Abstract 3970: Targeting the adenosine immunosuppressive pathway for cancer immunotherapy with small molecule agents

Abstract Standard Immune Checkpoint Therapies, such as anti-CTLA-4 or anti-PD-1/PD-L1 mAb, demonstrate long progression-free-survival for responding patients but with a low response rate. This can be due to additional immunosuppressive mechanisms developed by resistant tumors. The adenosine pathway is one of the main drivers of tumor progression by acting on two key features of the TME (Tumor Micro-Environment); immunity and angiogenesis. Expression of CD73 on tumor cells and on immunosuppressive cell subsets leads to the generation of adenosine from AMP. Adenosine inhibits the biological functions of T lymphocytes infiltrating the tumor by binding to the A2AR (receptor). Evotec and Exscientia are collaborating to accelerate small molecule drug discovery in the field of Immuno-Oncology by integrating a unique biophysical screening approach to the adenosine receptors and CD73 to drive automated medicinal chemistry design with a translational-focused screening cascade, to discover novel agents that target the adenosinergic pathway in immuno-oncology. We have firstly sought to generate novel A2AR antagonists and secondly to create A2AR/CD73 bi-specific inhibitory molecules with a dual pharmacological profile, from fragment screening and de novo design approaches. In vivo combination study demonstrate the advantages of targeting CD73 and A2AR. We have obtained active molecules illustrated by in vitro data on primary human T lymphocytes. These results, have paved the way to an optimized process to identify adenosinergic pathway inhibitors with properties optimized for immuno-oncology. Citation Format: Pierre Fons, Michael Esquerré, Stéphanie Versluys, Gigliola Mambrini, Michael Paillasse, Andy Bell, Adrian Schreyer, Richard Cox, Richard Bickerton, Joanna Lisztwan, Mark Whittaker, Françoise Bono, Craig Johnstone, Andrew Hopkins. Targeting the adenosine immunosuppressive pathway for cancer immunotherapy with small molecule agents [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3970. doi:10.1158/1538-7445.AM2017-3970