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

The purpose of this study is to demonstrate the clinical efficacy of rozanolixizumab in maintenance treatment and assess safety and tolerability of rozanolixizumab in adult study participants with primary immune thrombocytopenia (ITP).


Eligibility Criteria:
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 (\>12 months duration) primary immune thrombocytopenia (ITP) at the Screening Visit
* Study participant has a documented intolerance or insufficient response to two or more appropriate 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 time periods prior to Baseline (Day 1)
* Study participant has a documented history of low platelet count (\<30×10\^9/L) prior to Screening
* 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 (using local laboratories)
* Study participant has a current or history of a peripheral blood smear consistent with ITP
* Study participants may be male or female:

  1. A male participant must agree to use contraception during the Treatment Period and for at least 3 months after the final dose of study treatment and refrain from donating sperm during this period
  2. A female participant is eligible to participate if she is not pregnant as confirmed by a negative serum pregnancy test and not planning to get pregnant during the participation in the study, not breastfeeding, and at least one of the following conditions applies:

Not a woman of childbearing potential (WOCBP) OR A WOCBP who agrees to follow the contraceptive guidance during the Treatment Period and for at least 3 months after the dose of study treatment

Exclusion Criteria:

* Participant has a history of arterial or venous thromboembolism (eg, stroke, transient ischemic 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 platelet adjustment (eg, menorrhagia with significant drop in hemoglobin)
* Study participant has a known hypersensitivity to any components of the study medication or any other anti-neonatal Fc receptor (FcRn) medications
* Study participant has evidence of a secondary cause of immune thrombocytopenia (clear association with other medical conditions, eg, untreated H. pylori infection, leukemia, lymphoma, common variable immunodeficiency, systemic lupus erythematosus, autoimmune thyroid disease or is drug induced), participant has a multiple immune cytopenia (eg, Evan's syndrome)
* Study participant has a clinically relevant active infection (eg, sepsis, pneumonia, or abscess) in the opinion of the investigator, or had a serious infection (resulting in hospitalization or requiring parenteral antibiotic treatment) within 6 weeks prior to the first dose of investigational medicinal product (IMP)
* Study participant with a known tuberculosis (TB) infection, at high risk of acquiring TB infection, or latent tuberculosis infection (LTBI), or current/history of nontuberculous mycobacterial infection (NTMBI)
* Study participant has a history of a major organ transplant or hematopoietic stem cell/marrow transplant
* Study participant has experienced intracranial bleed in the last 6 months prior to the Screening 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 Baseline Visit