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AVIDITY BIOSCIENCES Exhibit 99.1 Avidity Biosciences Reports Second Quarter 2021 Financial Results and Recent Highlights LA JOLLA , Calif . , Aug. 9 , 2021 / PRNewswire / -- Avidity Biosciences , Inc. ( Nasdaq : RNA ) , a biopharmaceutical company committed to delivering a new class of RNA therapeutics called Antibody Oligonucleotide Conjugates ( AOCSTM ) , today reported financial results for the second quarter and six months ended June 30 , 2021 and highlighted recent corporate progress . " The FDA clearance to proceed with our AOC 1001 Phase 1/2 MARINA ™ trial in adults with myotonic dystrophy ( DM1 ) is a huge milestone for Avidity and our AOC platform . AOC 1001 will be the first program based on our novel technology to enter clinical development . This also marks an important step forward for the DM1 community who have no approved therapies and so desperately needs therapeutic options , " said Sarah Boyce , president and chief executive officer . " In addition , over the past quarter we made significant advances in our pipeline including nominating AOC 1044 as the clinical development candidate for our lead DMD program . We remain on track for both AOC 1044 and our AOC FSHD program to advance into the clinic in 2022. " " We are well funded with $ 280 million at the end of Q2'21 , along with an additional $ 155 million in estimated net proceeds from our successful financing in August 2021. Our strong financial position allows us to further progress our late stage programs while continuing to invest in our skeletal muscle pipeline and our AOC platform , " said Mike MacLean , chief financial officer . AOC Platform and Pipeline Highlights • Received FDA clearance to proceed with clinical studies for AOC 1001 in adults with DM1 . 0 Avidity recently received clearance to proceed with the Phase 1/2 MARINA trial of AOC 1001 in adults with DM1 , under its Investigational New Drug application ( IND ) . Avidity continues to be on track to initiate the Phase 1/2 MARINA clinical trial this year . In the second half of 2022 , the Company plans to conduct a preliminary assessment of safety , tolerability and key biomarkers . O Detailed information on the MARINA study was presented during Volume 2 of Avidity's virtual investor and analyst event series . Volume 2 featured presentations on AOC 1001 , the MARINA study and a presentation on the clinical impact of DM1 by Nicholas E. Johnson , MD , MSCI , FAAN , an associate professor , division chief of neuromuscular , and vice chair of research in the department of neurology at Virginia Commonwealth University . The event also featured a live Q & A session with Avidity's management team and Dr. Johnson . Volume 2 in the series follows Volume 1 which was focused on the years of engineering underpinning Avidity's AOC platform and AOC 1001. Replays of Volume 1 and Volume 2 can be found on the events page in the investors section of the Avidity website . In July , the FDA granted Orphan Drug Designation for AOC 1001 for the treatment of DM1 . The FDA grants Orphan Drug Designation to novel drugs that seek to treat a rare disease or condition and , if the drug is approved for the designated orphan indication , provides 7 years of market exclusivity , along with certain financial incentives , including tax credits , opportunities for grant funding towards clinical trial costs and FDA user - fee waivers .