To Evaluate Efficacy and Safety of Parsaclisib Plus Either Rituximab or Obinutuzumab in R/R Follicular Lymphoma (FL) and Marginal Zone Lymphoma (MZL) (CITADEL-302)

Inclusion Criteria: * Male and female participants aged 18 years or older (Japan, aged 20 years or older). * Histologically confirmed Grade 1, 2, or 3a FL or nodal MZL, splenic MZL, or extra nodal MZL * Prior systemic treatment with at least 1 anti-CD20 mAb (either as monotherapy or in combination as chemoimmunotherapy) * Documented disease that has relapsed or progressed or was refractory after the most recent prior systemic therapy. Note: Participants must not be refractory to anti-CD20 mAb * Radiographically (CT, MRI) measurable lymphadenopathy per the Lugano criteria for response assessment (Cheson et al 2014). * ECOG PS of 0 to 2 * Adequate organ functions including hematopoiesis, liver, and kidney * Willingness to avoid pregnancy or fathering children Exclusion Criteria: * Women who are pregnant or breastfeeding. * Known histological transformation from indolent NHL to an aggressive NHL (eg, diffuse large B-cell lymphoma). * Presence of CNS lymphoma (either primary or secondary) or leptomeningeal disease. * Prior treatment with PI3K inhibitors. * Inadequate washout of immunosuppressive therapy, anticancer medications and investigational drugs. * Significant concurrent, uncontrolled medical condition, including, but not limited to, renal, hepatic, hematological, GI, endocrine, pulmonary, neurological, cerebral, cardiac, infectious, or psychiatric disease. * Known HIV infection. * HBV or HCV infection: Participants positive for HBsAg or anti-HBc will be eligible if the…