DUX4

Biomarker cohort for delpacibart braxlosiran (del-brax), the first potential therapy to target DUX4, is measuring changes in DUX4 regulated biomarkers; del-brax 2 mg/kg will be administered every six weeks Enrollment in the del-brax biomarker cohort expected to be completed in 1H 2025; on track to initiate del-brax functional cohort in 1H 2025In previously reported initial data, del-brax 2 mg/kg every six weeks showed unprecedented and consistent reductions of DUX4 regulated genes, significant decreases in novel circulating biomarker and creatine kinase, and trends of functional improvement at the four-month timepoint SAN DIEGO, Oct. 30, 2024 /PRNewswire/ -- Avidity Biosciences, Inc. (Nasdaq: RNA), a biopharmaceutical company committed to delivering a new class of RNA therapeutics called Antibody Oligonucleotide Conjugates (AOCs™), today announced the initiation of a biomarker cohort in the Phase 1/2 FORTITUDE™ trial of delpacibart braxlosiran (del-brax/AOC 1020) in people living with facioscapulohumeral muscular dystrophy (FSHD). Avidity is pursuing a potential accelerated approval path for del-brax and expects enrollment in the biomarker cohort to be completed in the first half of 2025. Avidity also remains on track to initiate a functional cohort in the first half of 2025. In addition, enrollment of the FORTITUDE Open-label Extension study (OLE) is ongoing. Continue Reading (PRNewsfoto/Avidity Biosciences, Inc.) Del-brax is the first investigational therapy designed to treat the underlying cause of FSHD by directly targeting the disease-causing gene, double homeobox 4 (DUX4). Currently, there are no approved therapies for the treatment of FSHD, a rare, hereditary disorder marked by life-long, relentless loss of muscle function, significant pain, fatigue, and progressive disability. "The initiation of the biomarker cohort marks a key step in our strategy to pursue a potential accelerated approval path for del-brax, the first potential treatment to directly target the root cause of FSHD," said Steve Hughes, M.D., chief medical officer at Avidity. "We are very pleased with the del-brax 2 mg/kg data which showed unprecedented and consistent reductions of DUX4-regulated genes, significant decreases in novel circulating biomarker and creatine kinase, and trends of functional improvement with favorable safety and tolerability at the four-month timepoint. We are advancing our clinical studies for del-brax as quickly as possible as we understand the urgency to bring a potential new treatment to people living with FSHD who have no treatment options." The biomarker cohort in the FORTITUDE trial will assess the impact of del-brax 2 mg/kg every six weeks in people living with FSHD, ages 16-70. The primary endpoints of the study are changes in DUX4 regulated gene expression and DUX4 regulated circulating biomarker. For people living with FSHD it is important to maintain suppression of DUX4 at all times as aberrant gene expression is toxic to the muscles. Favorable safety and tolerability, as well as decreases in circulating biomarker and creatine kinase levels were similar for patients treated with 2mg/kg or 4mg/kg of del-brax. Due to this similarity, Avidity selected 2 mg/kg of del-brax to be administered every six weeks, designed to ensure continuous suppression of DUX4 for the biomarker and functional cohorts. In June of this year, Avidity reported positive initial del-brax 2 mg/kg data at four months from the Phase 1/2 FORTITUDE trial demonstrating unprecedented and consistent reductions of greater than 50% in DUX4 regulated genes, mean reductions of 25% or greater in novel circulating biomarker and creatine kinase, trends of functional improvement, and favorable safety and tolerability in people living with FSHD at the 31st Annual FSHD Society International Research Congress. About the Phase 1/2 FORTITUDE™ trial The FORTITUDE™ trial is a randomized, placebo-controlled, double-blind, Phase 1/2 clinical trial designed to evaluate single and multiple doses of delpacibart braxlosiran or del-brax (AOC 1020) in approximately 100 participants with facioscapulohumeral muscular dystrophy (FSHD). FORTITUDE will evaluate the safety, tolerability, pharmacokinetics, and pharmacodynamics of del-brax administered intravenously. Activity of del-brax will be assessed using key biomarkers, including DUX4-regulated muscle and circulating biomarkers and magnetic resonance imaging (MRI) measures of muscle volume and composition. Though the Phase 1/2 trial is not statistically powered to assess functional benefit, it will explore the clinical activity of del-brax including measures of mobility and muscle strength as well as patient reported outcomes and quality of life measures. Participants will have the option to enroll in FORTITUDE-OLE, an open-label extension study once participation in the FORTITUDE study is complete. For more information about the FORTITUDE trial, visit the FORTITUDE study website or visit and search for NCT05747924. About the Phase 2 FORTITUDE-OLE™ trial FORTITUDE-OLE™ is an open-label, multi-center trial designed to evaluate the long-term safety and tolerability of delpacibart braxlosiran or del-brax (AOC 