The purpose of this study is to evaluate efficacy and of safety QL0911 in the treatment of thrombocytopenia in pediatric patients with previously treated chronic ITP.
Age ≥ 1 years old and < 18 years old.
Diagnosed primary ITP for at least 12 months;
Had received at least one first-line ITP treatment with no response or recurrence after treatment;
Had a platelet count <30×10^9/L within 48 hours before the first dose;
Had a history of bone marrow stem cell abnormalities or myelodysplastic syndrome other than ITP-specific changes.
Underwent splenectomy within 12 weeks before the first dose;
Had received ITP treatments (including rescue treatment) within 2 weeks before the first dose;
Had received romiplostim (Nplate®) or eltrombopag (Revolade®), rhTPO or other agents that stimulate TPO receptors (also known as c-Mpl)within 4 weeks before the first dose;