TLR9 Agonist SD-101, Anti-OX40 Antibody BMS 986178, and Radiation Therapy in Treating Patients With Low-Grade B-Cell Non-Hodgkin Lymphomas

PRIMARY OBJECTIVES: I. To determine the safety and tolerability of TLR9 agonist SD-101 (SD-101) in combination with anti-OX40 antibody BMS 986178 (BMS-986178) and local low-dose radiation in patients with low-grade B-cell lymphoma. Adverse events and grades to be assessed by Common Terminology Criteria for Adverse Events (CTCAE) II. To determine the recommended phase 2 dose (RP2D) of BMS-986178 in combination with intratumoral SD-101 and radiation in patients with low-grade B-cell lymphoma. SECONDARY OBJECTIVES: I. To evaluate preliminary efficacy by assessing overall response rate and progression-free survival after treatment with intratumoral SD-101 in combination with BMS-986178 and radiation in patients with low-grade B-cell lymphoma. OUTLINE: This is a phase I study of the combination of TLR9 agonist SD-101, anti-OX40 antibody BMS 986178, and local low-dose radiation therapy. Patients receive radiation therapy on days 1-2, TLR9 agonist SD-101 intratumorally on days 2, 9, 16, 23, and 30, and anti-OX40 antibody BMS-986178 intravenously (IV) on days 3, 30, 58, 86, 114, and 142 in the absence of disease progression or unacceptable toxicity. After completion of study treatment, patients are followed up every 3-6 months for 72 weeks.