A Study to Assess the Efficacy, Safety, and Tolerability of Rozanolixizumab in Adult Study Participants With Persistent or Chronic Primary Immune Thrombocytopenia (ITP)

Inclusion Criteria:

• Study participant must be ≥18 years of age at the time of the Screening Visit
• Study participant has a diagnosis of persistent (>3 months duration) or chronic (>12months duration) primary immune thrombocytopenia (ITP) at the Screening Visit
• Study participant has a documented intolerance or insufficient response to two or moreappropriate standard of care ITP treatments prior to Screening
• Study participants must have prior history of a response to a previous ITP therapy.
• If taking allowed drugs, study participant must be on stable doses during defined timeperiods prior to Baseline (Day 1)
• Study participant has a documented history of low platelet count (<30×10^9/L) prior toScreening
• Study participant has a platelet count measurement at Screening and at Baseline (Day

1. with an average of the two <30×10^9/L and no single count may be >35×10^9/L (usinglocal laboratories)

• Study participant has a current or history of a peripheral blood smear consistent withITP
• Study participants may be male or female:

1. A male participant must agree to use contraception during the Treatment Periodand for at least 3 months after the final dose of study treatment and refrainfrom donating sperm during this period
2. A female participant is eligible to participate if she is not pregnant asconfirmed by a negative serum pregnancy test and not planning to get pregnantduring the participation in the study, not breastfeeding, and at least one of thefollowing conditions applies: Not a woman of childbearing potential (WOCBP) OR A WOCBP who agrees to follow thecontraceptive guidance during the Treatment Period and for at least 3 months after the doseof study treatment

Exclusion Criteria:

• Participant has a history of arterial or venous thromboembolism (eg, stroke, transientischemic attack, myocardial infarction, deep vein thrombosis or pulmonary embolism)within the 6 months prior to randomization or requires current anticoagulant treatment
• Study participant has clinically significant bleeding that warrants immediate plateletadjustment (eg, menorrhagia with significant drop in hemoglobin)
• Study participant has a known hypersensitivity to any components of the studymedication or any other anti-neonatal Fc receptor (FcRn) medications
• Study participant has evidence of a secondary cause of immune thrombocytopenia (clearassociation with other medical conditions eg, of untreated H. pylori infection,leukemia, lymphoma, common variable immunodeficiency, systemic lupus erythematosus,autoimmune thyroid disease or is drug induced), participant has a multiple immunecytopenia (eg, Evan's syndrome) etc.
• Study participant has a clinically relevant active infection (eg, sepsis, pneumonia,or abscess) in the opinion of the investigator, or had a serious infection (resultingin hospitalization or requiring parenteral antibiotic treatment) within 6 weeks priorto the first dose of investigational medicinal product (IMP)
• Study participant with a known tuberculosis (TB) infection, at high risk of acquiringTB infection, or latent tuberculosis infection (LTBI), or current/history ofnontuberculous mycobacterial infection (NTMBI)
• Study participant has a history of a major organ transplant or hematopoietic stemcell/marrow transplant
• Study participant has experienced intracranial bleed in the last 6 months prior to theScreening Visit
• Study participant has a history of coagulopathy disorders other than ITP
• Study participant with current or medical history of immunoglobulin A (IgA)deficiency, or a measurement of IgA <50 mg/dL at the Screening Visit
• Study participant has undergone a splenectomy in the 2 years prior to the BaselineVisit