A Study to Evaluate the Efficacy and Safety of Mezagitamab Subcutaneous Injection Compared With Placebo in Adults With Chronic Immune Thrombocytopenia

You may be able to join if

• The participant has been diagnosed with primary ITP that has persisted for at least 12 months. Diagnosis is in accordance with The American Society of Hematology 2019 Guidelines for ITP (Neunert et al. 2019) or the Updated International Consensus Report on The Investigation and Management of Primary ITP (Provan et al. 2019), as locally applicable.
• The participant’s diagnosis of ITP is supported by a prior response to an ITP therapy (not including a TPO-RA), defined as having achieved a platelet count ≥50,000/µL.
• The participant has evidence of insufficient response or intolerance to at least 1 currently available first-line therapy for treatment of ITP (for example, corticosteroids) and at least 1 currently available second-line therapy for treatment of ITP (for example, TPO-RA, rituximab, fostamatinib, mycophenolate). Insufficient response to previous treatment is defined as failure to achieve a sustained platelet count of at least 50,000/µL or doubling of baseline platelet count after an appropriate course of prior ITP treatment. Intolerance is defined as a documented side effect causing discontinuation of the therapy.
• The participant has a mean platelet count of <30,000/µL (with individual values ≤35,000/µL) from at least 2 consecutive measurements taken at least 5 days apart during screening (and may be inclusive of Day 1), including at least 1 of those measurements within 14 days before the first dose of investigational medicinal product (IMP) (Day 1).
• If the participant is receiving allowed standard-of-care treatment for ITP at screening and continued use is intended, treatment may continue during the trial if the dose and frequency have been stable for at least 4 weeks before receiving the first dose of IMP (ie, Day 1) and are expected to remain stable throughout the trial. Permitted concomitant treatments may include 1 medication from each of the following 3 categories: a) One thrombopoietin receptor agonist (eg, romiplostim, eltrombopag, avatrombopag, hetrombopag), and/or b) One oral corticosteroid given daily or every other day (not to exceed prednisone 20 mg daily or equivalent dose), and/or c) Fostamatinib. If participants do not plan to continue these agents during the trial, they must be washed out.