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SOLID BIOSCIENCES Solid Biosciences Provides Third Quarter 2021 Business Update and Financial Results November 3 , 2021 - Continued focus on advancing SGT - 001 includes additional patient dosings in IGNITE DMD expected to begin in Q4 2021 - - Continued progress with SGT - 003 ; Solid's next - generation Duchenne gene therapy program demonstrates enhanced muscle tropism and microdystrophin expression - - Company ends Q3 with approximately $ 229.8 million in cash and investments ; cash runway into Q2 2023 - CAMBRIDGE , Mass . , Nov. 03 , 2021 ( GLOBE NEWSWIRE ) -- Solid Biosciences Inc. ( Nasdaq : SLDB ) , a life sciences company focused on advancing meaningful therapies for Duchenne muscular dystrophy ( Duchenne ) , today provided a business update as well as financial results for the third quarter ended September 30 , 2021 . " Solid made progress across all its strategic priorities during the third quarter . We expect to dose additional patients in IGNITE DMD beginning in the fourth quarter of 2021. We also shared meaningful clinical data across a variety of endpoints from the ongoing IGNITE DMD clinical trial of SGT - 001 , which continue to guide our understanding of the potentially differentiated benefit that SGT - 001 may offer to patients . In addition , we advanced our Duchenne pipeline program , SGT - 003 , including selecting a manufacturing approach that will allow us to quickly move into human proof of concept in early 2023 , " said llan Ganot , Chief Executive Officer , President and Co - Founder of Solid Biosciences . " As we prepare to dose additional patients in IGNITE DMD , we enter the fourth quarter with a great deal of excitement and momentum around our opportunities to improve outcomes for patients with Duchenne . " SGT - 001 Update Solid expects to dose additional patients in IGNITE DMD , beginning in the fourth quarter of 2021. In addition , the company expects to report 90 - day biopsy data from the first three patients dosed with SGT - 001 manufactured with its improved process as well as long - term expression and functional data in early 2022. Concurrent with activities to support continued patient dosing in IGNITE DMD , Solid is also engaged in a variety of activities to support continued advancement of SGT - 001 , including scaling its improved manufacturing process . In September 2021 , the Company reported 1.5 - year data from IGNITE DMD at the World Muscle Society 2021 Virtual Congress and additional pulmonary function results from IGNITE DMD at the Child Neurology Society 50th Annual Meeting . Patients dosed with SGT - 001 exhibited sustained benefit across all reported measures over a period when natural history would suggest a decline . Solid is taking a leading role in reporting long - term respiratory data showcasing stability or improvement in pulmonary function across forced vital capacity , peak expiratory flow and forced expiratory volume in one second , important measures in the progression of Duchenne in patients . These data continue to suggest SGT - 001 is providing benefit to dosed patients . R & D Pipeline Update SGT - 003 , Solid's next - generation adeno - associated virus ( AAV ) capsid pipeline program , continued its progress during the third quarter and continues to demonstrate enhanced muscle tropism and microdystrophin expression in preclinical studies . Biodistribution data show increased vector genomes in muscle and heart as well as decreased vector genomes in liver with SGT - 003 compared to AAV9 in various in vitro and in vivo models . This biodistribution profile has the potential to increase efficiency and specifically target muscle cells , which could potentially allow for a reduced total viral load . As announced last month , Solid has entered into an agreement with Forge Biologics to advance the development and manufacturing of SGT - 003 using a transient transfection process . Solid is working closely with Forge to advance manufacturing of SGT - 003 and is looking toward a target IND filing in early 2023 . Solid also continued its progress with Ultragenyx on the companies ' collaboration that leverages Solid's proprietary nNOS - containing microdystrophin construct with an AAV8 - like capsid within Ultragenyx's HeLa producer cell line manufacturing approach . A program update is expected before the end of 2021 . Recent Company Developments Solid , in collaboration with REGENXBIO formally launched the Pathway Development Consortium ( PDC ) , a multistakeholder initiative which aims to identify , develop , expand and maintain pathways to effective therapies for patients diagnosed early in life with rare diseases . The PDC seeks to achieve these goals by bringing together a broad and diverse group of stakeholders from the rare disease and AAV gene therapy communities , including patients , industry , regulators , academia and payers , among others , for meaningful scientific and policy discussions . Financial Highlights Collaboration revenue for the third quarter of 2021 was $ 3.5 million , compared to no collaboration revenue for the third quarter of 2020. The increase in collaboration revenue is related to research services and cost reimbursement from our Collaboration Agreement with Ultragenyx , which the Company entered into in the fourth quarter of 2020 . Research and development expenses for the third quarter of 2021 were $ 14.4 million , compared to $ 16.0 million for the third quarter of 2020. The decrease was primarily related to lower manufacturing expenses for our lead product , SGT - 001 , offset by an increase in clinical and other R & D costs . General and administrative expenses for the third quarter of 2021 were $ 7.1 million , compared to $ 5.2 million for the third quarter of 2020. The increase was primarily attributable to increased corporate and personnel - related expenses .