Single-arm, open-label, single-center study to evaluate the efficacy and safety of teriflunomide for the treatment of adults with steroid-resistant/relapse immune thrombocytopenia (ITP).

This is a prospective, single-arm, open-label study of teriflunomide in approximately 40 patients with ITP who have relapsed or have an insufficient response to prior therapies. Teriflunomide is administered as 7 mg orally once daily with dose adjustments for 24 weeks. Efficacy and safety outcomes are assessed on scheduled study visits.

Inclusion Criteria:

1. Diagnosis of primary immune thrombocytopenia (ITP) by excluding other supervened causes of thrombocytopenia
2. Patients with a platelet count <30,000/μL or a platelet count <50,000/μL with bleeding manifestations at the enrollment;
3. Patients who did not achieve a sustained response to treatment with full-dose corticosteroids for a minimum duration of 4 weeks or who relapsed during steroid tapering or after its discontinuation;
4. Willing and able to sign written informed consent.

Exclusion Criteria:

1. Received chemotherapy or anticoagulants or other drugs affecting the platelet counts within 6 months before the screening visit;
2. Secondary immune thrombocytopenia (e.g. patients with HIV, HCV, Helicobacter pylori infection, malignancy, or patients with confirmed autoimmune disease);
3. Pregnancy or lactation;
4. Pre-existing acute or chronic liver disease, or serum alanine aminotransferase (ALT) greater than 2 times the upper limit of normal (ULN);
5. Current or recent (< 4 weeks prior to screening) clinically serious viral, bacterial, fungal, or parasitic infection;
6. Have evidence of active tuberculosis (TB), or have previously had evidence of active TB and did not receive appropriate and documented treatment, or have had household contact with a person with active TB and did not receive appropriate and documented prophylaxis for TB;
7. Patients who are deemed unsuitable for the study by the investigator.