The purpose of this study is to evaluate the safety, tolerability, and efficacy of MEDI4736 (durvalumab) alone and in combination with either tremelimumab or AZD9150 in adult subjects with relapsed or refractory dIffuse large B-cell lymphoma.

This is a multicenter, open-label, dose-escalation and dose-expansion study of MEDI4736 (durvalumab) as monotherapy or in combination with either tremelimumab or AZD9150. The objectives are to describe any dose-limiting toxicities, determine the maximum tolerated dose, and evaluate the safety, tolerability, efficacy, immunogenicity, pharmacokinetics, and pharmacodynamics of MEDI4736 as monotherapy or in combination with either tremelimumab or AZD9150 in adult subjects with relapsed or refractory diffuse large B-cell lymphoma.

Inclusion Criteria:

1. Age ≥ 18 years
2. Subjects with histologically confirmed relapsed or refractory DLBCL who have received at least 1 prior rituximab containing chemotherapy regimen but no more than 5 prior lines of therapy
3. Eastern Cooperative Group (ECOG) performance status of 0 or 1
4. Measurable disease by International Working Group (IWG) response criteria for lymphoma
5. Adequate organ and marrow function

Exclusion Criteria:

1. Previous immune-mediated therapy
2. Subjects with prior ASCT or allogenic HCT. Subjects ineligible for available curative options after failing ASCT and have met the hematologic criteria are eligible to participate in this study. Subjects with prior allogenic HCT will be excluded.
3. Documented current central nervous system involvement

3. Active or prior documented autoimmune or inflammatory disease within 3 years, with some exceptions 4. Concurrent or prior conventional or investigational anticancer therapy, within 28 days prior to the first dose of study medication(s)