Limb-Girdle Muscular Dystrophy, Type 2C

Participation in Chardan’s 7th Genetic Medicines Conference Participation in Cell and Gene Therapy on the Mesa 2023 Meeting Five upcoming communications on LGMD programs at WMS congress, ESGCT annual meeting and 2023 International Limb-Girdle Muscular Dystrophy Conference EVRY, France--(BUSINESS WIRE)-- Atamyo Therapeutics, a biotechnology company focused on the development of new-generation gene therapies targeting neuromuscular disease, today announced its participation to forthcoming conferences and scientific communications on its programs targeting limb-girdle muscular dystrophies (LGMDs). Atamyo to participate in Chardan's 7th Annual Genetic Medicines Conference and in Cell & Gene Meeting on the Mesa 2023 Stephane Degove, Atamyo CEO, will provide a corporate overview at two forthcoming conferences in October: • Chardan's 7th Annual Genetic Medicines Conference, held in New York City: - Presentation on October 2, at 10:30 AM, in the Embassy room • Cell & Gene Meeting on the Mesa, held in Carlsbad, CA, on October 10-12, 2023: - Presentation on October 10, at 5:15pm, at the Rentschler ATMP Ballroom Two upcoming communications at the 28th Annual Congress of the World Muscle Society (3-7 October 2023 in Charleston, SC) Two communications describing Atamyo’s LGMD programs will be presented at the 28th International Annual Congress of the World Muscle Society (WMS): 1) Evaluation of gene transfer efficiency in a mild model of dystrophic muscle disorder performed by machine learning and linear discriminant analysis • Oral Presentation by A. Brureau (Genethon), at Ballroom C2 on October 4, 2023 from 18h15 to 18h45 • Poster Board Number 282 at Ballroom C, on October 4, 2023, 17h15-18h15 2) Natural history of limb girdle muscular dystrophy R9: one-year follow-up of a European cohort • Oral Presentation by J. Vissing (Copenhagen Neuromuscular Center, Rigshospitale) at Ballroom C2 on October 4, 2023 from 18h15 to 18h45 • Poster Board Number 283 at Ballroom C, on October 4, 2023, 17h15-18h15 Two upcoming communications at the European Society of Gene & Cell Therapy 30th annual congress (24-27 October 2023 in Brussels - Belgium): Two communications describing Atamyo’s LGMD programs will be presented at the 30th Annual Congress of the European Society of Gene & Cell Therapy (ESGCT) that will take place on October 24-27, 2023 in Brussel (Belgium): 1) Gene therapy for LGMDR9: preliminary results of a dose-escalation study • Oral presentation by Nicolai Preisler, MD, Rigshospitalet, Copenhagen, during the Cardiovascular and muscular diseases session, on Friday October 27, 11h30-13h00 – Le BEL, Tour & Taxis 2) A micro-RNA regulated AAV vector prevents the cardiotoxicity induced by transgene overexpression following FKRP gene transfer • E. Gicquel (Genethon) et al., poster number P060, poster sessions October 25 and 26 Oral presentation on Atamyo’s LGMD-R9 program at the 2023 International Limb-Girdle Muscular Dystrophy Conference (28-29 October 2023, Washington DC) 1) Preliminary experiences with Atamyo’s FKRP gene therapy • Oral presentation by John Vissing, MD, Rigshospitalet, Copenhagen, during the Clinical Trials Updates (Part 1) Session, on October 29, 11h00am-12h10pm – Constitution Ballroom, Grand Hyatt About Atamyo Therapeutics Atamyo Therapeutics is a clinical-stage biopharma focused on the development of a new generation of effective and safe gene therapies for neuromuscular diseases. A spin-off of gene therapy pioneer Genethon, Atamyo leverages unique expertise in AAV-based gene therapy and muscular dystrophies from the Progressive Muscular Dystrophies Laboratory at Genethon. Atamyo’s most advanced programs address different forms of limb-girdle muscular dystrophies (LGMD), with two clinical-stage programs targeting respectively LGMD-R9 and LGMD-R5. The name of the company is derived from two words: Celtic Atao which means “Always” or “Forever” and Myo which is the Greek root for muscle. Atamyo conveys the spirit of its commitment to improve the life of patients affected by neuromuscular diseases with life-long efficient treatments. For more information visit View source version on businesswire.com: Contacts U.S. Contact: Charles Craig, Opus Biotech Communications charles.s.craig@gmail.com, 404-245-0591 European contact: contact@atamyo.com Source: Atamyo Therapeutics View this news release online at:

