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cogent BIOSCIENCES Cogent Biosciences Provides Corporate Updates and Reports Third Quarter 2021 Financial Results November 10 , 2021 Initiated SUMMIT , a Phase 2 clinical trial of bezuclastinib for Nonadvanced Systemic Mastocytosis ( NonAdvSM ) patients PEAK , a Phase 3 clinical trial of bezuclastinib and sunitinib for Gastrointestinal Stromal Tumor ( GIST ) patients , remains on track for 2021 start following positive FDA discussions Presented new preclinical data demonstrating bezuclastinib as a differentiated KIT inhibitor with minimal brain penetration Ended Q3 2021 with $ 202.9 million in cash , sufficient to fund operations into 2024 CAMBRIDGE , Mass . and BOULDER , Colo . , Nov. 10 , 2021 / PRNewswire / -- Cogent Biosciences , Inc. ( Nasdaq : COGT ) , a biotechnology company focused on developing precision therapies for genetically defined diseases , today announced financial results for the third quarter ended September 30 , 2021 and provided corporate updates . cogent BIOSCIENCES " We are pleased to announce that we have started the SUMMIT trial , a Phase 2 study of bezuclastinib in patients with nonadvanced systemic mastocytosis , " said Andrew Robbins , President and CEO of Cogent Biosciences . " Based on recently presented preclinical data , we believe that bezuclastinib has best - in - class potential as a highly potent and selective KIT mutant inhibitor and look forward to initiating the PEAK trial for GIST patients in the coming weeks . " Recent Program and Corporate Highlights • SUMMIT trial initiated in NonAdvSM patients • Cogent initiated SUMMIT , a randomized , double - blind , placebo - controlled , global , multicenter , Phase 2 clinical trial . The study is designed to explore the safety and efficacy of bezuclastinib in patients with moderate to severe Indolent Systemic Mastocytosis ( ISM ) or Smoldering Systemic Mastocytosis ( SSM ) . • SUMMIT is designed in three parts . Part 1 will enroll approximately 48 patients across 3 dose cohorts , plus one placebo arm , and is designed to confirm the optimal bezuclastinib dose . In addition , Part 1 will serve to validate a patient - reported outcomes ( PRO ) tool for use in assessing efficacy during Part 2 of the trial . Part 2 of SUMMIT will be randomized , double - blind , and placebo - controlled at a single dose level and will include a primary endpoint of disease improvement using the PRO tool from Part 1. After participation in Part 1 or Part 2 , all patients may receive bezuclastinib in a long - term extension . • Learn more about the SUMMIT trial at cogentclinicaltrials.com • APEX trial on track for preliminary clinical data readout in the first half of 2022 • Cogent is currently enrolling APEX , a Phase 2 clinical trial of bezuclastinib in patients with Advanced Systemic Mastocytosis ( AdvSM ) and expects to report preliminary clinical data at a scientific conference during the first half of 2022 , including levels of serum tryptase , a validated biomarker of mast cell activity . o Learn more about the APEX trial at cogentclinicaltrials.com . • PEAK trial of bezuclastinib and sunitinib for GIST patients to start in 2021 • Following recent positive interactions with the FDA , Cogent remains on track to initiate PEAK , a Phase 3 clinical trial of bezuclastinib in combination with sunitinib in imatinib - resistant GIST patients , during 2021 . • Announces updated bezuclastinib formulation in partnership with Serán Biosciences