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EX - 99.12 dyn - ex991_6.htm EX - 99.1 YDyne THERAPEUTICS Exhibit 99.1 Dyne Therapeutics Reports Second Quarter 2021 Financial Results and Business Highlights - On Track to Submit INDs for DM1 , DMD and FSHD Programs Between the Fourth Quarter of 2021 and the Fourth Quarter of 2022 - - New In Vivo Data from DM1 and DMD Programs to be Presented at Scientific Meetings this Fall - WALTHAM , Mass . , August 5 , 2021 - Dyne Therapeutics , Inc. ( Nasdaq : DYN ) , a muscle disease company focused on advancing innovative life - transforming therapeutics for people living with genetically driven diseases , today reported financial results for the second quarter 2021 and business highlights . " We were pleased to present preclinical data from our DM1 and FSHD programs at scientific meetings during the quarter which further support our approach for addressing these devastating diseases , neither of which has any approved therapies , " said Joshua Brumm , president and chief executive officer of Dyne . " We remain on track to submit INDs for all three of our programs – DM1 , DMD and FSHD - between the fourth quarter of 2021 and the fourth quarter of 2022. We have an exceptional team and the right resources to transition Dyne into a clinical stage company focused on bringing potentially life - transforming therapies to patients . " Recent Highlights The Company presented preclinical data from its facioscapulohumeral muscular dystrophy ( FSHD ) program during the 28th Annual FSHD Society International Research Congress in June 2021. Data from in vitro studies in an FSHD patient cell line highlighted that Dyne's proprietary FORCE ™ platform enabled targeted muscle delivery with its lead FSHD candidate demonstrating potent suppression of DUX4 transcriptome markers . Oxana Beskrovnaya , Ph.D. , was appointed chief scientific officer in June 2021 , after serving as Dyne's senior vice president , head of research since January 2020 . The Company presented new preclinical data from its myotonic dystrophy type 1 ( DM1 ) program , during the American Society of Gene & Cell Therapy ( ASGCT ) 24th Annual Meeting in May 2021 . ○ о To assess the ability of its lead DM1 candidate to reduce toxic human nuclear DMPK RNA , Dyne developed an innovative hTfR1 / DMSXL mouse model that expresses the human TfR1 and carries a human DMPK gene that represents a severe DM1 phenotype with more than 1,000 CTG repeats . Dyne's lead DM1 candidate demonstrated sustained DMPK RNA knockdown at 4 weeks in multiple muscles after administration of a single , low 10 mg / kg dose . The Company also reported new in vitro findings from DM1 patient cells with approximately 380 and 2,600 CTG repeats , where its candidate showed a robust , dose- 1