A multicenter phase 1b study will evaluate safety, pharmacodynamic and efficacy of ATA-200 ATA-200 is the second Atamyo’s next generation gene replacement therapy entering the clinic ATA-200 is eligible to receive up to €8m ($8.6m) of non-dilutive financing from France 2030 program EVRY, France--(BUSINESS WIRE)-- Atamyo Therapeutics, a biotechnology company focused on the development of new-generation gene therapies targeting neuromuscular diseases, today announced the filing of a Clinical Trial Application (CTA) in Europe for ATA-200, its gene therapy targeting γ-sarcoglycan (SGCG) related limb-girdle muscular dystrophy Type 2C/R5 (LGMD2C/R5). The company also announced that ATA-200 has been granted a non-dilutive financing up to €8m ($8.6m) from France 2030 public program managed by Bpifrance, to support its clinical trials and manufacturing development programs. This clinical trial (EUCT 2023-506440-16-00) is a multicenter, Phase 1b, open-label, dose escalation study evaluating safety, pharmacodynamic, efficacy, and immunogenicity of intravenous ATA-200, a single-dose Adeno-Associated Virus (AAV) vector carrying the human γ-sarcoglycan transgene. “LGMD-R5 is the most rapidly progressive and debilitating form of LGMDs with onset of symptoms in early childhood, a loss of ambulation before adulthood, and frequent cardiac impairment. No curative treatment exists for this disease,” said Dr Sophie Olivier, Chief Medical Officer of Atamyo. “ATA-200 incorporates a new promoter that enhances the liver and cardiac safety of gene therapy,” said Isabelle Richard, Ph.D., Co-founder and Chief Scientific Officer of Atamyo. “This first-in-class experimental treatment represents a new hope for the patients.” “We are thrilled to European Clinical trial and to receive such a strong public financing for the devastating LGMD2C/R5 disease,” said Stephane Degove, Co-Founder and Chief Executive Officer of Atamyo. “With the ongoing clinical trial in LGMD-R9, the initiation of the clinical program for LGMD-R5/2C confirms our unique capabilities in bringing to patients suffering from limb-girdle muscular dystrophies a new generation of safe and effective gene therapies.” LGMD2C/R5 is a rare genetic disease caused by mutations in the gene that produces γ-sarcoglycan, a transmembrane protein that is involved in the connection between muscle fibers and their environment. It affects an estimated 2,000 people in Europe only. In the classical form, symptoms appear in early childhood and patients suffer from progressive muscular weakness leading to loss of ambulation before adulthood. Cardiac involvement, typically presenting as dilated cardiomyopathy is reported in approximately half of patients. There is no curative treatment. The management of LGMDR5 is solely supportive. ATA-200, the gene therapy for LGMD2C/R5, delivers a normal copy of the gene for production of γ-sarcoglycan. In preclinical mice models, ATA-200 demonstrated its tolerability and capability to correct symptoms and biomarkers of the pathology. Atamyo plans to initiate dosing in patients for ATA-200 in the first half of 2024. In addition to its LGMD2C/R5 gene therapy, Atamyo is developing a clinical trial with ATA-100 gene therapy for LGMD2I/R9, related to deficiencies in FKRP; and is in IND-enabling studies for LGMD2A/R1, related to deficiencies in calpain protein. About Atamyo Therapeutics Atamyo Therapeutics is a clinical-stage biopharma focused on the development of a new generation of effective and safe gene therapies for neuromuscular diseases. A spin-off of gene therapy pioneer Genethon, Atamyo leverages unique expertise in AAV-based gene therapy and muscular dystrophies from the Progressive Muscular Dystrophies Laboratory at Genethon. Atamyo’s most advanced programs address different forms of limb-girdle muscular dystrophies (LGMD), with two clinical-stage programs targeting respectively LGMD-R9 and LGMD-R5. The name of the company is derived from two words: Celtic Atao which means “Always” or “Forever” and Myo which is the Greek root for muscle. Atamyo conveys the spirit of its commitment to improve the life of patients affected by neuromuscular diseases with life-long efficient treatments. For more information visit About France 2030 Launched by the President of France Republic in October 2021, France 2030 is a €54 ($58) billion program which aims to accelerate the transformation of key sectors of the French economy through innovation. From fundamental research, emergence of an idea, and up to the production of a new product or service, France 2030 supports the entire life cycle of innovation until its industrialization. More information on : france2030.gouv.fr View source version on businesswire.com: Contacts U.S. Contact: Charles Craig, Opus Biotech Communications charles.s.craig@gmail.com, 404-245-0591 European contact: contact@atamyo.com Source: Atamyo Therapeutics View this news release online at:

