Efficacy and Safety of Zuberitamab Combined with Bendamustine, Followed by Monotherapy Maintenance, in Treatment-naïve Follicular Lymphoma

Inclusion criteria

• Voluntary signing of informed consent.
• Age ≥ 18 years, no gender restriction.
• Histologically confirmed follicular lymphoma (grades 1-3a), CD20 positive by immunohistochemistry.
• No prior systemic treatment for FL.
• Ann Arbor stage III/IV, or stage II with bulky disease (bulky disease defined as a tumor diameter ≥ 7 cm).
• Presence of measurable lesions.
• Meeting any of the following criteria:

• B symptoms: unexplained fever >38°C, night sweats, unexplained weight loss >10% in the last 6 months.
• Abnormal signs: splenomegaly, pleural effusion, ascites, etc.
• Major organ damage: involvement of major organs leading to organ dysfunction.
• Hematologic involvement: cytopenia [WBC < 1.0 × 10⁹/L and/or PLT < 100 × 10⁹/L]; leukemia-like manifestations (malignant cells > 5.0 × 10⁹/L); elevated LDH levels; HGB < 120 g/L; β2-microglobulin ≥ 3 mg/L.
• Bulky disease: involvement of ≥ 3 tumors with each diameter ≥ 3 cm, or any lymph node or extranodal tumor with diameter ≥ 7 cm (for Ann Arbor stage III-IV patients).
• Tumor enlargement of 20%-30% within 2-3 months, or approximately 50% enlargement within 6 months.
• Eastern Cooperative Oncology Group (ECOG) performance status of 0, 1, or 2.
• Expected survival of > 6 months.

Exclusion criteria

• History of allergy to any component of monoclonal antibodies or investigational drugs.
• Central nervous system involvement.
• History of previous malignant tumors.
• Clinically significant cardiac or pulmonary diseases.
• Infection requiring intravenous antibiotic treatment or hospitalization within 4 weeks prior to enrollment; or infection requiring oral antibiotics within 2 weeks prior to enrollment; or symptoms related to an infection within 1 week prior to enrollment.
• Major surgery within 4 weeks prior to enrollment.
• Vaccination with live vaccines within 4 weeks prior to enrollment or planned live vaccination during the study.
• HIV antibody positive.
• Active syphilis infection, TP antibody positive, and anti-TP treatment within the last 2 years.
• Hepatitis C virus (HCV) antibody positive with HCV RNA quantitative test result exceeding the detection limit; Hepatitis B surface antigen (HBsAg) positive or Hepatitis B core antibody (HBcAb) positive, with Hepatitis B virus DNA quantitative test result exceeding the detection limit (for patients with HBsAg or HBcAb positive status, regardless of HBV-DNA detection, oral entecavir or other antiviral therapy must be initiated prior to enrollment and continued according to the physician's instructions during the trial).
• Pregnant or breastfeeding women, or planning to become pregnant during the study.
• Investigator determines the patient is unsuitable for enrollment or may not be able to complete the trial for other reasons.