Study to assess if ABP798 is safe & effective in treating non Hodgkin lymphoma compared to rituximabJASMINE

- Males and females 18 years of age and older - Histological confirmed (by lymph node or extranodal region biopsy), Grade 1, 2, or 3a follicular B-cell NHL expressing CD20 within 12 months before randomization - Stage 2, 3, or 4 (per Cotswold’s Modification of Ann Arbor Staging System) with measurable disease (per International Working Group) • subjects must have a baseline scan (computed tomography [CT]) of the neck (if palpable lymph node > 1.0 cm), chest, abdomen, and pelvis to assess disease burden within 6 weeks before randomization • subjects must have had a baseline bone marrow biopsy within 12 months before randomization. Previously confirmed positive bone marrow involvement does not need to be repeated for purposes of screening. - Low tumor burden based on the Groupe d'Etudes des Lymphomes Folliculaires (GELF) criteria • largest nodal or extranodal mass ≤ 7 cm • no more than 3 nodal sites with diameter > 3 cm • no splenomegaly > 16cm by CT scan and no symptomatic splenomegaly • no significant pleural or peritoneal serous effusions by CT • lactate dehydrogenase ≤ upper limit of normal (ULN) • no B symptoms (night sweats, fever [temperature > 38°C], weight loss > 10% in the previous 6 months)

- Diffuse large cell component and/or Grade 3b follicular NHL - History or known presence of central nervous system metastases - Malignancy other than NHL within 5 years (except treated in-situ cervical cancer, or squamous or basal cell carcinoma of the skin) - Recent infection requiring a course of systemic anti-infective agents that was completed ≤ 7 days before randomization (with the exception of uncomplicated urinary tract infection) - Other investigational procedures that can impact the study data, results, or patient safety while participating in this study are excluded; participation in observational studies is allowed. - Subject is currently enrolled in or has not yet completed at least 30 days or 5 half-lives (whichever is longer) since ending other investigational device or drug study(s), including vaccines, or subject is receiving other investigational agent(s) - Previous use of either commercially available or investigational chemotherapy, biological, or immunological therapy for NHL (including rituximab or biosimilar rituximab, or other anti-CD20 treatments) - Systemic corticosteroid use within 3 months before randomization (inhaled are allowable)