A Study to Evaluate the Efficacy and Safety of Golcadomide in Combination With Rituximab in Participants With Newly Diagnosed Advanced Stage Follicular Lymphoma

Inclusion Criteria

* 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).

Exclusion Criteria

* Clinical evidence of transformed lymphoma by investigator assessment.
* Follicular Large Cell as per WHO 5th classification or Grade 3b follicular lymphoma as per WHO 4th classification.
* Participant has any significant medical condition, active infection, laboratory abnormality, or psychiatric illness that would prevent the participation in the study.
* Other protocol-defined Inclusion/Exclusion criteria apply.