The overall survival of patients with advanced ovarian cancer (OC) remains poor. The response to immunotherapy, including to PD-1/PD-L1 blockade, is very low, as demonstrated in various published trials. PD-1/PD-L1 inhibitors represent a promising treatment strategy and is the most widely studied immunotherapy across several cancer types. The ability to make ovarian tumors more sensitive to anti-PD-1/PD-L1 treatment would improve the prognosis and quality of life of numerous ovarian cancer patients. Through the support of the SCI Women's Cancer Center Innovation award, Dr. Dorigo proposes the first study in ovarian cancer to investigate the use of two compounds: the LTbR agonist 5G11b and the anti-CTLA4 antibody 9D9-IgG2a, with the aim to sensitize ovarian cancers to anti-PD-1/PD-L1. Both 5G11b and 9D9-IgG2a have been shown, in other cancer types, to induce the presence of tertiary lymphoid structures (TLS) and their associated high endothelial venules (HEV), which are increasingly recognized as favorable markers of prognosis and have been implicated as mediators of immunotherapy efficacy. Dr. Dorigo will evaluate if treatment with 9D9-IgGa – alone and in combination with 5G11b – can induce TLS formation and sensitize tumors to anti-PD-1/PD-L1, potentially resulting in the development of a new therapy.