Rituximab and Pegylated Interferon α-2b in Patients With Indolent B-cell Lymphoma

Inclusion Criteria: 1. 18 to 80 years of age, male or female; 2. Patients with a diagnosis of indolent B-cell non-Hodgkin's lymphoma (iNHL),including following subtypes：follicular lymphoma (grade Ⅰ, Ⅱ), intra-nodal and extra-mucosa-associated lymph Tissue marginal zone lymphoma (MALT), spleen marginal zone B-cell lymphoma, lymph node marginal zone lymphoma(MZL), Lymphocele lymphoma (except macroglobulinemia), small lymphocytic lymphoma(SLL); 3. Treatment naive, and Lugano stage III-IV; 4. Life expectancy at least 12 months; 5. At least one evaluable or measurable disease that meets the Lugano 2014 criteria for malignant lymphoma \[Evaluable lesions: 18 fluorodeoxyglucose-positron emission tomography (18FDG/PET) examination showed increased local uptake of lymph nodes or extranodal nodes (higher than liver) and PET and /or Computed Tomography (CT) features consistent with lymphoma features; Measurable lesions: nodular lesions\> 15mm in diameter or extranodal lesions\> 10mm (if only one measurable lesion has previously received radiotherapy, evidence of radiographic progression after radiotherapy is required), and accompanied by 18FDG increased intake\]. It is necessary to exclude cases where there is no measurable lesion and diffuse liver 18FDG uptake is increased; 6. ECOG score 0-2; 7. Organs and bone marrow function normally (within 14 days prior to study drug use, without receiving blood transfusion, granulocyte colony-stimulating factors or other related medical support): 1. Absolute value of neutrophils ≥1.0 × 109 / L; 2. Platelets ≥50 × 109 / L; 3. Hemoglobin ≥8 g / dL; 4. Serum creatinine ≤ 1.5 times Upper Limit Normal (ULN), or creatinine removal rate ≥40mL / min (estimated according to Cockcroft-Gault formula); 5. serum total bilirubin ≤ 1.5 times ULN; 6. Aspartate Aminotransferase (AST), Alanine Aminotransferase (ALT) ≤ 2.5 times ULN; 7. Coagulation function: International Normalized Ratio (INR)≤1.5 times ULN; Prothrombin Time (PT), Activated Partial Thromboplastin Time (APTT) ≤1.5 times ULN (unless the patient is receiving anticoagulant therapy and PT and APTT are within the expected range at the time of screening); 8. Female patients of childbearing age must have a negative pregnancy test at the time of enrollment and are willing to use reliable contraceptive methods, i.e. barrier methods, oral contraceptives, implant methods, skin contraception, long-acting injection contraceptives, intrauterine devices, or tubal ligation; 9. Sign the informed consent. Exclusion Criteria: 1. Primary CNS lymphoma or secondary CNS involvement; 2. A history of severe allergic reactions to humanized or murine monoclonal antibodies; 3. Patients have active autoimmune disease that requires systemic treatment in the past two years. (hormonal replacement therapy is not considered as a systemic treatment, such as patients with type 1 diabetes, adrenal function due to hypothyroidism that only requires thyroxine replacement therapy, low or pituitary dysfunction which only requires physiological doses of glucocorticoid replacement therapy); Patients with autoimmune disease without systemic treatment in the past two years can be enrolled; 4. Patients who require systemic glucocorticoid therapy or other immunosuppressive therapy within 14 days before study 【patients are permitted to use topical, ocular, intra-articular, intranasal, and inhaled corticosteroids (with very low systemic absorption), to receive short-term (≤ 7 days) preventive treatment with glucocorticoids (such as contrast agent hypersensitivity) or treatment of non-autoimmune diseases (such as delayed onset of hypersensitivity caused by contact allergen】.Low-dose hormone debulking treatment due to large tumor burden is allowed (prednisone 20mg × 7 days or equivalent dose of other hormones are allowed); 5. Have other malignancies in the past 5 years, except for basal cell carcinoma of the skin, squamous cell carcinoma of the skin, carcinoma in situ of the breast and carcinoma in situ of the cervix after radical treatment; 6. Within 28 days before study treatment, patients receiving systemic anti-tumor treatments, including chemotherapy, immunotherapy, biotherapy (tumor vaccine, cytokine, or growth factor that controls cancer); 7. Major surgery was performed within 28 days before study treatment, or radiotherapy was performed within the first 90 days; 8. Within 7 days before study treatment, patients receiving anti-cancer Chinese herbal medicine or proprietary Chinese medicine treatment; 9. Live vaccines (excluding influenza attenuated vaccines) within 28 days before study treatment; 10. A history of Human Immunodeficiency Virus (HIV) disease Patients with viral infection and / or acquired immunodeficiency syndrome; 11. Patients with active chronic hepatitis B or active hepatitis C. Patients who are Hepatitis B Surface Antigen (HBsAg) or Hepatitis C Virus (HCV) antibodies positive during the screening period must have the Hepatitis B Virus (HBV) DNA titer test (must not higher than 2500 copies/mL or 1000 I /mL) and HCV RNA test (not to exceed the detection limit of the assay 10,000 copies/mL). Patients can enter the study if there is no treatment require. Patients with carriers of hepatitis B virus, stable hepatitis B after treatment (DNA titers of no more than 2500 copies / mL or 1000 IU / mL), and cured hepatitis C can be enrolled; 12. Any active infection requiring systemic anti-infective treatment within 14 days study treatment; 13. Female patients during pregnancy or lactation; 14. Patients with a history of alcohol or drug abuse; 15. Suffering from uncontrollable comorbidities, including but not limited to symptomatic congestive heart failure, uncontrollable hypertension, unstable angina pectoris, active peptic ulcer or bleeding disorders; 16. A history of interstitial lung disease or non-infectious pneumonia. Patients who previously had drug-induced or radioactive non-infectious pneumonia but were asymptomatic were admitted; 17. Patients with a history of mental illness, inability or restricted ability; 18. On the judgement of the investigator, patient's underlying condition may increase his or her risk when receiving study medications or confuse the occurrence of a toxic reaction and its judgment； 19. Patients of considered by investigators unsuitable for this study.