• Participant has histologically confirmed Grade 1, 2 or 3a follicular lymphoma (FL) or classic FL. Formalin-fixed paraffin embedded (FFPE) archival tissue from 1 year prior to screening is allowed. If more than 1 year has passed, then a fresh biopsy must be obtained to confirm the diagnosis.

• Have no prior systemic treatment for follicular lymphoma. Prior radiation therapy or surgery for previously diagnosed stage I disease is acceptable.

• Stage II to IV disease.

• Deemed to need treatment by treating investigator. Reasons for treatment can include, but are not limited to, the following:.

• i) Bulky disease defined as:.

⁃ A. A nodal or extra nodal (except spleen) mass \> 7cm in its greater diameter or, involvement of at least 3 nodal or extra nodal sites (each with a diameter greater than \>3 cm).

⁃ ii) Presence of at least one of the following B symptoms:.

⁃ A. Fever (\>38°C) of unclear etiology.

⁃ B. Night sweats.

⁃ C. Weight loss greater than 10% within the prior 6 months.

⁃ iii) Splenomegaly with inferior margin below the umbilical line.

⁃ iv) Any one of the following cytopenia due to lymphoma:.

⁃ A. Platelets \<100,000 cells/mm3 (100 x 109/L).

⁃ B. Absolute neutrophil count (ANC) \< 1,000 cells/mm3 (1.0 x 109/L).

⁃ C. Hemoglobin \< 10g/dL (6.25 mmol/L).

⁃ v) Pleural or peritoneal serous effusion (irrespective of cell content).

⁃ vi) Any compressive syndrome (for example, but not restricted to ureteral, orbital, gastrointestinal).