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iTeos TM Therapeutics iTeos Reports Third Quarter 2021 Financial Results and Provides Corporate Updates November 10 , 2021 - First patients dosed in clinical trial of anti - TIGIT monoclonal antibody , EOS - 448 , in combination with pembrolizumab and with inupadenant in patients with solid tumors - Advanced clinical development of inupadenant , EOS - 850 , an A2A receptor antagonist , with initiation of an expansion in PD - 1 resistant melanoma in combination with pembrolizumab as well as a planned study further exploring novel predictive biomarkers - Received full upfront payment of $ 625MM at closing of development and commercialization collaboration agreement with GSK for EOS - 448 - Cash balance of $ 899.8MM as of September 30 , 2021 , providing runway into 2026 to support clinical development plans for EOS - 448 and inupadenant and growing pipeline of preclinical programs - Company to host conference call today at 4:30 p.m. ET CAMBRIDGE , Mass . and GOSSELIES , Belgium , Nov. 10 , 2021 ( GLOBE NEWSWIRE ) -- iTeos Therapeutics , Inc. ( Nasdaq : ITOS ) , a clinical - stage biopharmaceutical company pioneering the discovery and development of a new generation of highly differentiated immuno - oncology therapeutics for patients , today reported financial results for the third quarter ended September 30 , 2021 and provided recent business highlights . " We continued to make significant clinical progress advancing our next - generation immunotherapies in multiple cancer indications . We officially closed our transformational collaboration with GSK , allowing us to initiate novel immunotherapy combinations with the potential to improve outcomes for patients . This includes pairing GSK's recently approved anti - PD - 1 , Jemperli ( dostarlimab ) with our anti - TIGIT monoclonal antibody , EOS - 448 , and with both EOS - 448 and our highly differentiated clinical - stage A2A adenosine receptor antagonist , inupadenant , " said Michel Detheux , Ph.D. , president and chief executive officer of iTeos . " We are pleased to have started executing our accelerated clinical development plans , initiating dosing in cohorts evaluating EOS - 448 in combination with pembrolizumab and with inupadenant . We have also begun dosing patients with PD - 1 resistant melanoma in a trial evaluating inupadenant plus pembrolizumab . We remain focused on converting our scientific innovation into improved clinical outcomes for patients and plan to initiate multiple trials of additional combinations in the coming months . " Program Highlights EOS - 448 : IgG1 anti - TIGIT monoclonal antibody designed to engage the Fc gamma receptor ( FcyR ) and to enhance the anti - tumor response through a multifaceted mechanism . • In July 2021 , iTeos closed its development and commercialization collaboration agreement with GSK for EOS - 448 which was first announced in June 2021. iTeos received the full $ 625 million upfront payment and is eligible to receive up to $ 1.45 billion in potential milestone payments upon the achievement of certain development and commercial milestones as part of the agreement . • iTeos and GSK are advancing various novel combinations of potential next generation immuno - oncology agents . Two trials will be initiated in the coming months . The first , assessing the doublet of GSK's anti - PD - 1 , ( dostarlimab ) , with EOS - 448 and the second , a triplet of this combination adding inupadenant . • In September , iTeos dosed the first patients in a clinical trial of EOS - 448 in combination with pembrolizumab and in combination with inupadenant in patients with solid tumors . • The company will initiate a clinical trial in the first quarter of 2022 evaluating EOS - 448 as both a monotherapy and in combination with Bristol Myers Squibb's iberdomide in patients with multiple myeloma . Inupadenant ( EOS - 850 ) : Designed as an insurmountable and highly selective small molecule antagonist of the adenosine A2A receptor , the only high - affinity adenosine receptor expressed on different immune cells found in the tumor micro - environment . • iTeos has completed patient enrollment in the cohort evaluating the safety of inupadenant in combination with chemotherapy and with pembrolizumab as well as the monotherapy expansion cohort in prostate cancer . • The company has initiated an expansion cohort evaluating inupadenant in combination with pembrolizumab in patients with PD - 1 - resistant melanoma . • Based on results presented at ASCO in June 2021 , demonstrating that A2A receptor expression is associated with clinical outcomes in patients with solid tumors treated with single agent inupadenant , iTeos plans to explore a patient selection