A Prospective, One-arm and Open Clinical Study of Obinutuzumab in the Treatment of Pediatric Primary Immune Thrombocytopenia (ITP)

Inclusion Criteria:

• Age 12-18 years old, male or female

• Conform to the diagnostic criteria of persistent or chronic immune Thrombocytopenia (ITP)

• With a platelet count of <30 X 10^9/L measured within 2 days prior toadministration（Platelet counts were measured at least 2 times during screening (atleast 1 week apart) with platelets<30 X 10^9/L）

• Failure or recurrence of previous hormonal therapy or hormone dependence

• The previous emergency treatment of ITP (e.g. methylprednisolone, platelettransfusion, IVIG transfusion) must be completed at least 2 weeks before the firstadministration

• Signed and dated written informed consent

• With Liver and kidney function<1.5×upper limit of normal， such asALT、AST，BUN，Cre，etc.

• ECOG physical state score ≤ 2 points

• Cardiac function of the New York Society of Cardiac Function ≤ 2

• Patients receiving maintenance treatment (including corticosteroids (less than orequal to 0.5mg/kg prednisone), TPO receptor agonists, etc.) must have a stable doseat least 4 weeks before the first administration, and azathioprine, danazol,cyclosporin A, tacrolimus, sirolimus, etc. must be stopped at least 4 weeks beforethe first administration; The end of rituximab treatment was>3 months；More than 6months after splenectomy.

Exclusion Criteria:

• Subjects with primary disease of important organs (liver, kidney, heart, etc.), orwith immune system diseases;

• Secondary thrombocytopenia caused by various reasons, such as connective tissuedisorders, bone marrow hematopoietic failure disease, myelodysplastic syndrome,malignancy, drugs, inherited thrombocytopenia, common variable immune deficiency,lymphoma, etc.;

• Subjects infected with human immunodeficiency virus (HIV);

• Uncontrollable or active infections during the screening period, including hepatitisB, hepatitis C, cytomegalovirus, EB virus, or positive syphilis antigen;

• Subjects with extensive and severe bleeding, such as hemoptysis, uppergastrointestinal hemorrhage, intracranial hemorrhage;

• Subjects with heart disease that requires treatment or hypertension that has beenjudged by researchers to be poorly controlled currently;

• Subjects with any venous or arterial thrombosis, atherosclerosis, and otherdiseases;

• Subjects with a history of malignant solid tumor or have received allogeneic stemcell transplantation or organ transplantation;

• Subjects with mental disorders who are unable to sign normal informed consent andconduct trials and follow-up;

• Subjects whose toxic symptoms caused by pre-trial treatment have not disappeared;

• Subjects with other serious diseases that may limit their participation in thistrial (diabetes; severe cardiac insufficiency; myocardial obstruction or unstablearrhythmia or unstable angina pectoris in the last 6 months; gastric ulcer; activeautoimmune disease, etc.);

• Subjects with septicemia or other irregular bleeding;

• Patients taking antiplatelet drugs at the same time;

• Any medical history or condition that the investigator deems unsuitable forparticipation in the study.