The purpose of this study is to evaluate the safety, tolerability, and pharmacokinetics of parsaclisib in the treatment of Japanese participants diagnosed with previously-treated B-cell lymphoma.

Inclusion Criteria:

• First generation Japanese; subject was born in Japan and has not lived outside of Japan for > 10 years, and subject can trace maternal and paternal Japanese ancestry.
• Histologically confirmed aggressive/indolent DLBCL, FL, MZL, or MCL.
• Previously received at least 1 prior line of systemic therapy with documented progression, and there is no further effective standard anticancer therapy available.
• Willing to undergo an incisional or excisional lymph node or tissue biopsy or to provide a lymph node or tissue biopsy from the most recent available archival tissue.
• Life expectancy > 3 months.
• Eastern Cooperative Oncology Group performance status of 0 to 2.
• Adequate hematologic, hepatic, and renal function.

Exclusion Criteria:

• Evidence of transformed non-Hodgkin's lymphoma histologies.
• Histologically confirmed, rare non-Hodgkin's B-cell subtypes.
• History of central nervous system lymphoma (either primary or metastatic) or leptomeningeal disease.
• Prior treatment with idelalisib, other selective PI3Kδ inhibitors, or a pan-phosphatidylinositol 3 kinase (PI3K) inhibitor.
• Allogeneic stem cell transplant within the last 6 months or autologous stem cell transplant within the last 3 months before the date of the first dose of study drug.
• Active graft-versus-host disease.
• History of stroke or intracranial hemorrhage within 6 months of study drug administration.
• Chronic or current active infectious disease requiring systemic antibiotics, antifungal, or antiviral treatment or exposure to a live vaccine within 30 days of the date of the first dose of study drug.
• Known human immunodeficiency virus infection.
• Evidence of hepatitis B virus or hepatitis C virus infection or risk of reactivation.

Data will be made available at the end of trial or termination of trial. The following data will be made available: safety, PK and PD, efficacy, and subject characteristics. The results of the trial will be published. In addition, data as documented in study CSR will be made available upon request.