The Safety and Efficacy of Daratumumab in Patients With Refractory Aplastic Anemia

This study consists of two phases, phase Ib and phase II. The primary objective of phase Ib is to evaluate the safety and tolerability of multiple doses of daratumumab in patients with refractory aplastic anemia. The primary objective of phase II is to preliminarily assess the efficacy of multiple doses of daratumumab in patients with refractory aplastic anemia. Secondary objectives include evaluation of other efficacy endpoints, safety (phase II), and pharmacodynamic characteristics of multiple doses of daratumumab in these patients. The exploratory objective is to assess biological functional changes in peripheral blood and bone marrow before and after daratumumab treatment.

Inclusion Criteria: 1. Clearly diagnosed with primary acquired aplastic anemia according to the Chinese Guidelines for the Diagnosis and Treatment of Aplastic Anemia (2022 Edition). 2. Refractory aplastic anemia meeting one of the following criteria: 2.1 Patients previously diagnosed with severe aplastic anemia (SAA) # or transfusion-dependent non-severe aplastic anemia (TD-NSAA) \&: have received antithymocyte/antilymphocyte globulin (ATG/ALG) combined with standard-dose cyclosporine for at least 6 months, and standard-dose thrombopoietin (TPO) receptor agonist\* therapy for at least 4 months, but showed no response or relapsed; 2.2 Patients previously diagnosed with non-transfusion-dependent non-severe aplastic anemia (NTD-NSAA): have received standard-dose cyclosporine for at least 6 months, and standard-dose thrombopoietin (TPO) receptor agonist\* therapy for at least 4 months, but showed no response or relapsed. 3. Hemoglobin \