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FOGHORN THERAPEUTICS Foghorn Therapeutics Provides Third Quarter 2021 Corporate Update November 9 , 2021 -- First patient dosed in phase 1 clinical trial of FHD - 609 , a potent and selective heterobifunctional protein degrader of BRD9 , initially being developed for the treatment of synovial sarcoma -- · Continue to enroll patients in phase 1 clinical trials of FHD - 286 , an inhibitor of BRG1 / BRM , in metastatic uveal melanoma and relapsed or refractory acute myeloid leukemia ( AML ) -- Presented an overview of Company's proprietary protein degrader platform and clinical stage asset , FHD - 609 , at the 4th Annual Targeted Protein Degradation Summit -- Continued advancement of broad therapeutic pipeline that includes protein degraders , enzymatic inhibitors and transcription factor disruptors targeting cancers impacted by breakdowns in the chromatin regulatory system CAMBRIDGE , Mass . , Nov. 09 , 2021 ( GLOBE NEWSWIRE ) -- Foghorn Therapeutics Inc. ( Nasdaq : FHTX ) , a clinical stage biotechnology company pioneering a new class of medicines that modulate gene expression through selectively targeting the chromatin regulatory system , today provided a corporate update in conjunction with the Company's 10 - Q filing for the quarter ended September 30 , 2021. With an initial focus in oncology , Foghorn's Gene Traffic Control PlatformⓇ and resulting broad pipeline has the potential to transform the lives of people suffering from a wide spectrum of diseases . " During the third quarter of 2021 , we continued to advance our robust pipeline targeting the chromatin regulatory system , " said Adrian Gottschalk , President and Chief Executive Officer . “ In August , we dosed the first patient in the phase 1 study of FHD - 609 , our potent , selective , intravenous , small molecule protein degrader of BRD9 , initially being developed for the treatment of synovial sarcoma . We continue to enroll patients in the phase 1 studies of FHD - 286 , an inhibitor of BRG1 / BRM being studied in metastatic uveal melanoma and relapsed or refractory AML and MDS , areas of high unmet medical need . These studies are progressing through dose escalation , and we are pleased with the execution of the enrollment to date and look forward to sharing initial data from these studies in the future . " Continued Mr. Gottschalk , " Beyond these two clinical programs , we continue to expand our deep pipeline of precision therapeutic candidates targeting different aspects of the chromatin regulatory system in cancer , including enzymatic inhibitors , transcription factor disruptors and over eight protein degrader programs such as our BRM - selective degrader , ARID1B degrader and other undisclosed programs . " Recent Corporate Highlights : • Dosed First Patient with FHD - 609 . In August , Foghorn announced the dosing of the first patient in its first - in - human clinical trial of FHD - 609 . FHD - 609 is a highly potent , selective , intravenous , protein degrader of BRD9 , initially being developed for the treatment of synovial sarcoma with the intention to expand into additional indications , including SMARCB1 deleted tumors . Sites for the phase 1 study have been activated and are currently dosing patients . To learn more about this study , please visit ClinicalTrials.gov . • Participation at the 4th Annual Targeted Protein Degradation Conference . In October 2021 , Foghorn presented at the 4th Annual Targeted Protein Degradation Conference providing an overview of the Company's degrader capabilities and its phase 1 asset FHD - 609 , including the programs compelling in - vitro and in - vivo profile supporting first - in - human studies . Within Foghorn's degrader platform , the Company is actively advancing more than eight targeted protein degrader programs including its BRM - selective degrader for BRG1 mutated cancers and its selective ARID1B program for ARID1A mutated cancers which impacts more than 175,000 patients a year . Additional information on the Summit can be found here . Key Upcoming Milestones : • FHD - 286 data . Foghorn expects to have initial data from the Company's phase 1 studies of FHD - 286 in both metastatic uveal melanoma and relapsed / refractory AML and MDS as early as the fourth quarter of 2021 . • FHD - 609 data . Foghorn expects to have initial data from the Company's phase 1 study in synovial sarcoma as early as the first half of 2022 . Upcoming Events • 4th Annual Evercore ISI HealthCONx Conference , November 30th - December 2nd , 2021 Financial Condition Foghorn reported cash , cash equivalents and marketable securities of $ 120.8 million as of September 30 , 2021 , as compared to $ 141.3 million as of June 30 , 2021 , and $ 185.8 million as of December 31 , 2020 . About Foghorn Therapeutics