Teclistamab in Newly Diagnosed Mayo Stage IIIB AL Amyloidosis

Inclusion Criteria: * Biopsy confirmed AL amyloidosis * Mayo 2004 stage IIIB * dFLC ≥ 50mg/L Exclusion Criteria: * Co-morbidity of uncontrolled infection * Co-morbidity of other active malignancy * Co-diagnosis of multiple myeloma or waldenstrom macroglobulinemia * Co-morbidity of grade 2 Mobitz II or grade 3 atrioventricular block (expect for those with implanted pacemaker) * Co-morbidity of sustained or recurrent nonsustained ventricular tachycardia * Seropositive for human immunodeficiency virus * Hepatitis B virus (HBV)-DNA \> 1000 copies/mL * Seropositive for hepatitis C (except in the setting of a sustained virologic response) * Neutrophil \<1×10E9/L, hemoglobin \< 8g/dL, or platelet \< 75×10E9/L. * Severely compromised hepatic or renal function: alanine transaminase (ALT) or aspertate aminotransferase (AST) \> 5 × upper limit of normal (ULN), total bilirubin \> 2 × ULN, estimated glomerular filtration rate \< 20 mL/min, or receiving renal replacement therapy