Study to Assess the Safety and Tolerability of Tafasitamab in Adult Participants With Primary Autoimmune Blood Cell Disorders

Inclusion Criteria: \- Ability to comprehend and willingness to sign a written ICF for the study. * Aged ≥ 18 years. * Confirmed historical diagnosis of one of the following autoimmune blood disorders: * Primary ITP. * Primary wAIHA. * No history of splenectomy. * Confirmed transient response to at least 1 prior early-line treatment (eg, corticosteroids, IVIG, rituximab): * Primary ITP: Increase in platelet count to ≥ 30 × 109/L with at least a 2-fold increase of baseline platelet count. * Primary wAIHA: Increase in hemoglobin to ≥ 10 g/dL with an increase of at least 2 g/dL from baseline. * Received ≥ 1 standard course of rituximab (375 mg/kg × 4 weekly doses or 2 doses of 1000 mg flat dose every 2 weeks) with last dose given at least 6 months prior to initiation of study treatment. Note: If rituximab was the only prior therapy, individuals with NR to rituximab will not be eligible. * Primary ITP: a PR (platelet count ≥ 30 × 109/L with at least a 2-fold increase of baseline platelet count) within 6 months of the last administered dose followed by relapse OR a CR (platelet count \> 100 × 109/L) lasting \< 48 weeks OR NR (platelet count \< 30 × 109/L or less than 2-fold increase of baseline platelet count or bleeding) within 6 months of the last administered dose. * Primary wAIHA: a PR with hemoglobin ≥ 10 g/dL and with an increase of at least 2 g/dL from baseline OR a CR (hemoglobin ≥ 12 g/dL and normalization of hemolytic markers) OR NR (hemoglobin \< 10 g/d…