A single-arm, long-term efficacy and safety study of subcutaneous romiplostim in children with immune thrombocytopenia

•Long-term romiplostim treatment is effective in children with primary ITP; serial bone marrow biopsy results showed no new safety concerns.•Romiplostim injections resulted in 8 AEs of neutralizing antibodies (romiplostim, n = 7 [transient n = 4]; TPO, n = 1 [transient n = 1]). [Display omitted] Romiplostim is a thrombopoietin (TPO) receptor agonist approved for children and adults with immune thrombocytopenia (ITP) for ≥6 months, recommended as second-line treatment. This phase 3b, single-arm, multicenter study investigated long-term efficacy and safety of romiplostim in children ≥1 to