi:10.3899/jrheum.180795