1020) in participants with facioscapulohumeral muscular dystrophy (FSHD) who were previously enrolled in the FORTITUDE Phase 1/2 trial. This trial will continue to evaluate the safety, tolerability, PK, PD, and efficacy of del-brax in participants that enrolled in the randomized, placebo-controlled, Phase 1/2 FORTITUDE clinical trial. Participants who enroll in the FORTITUDE-OLE study will receive del-brax regardless of whether they received active treatment or placebo in the FORTITUDE study. The total duration of active treatment with del-brax in the FORTITUDE-OLE is approximately 24 months. Avidity may extend active treatment beyond 24 months at a future timepoint. For more information on the FORTITUDE-OLE study click here or visit and search for NCT06547216. About Del-brax (AOC 1020) Del-brax (AOC 1020) is designed to treat the underlying cause of FSHD, which is caused by the abnormal expression of a gene called double homeobox 4 or DUX4. The abnormal expression of DUX4 protein leads to changes in gene expression in muscle cells that are associated with the life-long, progressive loss of muscle function in patients with FSHD. Del-brax aims to reduce the expression of DUX4 mRNA and DUX4 protein in muscles in people with FSHD. Del-brax consists of a proprietary monoclonal antibody that binds to the transferrin receptor 1 (TfR1) conjugated with a siRNA targeting DUX4 mRNA. Avidity reported positive initial del-brax 2 mg/kg data at four months from the Phase 1/2 FORTITUDE trial demonstrating unprecedented and consistent reductions of greater than 50% in DUX4 regulated genes, trends of functional improvement, and favorable safety and tolerability in people living with FSHD. Del-brax is currently in Phase 1/2 development as part of the FORTITUDE™ trial in individuals with FSHD. The U.S. Food and Drug Administration (FDA) and the European Medicines Agency (EMA) have granted Orphan designation for del-brax and the FDA has granted del-brax Fast Track designation. About Facioscapulohumeral Muscular Dystrophy (FSHD) Facioscapulohumeral muscular dystrophy (FSHD) is a rare, progressive, and variable hereditary muscle-weakening condition marked by life-long, relentless loss of muscle function, significant pain, fatigue, and progressive disability. It is characterized by progressive and often asymmetric skeletal muscle loss that initially causes weakness in muscles in the face, shoulders, arms and trunk and progresses to weakness in muscles in the lower body. FSHD is an autosomal dominant disease caused by the aberrant expression of the DUX4 (double homeobox 4) gene in the skeletal muscle, which activates genes that are toxic to muscle cells and leads to a series of downstream events that result in skeletal muscle wasting and compromised muscle function. Skeletal muscle weakness results in physical limitations throughout the whole body, including an inability to lift arms for more than a few seconds, loss of ability to show facial expressions and serious speech impediments. These symptoms cause many people affected by FSHD to become dependent on the use of a wheelchair for mobility. Currently, there are no approved treatments for people living with FSHD. About Avidity Avidity Biosciences, Inc.'s mission is to profoundly improve people's lives by delivering a new class of RNA therapeutics - Antibody Oligonucleotide Conjugates (AOCs™). Avidity is revolutionizing the field of RNA with its proprietary AOCs, which are designed to combine the specificity of monoclonal antibodies with the precision of oligonucleotide therapies to address targets and diseases previously unreachable with existing RNA therapies. Utilizing its proprietary AOC platform, Avidity demonstrated the first-ever successful targeted delivery of RNA into muscle and is leading the field with clinical development programs for three rare muscle diseases: myotonic dystrophy type 1 (DM1), Duchenne muscular dystrophy (DMD) and facioscapulohumeral muscular dystrophy (FSHD). Avidity is broadening the reach of AOCs with its advancing and expanding pipeline including programs in cardiology and immunology through internal discovery efforts and key partnerships. Avidity is headquartered in San Diego, CA. For more information about our AOC platform, clinical development pipeline and people, please visit and engage with us on LinkedIn and X. Forward-Looking Statements Avidity cautions readers that statements contained in this press release regarding matters that are not historical facts are forward-looking statements. These statements are based on the company's current beliefs and expectations. Such forward-looking statements include, but are not limited to, statements regarding: the primary endpoints, design, goals and other details related to the FORTITUDE™ trial and each of its cohorts; the status and clinical development of del-brax, including any potential accelerated approval; Avidity's plans for the FORTITUDE-OLE™ study and the timing thereof; the characterization of safety, tolerability and functional data associated with del-brax from the Phase 1/2 FORTITUDE trial; the impact of such data on the advancement of del-brax; the plans and timing of adding a