Hetrombopag for Lower-risk MDS With Thrombocytopenia: a Prospective，Open-label, Single-arm Study.

Inclusion Criteria: * 18 years or older； * Confirmed diagnosis of MDS based on 2016 WHO (World Health Organization) and classification with very low, low or intermediate (score ≤ 3.5) risk according to the revised International Prognostic Scoring System (IPSS-R). * Platelets \< 30 x 10\^9/L or platelets \< 50 x 10\^9/L with active bleeding at screening. * Eastern Cooperative Oncology Group (ECOG) performance score ≤ 2； * Ability to understand information material and written informed consent. Exclusion Criteria: * Severe active bleeding/infection or any other uncontrolled severe condition; * History of treatment with thrombopoietin receptor agonists (eltrombopag, avatrombopag, romiplostim, etc.) or recombinant human thrombopoietin with 1 month prior; * Patients with known active hepatitis B, hepatitis C, or human immunodeficiency virus (HIV) at screening（If hepatitis B surface antigen or hepatitis B core antibody are positive, HBV-DNA testing are needed. If positive, it suggests a viral replication and subjects will be excluded. If hepatitis C antibody are positive, HCV-RNA testing are needed. If positive, it suggests a viral replication and subjects will be excluded）; * Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) \>2.5 x upper limit of normal (ULN), total bilirubin \>2.5 x ULN, creatinine \>1.5 x ULN; * History of portal hypertension or cirrhosis； * History of any types of solid tumors within 5 years prior, whether the tumors has been treated, metastasized or relapsed (except basal cell carcinoma); * History of congestive heart failure requiring medical management, cardiac arrhythmias, peripheral arteriovenous thrombosis within 1 years prior, or myocardial infarction or cerebral infarction within 3 months prior; * ECOG performance score ≥ 3; * Female subjects who are pregnant or breastfeeding, or subjects who are planning pregnancy within 6 months; * Women of child-bearing potential and men must agree to use contraception prior to study entry and for the duration of study participation; * Participated in other clinical trials within 3 months prior; * Any condition which, in the investigator's opinion, deems the subject an unsuitable candidate to receive study drug.