Efficacy and Safety of QL0911 in Adult Patients With Chronic Primary Immune Thrombocytopenia

This study consisted of a randomized, double-blind, placebo-controlled, 26-week treatment period, sequentially followed by an open-label, single-arm, 12-week treatment period, and an additional 4-week safety follow-up period.

Inclusion criteria

• Aged ≥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;
• Eastern Cooperative Oncology Group (ECOG) performance status of 0, 1, or 2;
• Fully understand and comply with the requirements of this study, and voluntarily sign the informed consent form.

Exclusion criteria

• Had a history of bone marrow stem cell abnormalities or myelodysplastic syndrome other than ITP-specific changes.
• Had arterial thrombosis, or venous thromboembolism; severe cardiovascular diseases; malignant tumors; secondary thrombocytopenia caused by autoimmune diseases.
• 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), and hematopoietic growth factors (HGFs) within 4 weeks before the first dose;
• Had received antineoplastic agents within 8 weeks before the first administration, but when treating ITP with hypomethylating agents (HMA) such as decitabine, a 4-week washout period was acceptable, as judged by the investigator;
• Had received antibody-based therapies within 14 weeks before the first dose; 8) had serum creatinine or total bilirubin >1.5 upper limit of normal (ULN), alanine transaminase (ALT) or aspartate transaminase (AST) >3 ULN, hemoglobin < 100g/L, absolute neutrophil count <1.5x10^9/L;
• Had prothrombin time (PT) or prothrombin time-international normalized ratio (PT-INR) or activated partial thromboplastin time (APTT) exceeded 20% of the reference range of normal values.