Can intravenous tocilizumab cause low neutrophil counts in children with systemic juvenile idiopathic arthritis?

Yes, intravenous tocilizumab can lower neutrophil counts in children aged 2–17 years with systemic juvenile idiopathic arthritis: counts below 1 × 10⁹/L occurred in 7% during the 12-week controlled phase versus none with placebo, and in 15% during the open-label extension.