NCT06355739: Phase II Clinical Study on the Safety and Efficacy of Autotransfusion Agents Targeting CD19 Chimeric Antigen Receptor T Lymphocytes (BIC-19GG, BIC-2019,BIC-2219)in the Treatment of CD19-positive Children With Relapsed/Refractory B-cell Acute Lymphoblastic Leukemia/Lymphoblastic Lymphoma | TrialSignal