Abstract 353: Development of anin vitroscreening platform for high capacity evaluation of immunomodulatory drug candidates

Cancer immunotherapy has greatly expanded the therapeutic options against cancer. Recently approved antibody immunotherapies targeting immune-checkpoint molecules expressed on active T cells have shown promise in providing durable clinical anti-tumor responses in a substantial subset of melanoma and lung cancer patients. These clinical successes have prompted renewed efforts to identify efficacious approaches to harness the anti-tumor functions of the immune system. Combination immunotherapy that targets multiple immune-checkpoint molecules and/or combines immunotherapy and chemotherapy will likely lead to improved efficacy and reduced toxicity. A key challenge in immuno-oncology drug discovery is the lack of high throughput assay technologies to address the complexities of immune cell biology and drug screening. To address this, we have developed a robust and versatile in vitro T cell activation assay that leverages our well-established and validated high throughput combinatorial screening and data analysis platform. Our platform utilizes primary human peripheral T cells and measures a suite of T cell activation parameters including cell surface markers by high-throughput FACS, cytokines (e.g. IL-2, TNFα, IFNγ by HTRF or bead-based multiplexed technology, and proliferation by ATP, BrdU, or dye-based assays. Miniaturized to a 384-well format and supported by automation at each experimental step, including acoustic no-contact compound/antibody delivery, our assays are robust, exhibiting high Z’ values, high reproducibility between various donors and days of operation, and high capacity of up to twenty thousand data points per day. The platform is highly customizable in terms of testing agents that either enhance or inhibit CD3 or CD3/CD28-mediated T cell activation, including antibody drug candidates and/or small molecules while examining single agent dose responses and/or combination interactions, as well as accommodating varied dose schedules. Screening data is tracked through a proprietary laboratory information management system (LIMS) and analyzed by the state-of-the-art Horizon Chalice Analyzer software that applies the most appropriate synergy analysis for combination effects. Effect of reference immunomodulatory agents tested in this platform will be discussed. Finally, our high capacity technology platform is compatible with other cellular immunoassays such as the mixed lymphocytes reaction (MLR), NK cell-mediated antibody dependent cellular cytotoxicity (ADCC) assays, and T cell-mediated tumor cell lysis assays aided by engineered bispecific antibodies. We believe that this versatile high throughput immuno-oncology platform will enable large scale interrogation of prospective immunomodulatory agents, either alone or in combination, and thus contribute substantially to the discovery and development of future immunotherapies. Citation Format: Sujatha Kumar, Felicia Zhao, Anatoly Myaskovsky, Lydia Kifle, Nicola McCarthy, Jon Moore, Dennis France, Janine Steiger, W. Frank An. Development of an in vitro screening platform for high capacity evaluation of immunomodulatory drug candidates. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 353.