EVRY, France--(BUSINESS WIRE)-- Atamyo Therapeutics, a biotechnology company focused on the development of new-generation gene therapies targeting neuromuscular diseases, today announced multiple major milestones for ATA-100 and ATA-200, its one-time gene-replacement therapies for the treatment of limb-girdle muscular dystrophy types 2I/R9 and 2C/R5 (LGMD2I/R9 and LGMD2C/R5 respectively), as well as the reinforcement of its management team. Authorization of Clinical Trial Application in France for ATA-100 A third authorization of a Clinical Trial Application (CTA) in Europe was granted by the French National Medicines Health Agency (ANSM) for ATA-100. Two CTA approvals had previously been granted respectively by the United Kingdom Medicines & Healthcare products Regulatory Agency (MHRA) and by the Denmark Danish Medicines Agency (DKMA). ATA-100, a single-administration gene therapy candidate for LGMD2I/R9, delivers a normal copy of the gene for production of FKRP proteins. LGMD2I/R9 is a rare genetic disease caused by mutations in the gene that produces fukutin-related protein (FKRP) and affects an estimated 5,000 people in the US and Europe. Orphan Drug Designation awarded from European EMA for ATA-200 ATA-200, Atamyo’s one-time gene replacement therapy for the treatment of LGMD 2C/R5, has been granted Orphan Drug Designation by the European Medicines Agency (EMA) for the treatment of LGMD. Orphan Drug Designations by the EMA grants a ten-year market exclusivity in Europe and provides with other benefits such as tax credits, protocol assistance and research grants. The therapy is based on the research of Atamyo Chief Scientific Officer Isabelle Richard, Ph.D., Research Director at CNRS who heads the Progressive Muscular Dystrophies Laboratory at Genethon. “We are thrilled by this additional approval for our first-in-human trial with ATA-100 and by the Orphan Drug Designation in Europe for ATA-200. These single-administration treatments bring hope to patients with LGMD2I/R9 and LGMD2C/R5,” said Stéphane Degove, CEO of Atamyo Therapeutics. Forthcoming presentation of ATA-200 at ASGCT annual meeting on May 16, 2022 The ATA-200 construct, as well as unveiled in vivo results and GLP-biodistribution and toxicology study, will be presented at the forthcoming ASGCT 25th Annual Meeting, Washington (DC) on May 16-19, 2022. The poster presentation details are: Abstract #173 and Poster Board Number M-54: Preclinical Development of a Gene Therapy for Gamma Sarcoglycanopathy, J Poupiot et al. Session Title: AAV Vectors - Preclinical and Proof-of-concept Studies I Location, Date and Start Time: Hall D – May 16, 2022 17:30 (EST) “We are looking forward to presenting to the community ATA-200/GNT008 our first-in-class one-time gene replacement therapy for LGMD2C/R5,” said Isabelle Richard, Chief Scientific Officer at Atamyo Therapeutics. LGMD 2C/R5 affects an estimated 2,000 people in the US and Europe. Symptoms usually appear during early childhood. Patients suffer from progressive muscular weakness leading to loss of ambulation before adulthood. They also are prone to respiratory impairment and myocardial dysfunction. There are currently no curative treatments for LGMD2C/R5. Appointment of Catherine Cancian MSc, MEng, MBA, as CTO Atamyo also announced the appointment of Ms. Catherine Cancian, MSc, MEng, MBA as Chief Technical Officer overseeing all pharmaceutical development, clinical and future commercial supply. Ms Cancian has an extensive career as a senior manager in the industry, particularly in regard to pharmaceutical development of biologicals. Before joining Atamyo, Ms. Cancian was Vice President Pharmaceutical Operations for GenSight Biologics where she developed and executed the strategy for CMC and Supply Chain activities to support the clinical development and commercial readiness of AAV-based gene therapies. Previously, Catherine was Industrialization Project Director for the setup of a new Gene and Cell Therapy manufacturing facility at YposKesi and served at Sanofi Pasteur during 18 years at various management positions including Manufacturing, Project Management, Process Science & Technology and Quality for various marketed vaccines. About Atamyo Therapeutics Atamyo Therapeutics is focused on the development of a new generation of effective and safe gene therapies for neuromuscular diseases. A spin-off of gene therapy pioneer Genethon, Atamyo leverages unique expertise in AAV-based gene therapy and muscular dystrophies from the Progressive Muscular Dystrophies Laboratory at Genethon. Atamyo’s most advanced programs address different forms of limb-girdle muscular dystrophies (LGMD). The name of the company is derived from two words: Celtic Atao which means “Always” or “Forever” and Myo which is the Greek root for muscle. Atamyo conveys the spirit of its commitment to improve the life of patients affected by neuromuscular diseases with life-long efficient treatments. For more information visit www.atamyo.com.