This Phase 3 study is designed to evaluate the efficacy and safety of romiplostim in combination with predniso(lo)ne compared with predniso(lo)ne alone in adults with previously untreated Primary Immune Thrombocytopenia (ITP).
Age ≥18 years or adult legal age within country if older than 18 years.
Diagnosis of primary ITP according to the 2019 International Consensus (ICR) that is previously untreated and requires treatment.
Note: The investigator should ensure that the diagnosis of primary ITP is established by excluding other causes of isolated thrombocytopenia, as outlined in the 2019 ICR, which states that the diagnosis of primary ITP is principally based on the exclusion of other causes of isolated thrombocytopenia.
Note: If emergency treatment is necessary, platelet count performed before emergency can be used for study inclusion.
Life-threatening bleeding at randomization.
Known sensitivity or intolerance to any of the products to be administered during study (eg, uncontrolled diabetes) or to any Escherichia coli-derived product (eg, filgrastim, pegfilgrastim, certain insulins).
Uncontrolled hypertension before randomization.
Abnormal hepatic or renal function at screening.