A Study of JMT601 in Participants With Relapsed or Refractory CD20-positive B-cell Non-Hodgkin Lymphoma

Key Inclusion Criteria: * Participants diagnosed with CD20-positive B-cell non-Hodgkin lymphoma confirmed by histopathology and/or cell biology who have previously received 2 or more lines of therapy * Eastern Cooperative Oncology Group (ECOG) physical state score: 0-2 * Participants must have at least one evaluable or measurable lesion according to Lugano 2014 criteria. * Expected survival of at least 3 months; * Suitable organ and hematopoietic function: 1. The absolute count of neutrophil (ANC) ≥1.0×109/L; 2. Platelets ≥75×10\^9/L (if bone marrow invasion doesn't exist)/≥50.0×10\^9/L (if bone marrow invasion exists); 3. Hemoglobin ≥90 g/L; 4. Serum creatinine ≤1.5×ULN or creatinine clearance ≥50 mL/min; 5. Total bilirubin ≤1.5×ULN, alanine aminotransferase ≤2.5×ULN, aspartate aminotransferase ≤2.5×ULN; Subjects with liver lesion: TBIL≤3×ULN, ALT≤5×ULN, AST≤5×ULN; 6. International Standardized ratio and activated partial thromboplastin time ≤1.5 × ULN; Key Exclusion Criteria: * Confirmed central nervous system (CNS) lymphoma. * Subjects who have received allogeneic hematopoietic stem cell transplantation (HSCT) or other organ transplantation * Those who have previously received targeted CD47 or signal regulatory protein α (SIRRP α) therapy. * Previous or current hemolytic anemia, Evans syndrome, arteritis; * Subjects with previous or current other malignant tumors; * Previous or current history of active autoimmune diseases; * Subjects who had undergone major surgery within 4 weeks prior to initial dosing or expected to have major surgery during the study period; * HIV infection, active syphilis, hepatitis B surface antigen (HBsAg) positive and HBV-DNA higher than the lower limit or 1000 copies /ml(500 IU/ml), HCV antibody positive and HCV-RNA higher than the lower limit or 1000 copies /ml