IO Biotech presents data on IO102-IO103 vaccine at AACR 24

IO Biotech shared new data related to the company’s lead therapeutic cancer vaccine candidate, IO102-IO103, at the American Association for Cancer Research Annual Meeting 2024, taking place April 5-10, 2024, in San Diego, California. “These data build on earlier studies that demonstrated the mechanism of IO102 and IO103,” said Mai-Britt Zocca, Ph.D., President and CEO of IO Biotech. “We now clearly see that used together, IO102-IO103 create an environment in and around the tumor that allow for enhanced anti-tumor activity, at a much greater level than either could do on its own. With this additional data, we further understand the mechanistic rationale for the clinical effect observed in the Phase 1/2 study of IO102-IO103 that we hope to confirm in our ongoing Phase 3 pivotal study.” The data presented in the AACR poster are from two different animal tumor models and show that vaccines targeting IDO1 and PD-L1 expressing cells can cooperatively reduce tumor growth with each contributing to the anti-tumor effect through distinct molecular pathways. Where high levels of IDO1 and PD-L1 expression were seen in the tumor microenvironment, the IDO1 vaccine predominantly reduced myeloid-derived immune suppression, while the PD-L1 vaccine enhanced anti-tumor T-effector functions. In contrast, where IDO1 and PD-L1 expression was lower, the IDO1 vaccine resulted in a clear increase in T cell infiltration and activation and the PD-L1 vaccine impacted the myeloid cell compartment. While further studies are needed to fully discern the relationship between IDO1+/PD-L1+ target populations within the TME and the impact of IDO1/PD-L1 targeted vaccination, our data support the use of a dual antigen approach to reduce the immunosuppression and enhance anti-tumor effect.