The purpose of this study is to determine whether treatment with IBI110 single agent and in combination with sintilimab demonstrates sufficient efficacy/safety in r/r DLBCL.

This is a phase Ib, open-label, randomized study to determine the efficacy and safety of treatment with IBI110 single agent and in combination with sintilimab in DLBCL that are relapsed and/or refractory to available standard of care therapies.

Participants in each cohort are randomly assigned to one of the two arms: IBI110 single agent arm and IBI110 in combination with sintilimab arm. Participants received study treatment for a maximum of 2 years, or until disease progression (assessed by investigator per Lugano 2014 Criteria for Malignant Lymphoma (Cheson et al 2014)), unacceptable toxicity, death or discontinuation from study treatment for any other reason.

Inclusion Criteria:

• Provide signed written informed consent, which includes compliance with the requirements and restrictions listed in the consent form.
• Male or female, 18-70 years old (at the time consent is obtained)
• Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1.
• Histologically confirmed diagnosis of DLBCL in a subject who has been pretreated with at least 2 lines of systematic treatment (regimens containing anthracyclines and anti-CD20 immunotherapy must be included);
• Subjects whose most recent therapy was CAR-T cell therapy were also eligible.

Exclusion Criteria:

Patients previously exposed to any anti-LAG-3 treatment.

• History of ≥Grade 3 CRS, neurotoxicity, or hemophagocytic lymphohistiocytosis) during previous CAR-T cell therapy.
• Impaired cardiac function or clinically significant cardiac disease.
• Active, known or suspected autoimmune disease or a documented history of autoimmune disease within two years prior to screening with a few exceptions as per protocol.