In situ vaccination (ISV) triggers an immune response to tumor-associated antigens at one tumor site that can then tackle disease throughout the body. Here we report clinical and biological results of a phase I/II ISV trial in patients with low-grade lymphoma (NCT02927964) combining an intratumoral TLR9 agonist with local low-dose radiation, and ibrutinib (an inhibitor of B and T cell kinases). Adverse events were predominately low grade. The overall response rate was 50%, including one …