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iTeos Therapeutics TM iTeos Reports Second Quarter 2021 Financial Results and Provides Business Update August 12 , 2021 • Announced co - development and co - commercialization collaboration with GSK for anti - TIGIT monoclonal antibody EOS - 448 ( GSK'859 ) ; $ 625MM upfront payment in addition to $ 1.45B in potential milestones , 40/60 cost - sharing of global development , 50/50 profit share in the US , and royalty payments on ex - US sales • Presented initial clinical data for EOS - 448 at AACR 2021 demonstrating target engagement , promising early monotherapy anti - cancer activity and tolerability at all dose levels • Updated data from Phase 1 / 2a trial of inupadenant ( EOS - 850 ) presented at ASCO 2021 show evidence of durable monotherapy anti - cancer activity , and a correlation between the expression of A2AR and clinical outcomes • Cash balance of $ 302.9MM as of June 30 , 2021 ; Subsequent to June 30 , received $ 625MM upfront payment from GSK , providing cash runway into 2026 • Company to host conference call today at 8:00 am ET CAMBRIDGE , Mass . and GOSSELIES , Belgium , Aug. 12 , 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 second quarter ended June 30 , 2021 and provided recent business highlights . " The last few months have been a transformative time for iTeos , as we achieved significant milestones that will shape the future of our company and help us in our mission to discover , develop and deliver therapies that will improve the lives of people with cancer . I am incredibly proud of our continued execution with our clinical programs and strategic initiatives , " said Michel Detheux , PhD , president , and chief executive officer of iTeos . " For our TIGIT program , we announced a transformational strategic collaboration with GSK that will allow us to combine our resources and expand and accelerate the development program for EOS - 448 through rapid evaluation of dostarlimab and triplet combinations beginning in the coming months . With the rights iTeos retained , we can maximize the value of EOS - 448 for patients and our shareholders . In addition to expanding our TIGIT program , the GSK collaboration is also an important validation for our team's ability to identify and pursue best - in - class anti - tumor drug candidates . To that end , we are excited to advance inupadenant , our second clinical - stage program , which has demonstrated in a Phase 1 trial durable responses in two patients with checkpoint inhibitor resistant tumors , good tolerability and a potentially predictive biomarker which will help to drive tumor and patient selection in upcoming trials . In the coming months , we look forward to advancing inupadenant into proof - of - concept trials in several indications . " Program Highlights EOS - 448 : IgG1 anti - TIGIT monoclonal antibody designed to engage the Fc gamma receptor ( FcyR ) and to enhance anti - tumor responses through a multifaceted mechanism of action . • In June 2021 , iTeos and GSK announced an agreement to co - develop and co - commercialize EOS - 448 . As part of the agreement , iTeos received a $ 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 . GSK is responsible for 60 % of expense in the global development plan . The companies will co - commercialize and equally split profits in the U.S. iTeos will be eligible to receive royalties on sales outside of the U.S. • In April 2021 , the Company presented initial clinical and safety data from the monotherapy dose escalation part of the Phase 1 trial in adult patients with advanced solid tumors at the American Association for Cancer Research ( AACR ) Annual Meeting . These preliminary data show the drug was well - tolerated across dose levels , caused depletion of TIGIT- expressing Treg cells in the blood , providing evidence of target and FcyR engagement , and had encouraging early signs of anti - cancer activity in Phase 1 , including one partial response in a pembrolizumab - resistant metastatic melanoma patient . • The Company is working with GSK to rapidly initiate trials of EOS - 448 in combinations including with Jemperli ( dostarlimab ) . • iTeos will also advance EOS - 448 in combination with pembrolizumab and with inupadenant in patients with solid tumors , and as a monotherapy and in combination with an Immunomodulatory Drug ( IMiD ) 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