An Open-label Study of Povetacicept in Participants With Autoimmune Cytopenias

Inclusion Criteria

• •1. Indication-specific Criteria
• •1. Immune Thrombocytopenia (ITP)
• •* Documented persistent or chronic primary ITP of at least 12 weeks duration from diagnosis to Cycle 1 Day 1
• •* History of failure or relapse to at least 2 treatment regimens for ITP
• •* History of exposure to a TPO-RA unless otherwise contraindicated or unavailable
• •* Documented history of platelets \<30 × 10\^9/L
• •2. Warm Autoimmune Hemolytic Anemia (wAIHA)
• •* Diagnosis of primary wAIHA of at least 12 weeks duration documented with a current or prior positive direct antiglobulin test (DAT) for anti-IgG (±C3d)
• •* Documented history of anemia with hemoglobin ≤10 g/dL
• •* At least one of the following: (i) haptoglobin \< lower limit of normal (LLN) (ii) indirect bilirubin \> upper limit of normal (ULN) (iii) lactate dehydrogenase\>ULN
• •* History of failure or relapse to at least 2 treatment regimens for wAIHA
• •3. Cold Agglutinin Disease (CAD)
• •* Diagnosis of primary CAD of at least 12 weeks duration with all of the following: (i) chronic hemolysis (ii) polyspecific DAT positive (iii) monospecific DAT strongly positive for C3d (iv) cold agglutinin titer ≥64 at 4°C (v) IgG DAT ≤1+ (vi) no overt malignant disease
• •* Documented history of anemia with hemoglobin ≤10 g/dL
• •* Evidence of hemolysis during screening: (i) indirect bilirubin \>ULN and (ii) lactate dehydrogenase\>ULN or haptoglobin \<LLN
• •* History of failure or relapse to at least 1 treatment regimen for CAD
• •2. (All indications) If receiving protocol-specified standard-of-care medications, doses must be stable for protocol-specified durations