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Generation Bio Presents Preclinical Data Demonstrating Broad Potential of Gene Therapy Platform at ASGCT and Reports First Quarter Financial Results Durable , therapeutically relevant levels of anti - SARS - CoV - 2 spike antibodies produced from the liver in a mouse model Next - generation rapid enzymatic synthesis of closed - ended DNA further increases the efficiency and scale of the manufacturing platform Potent factor VIII construct optimized by taking advantage of the increased cargo capacity of closed - ended DNA -- CAMBRIDGE , MASS . , May 12 , 2021 Generation Bio Co. ( Nasdaq : GBIO ) , an innovative genetic medicines company creating a new class of non - viral gene therapy , today reported data from multiple digital presentations during the ongoing 24th American Society of Gene and Cell Therapy ( ASGCT ) Annual Meeting as well as first quarter 2021 financial results . gene " We are excited to highlight two significant new developments for our novel , non - viral therapy platform that showcase its potential to address a broad range of diseases at a manufacturing scale unprecedented for gene therapy , ” said Geoff McDonough , M.D. , president and chief executive officer of Generation Bio . “ We have long thought that therapeutic antibodies could be produced by the liver , potentially expanding the durability and reach for certain classes of biologics . Our data demonstrate endogenous therapeutic antibody production from the livers of mice for anti - SARS - CoV - 2 spike antibodies . Combining these data with our proprietary rapid enzymatic synthesis method for closed - ended DNA ( ceDNA ) could open the door to address a number of highly prevalent infectious diseases . 2021 is set to be milestone - rich for the company , and we remain on track to execute our goals for the year . " Highlights from Digital Presentations at ASGCT • Novel non - viral gene therapy unlocks significant potential for genetic medicine : In a digital presentation entitled “ Non - Viral Gene Delivery of Human FVIII to Hemophilia A Mice and Non - Human Primates , ” the company presented insights into the scientific breakthroughs underpinning its unique non - viral approach , specifically the on - target biodistribution of its cell - targeted lipid nanoparticle ( ctLNP ) and the access to the nucleus afforded by ceDNA . To view the digital presentation , please visit Generation Bio's website . • Durable expression of therapeutically relevant levels of anti - SARS - CoV - 2 spike monoclonal antibody ( mAb ) expressed from the liver in mice : Building on its core technologies , Generation Bio has designed a ceDNA - based approach to generate persistent expression of therapeutic antibodies from the liver . Endogenous therapeutic antibody production may provide an alternative means of delivering specific mAbs , equipping patients with the ability to produce their own biotherapeutics for an extended 1