functional cohort for the FORTITUDE trial and the biomarker and functional cohorts potentially serving as the basis for registration; the potential of Avidity's product candidates to treat rare diseases and Avidity's efforts to bring them to people suffering from applicable diseases; and the potential of AOCs to target a range of different cells and tissues beyond the liver, and to treat cardiac and immunological diseases. The inclusion of forward-looking statements should not be regarded as a representation by Avidity that any of these plans will be achieved. Actual results may differ from those set forth in this press release due to the risks and uncertainties inherent in Avidity's business and those beyond its control, including, without limitation: preliminary results of a clinical trial are not necessarily indicative of final results and additional participant data related to del-brax that continues to become available may be inconsistent with the data produced as of the date hereof, and further analysis of existing data and analysis of new data may lead to conclusions different from those established as of the data cutoff; unexpected adverse side effects to, or inadequate efficacy of, Avidity's product candidates that may delay or limit their development, regulatory approval and/or commercialization, or may result in clinical holds which may not be timely lifted, recalls or product liability claims; Avidity's current and planned cohorts in the FORTITUDE trial may not support the registration of del-brax; Avidity is early in its development efforts; Avidity's approach to the discovery and development of product candidates based on its AOC platform is unproven, and the company does not know whether it will be able to develop any products of commercial value; potential delays in the commencement, enrollment, data readouts and completion of preclinical studies or clinical trials; Avidity's dependence on third parties in connection with preclinical and clinical testing and product manufacturing; regulatory developments in the United States and foreign countries; and other risks described in Avidity's Annual Report on Form 10-K for the fiscal year ended December 31, 2023, filed with the Securities and Exchange Commission (SEC) on February 28, 2024, and in subsequent filings with the SEC. Avidity cautions readers not to place undue reliance on these forward-looking statements, which speak only as of the date hereof, and the company undertakes no obligation to update such statements to reflect events that occur or circumstances that arise after the date hereof. All forward-looking statements are qualified in their entirety by this cautionary statement, which is made under the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. Investor Contact: Michael MacLean (619) 837-5014 [email protected] Media Contact: Navjot Rai (619) 837-5016 [email protected] SOURCE Avidity Biosciences, Inc. WANT YOUR COMPANY'S NEWS FEATURED ON PRNEWSWIRE.COM? 440k+ Newsrooms & Influencers 9k+ Digital Media Outlets 270k+ Journalists Opted In GET STARTED

– Company’s non-cutting technology, engineered to be even more compact and deliverable, demonstrates synergistic gene reactivation in vitro –SOUTH SAN FRANCISCO, Calif., Oct. 22, 2024 (GLOBE NEWSWIRE) -- Epicrispr Biotechnologies, a leading epigenetic editing company, presented new data on its hypercompact platform for epigenetic editing, in addition to IND-enabling data for its investigational therapy for facioscapulohumeral muscular dystrophy (FSHD), at the European Society of Gene and Cell Therapy (ESGCT) 31st Annual Congress taking place October 22-25, 2024, in Rome. Epicrispr plans to initiate clinical trials of lead candidate EPI-321 in early 2025. Among the data presented are results of in vitro studies of a novel epigenetic modulator for gene reactivation, developed through Epicrispr’s rational protein engineering. The ability to reactivate epigenetically silenced genes is critical to fulfilling the therapeutic potential of programmable epigenetic editing. Epicrispr’s data demonstrate that the new modulator can reactivate a silenced gene to near 100% expression, with durability of more than 75 days (over 150 cell divisions). Additionally, when the modulator is combined with the company’s previously reported epigenetic activators in a single construct, studies demonstrate powerful synergistic activity that substantially exceeds activation achieved with either component singly. This highlights the potential for GEMS therapeutics to robustly reactivate human genes to treat disease. Full details of the posters are as follows: Title: "Engineered ultracompact epigenetic editors for DNA and histone modifications enable durable epigenetic gene activation and suppression"Session: Poster Session IIIPresenter: Dan HartDate & Time: Thursday, October 24, 2:00-3:30 p.m. CESTPoster Number: P0523 Title: "Preclinical data supporting efficacy and safety of EPI-321, an investigational epigenetic editing product treating FSHD"Session: Poster Session IPresenter: Siddaraju BoregowdaDate & Time: Tuesday, October 22, 7:30 to 9:00 p.m. CESTPoster Number: P0263 Title: "Preclinical in vitro and ex vivo evaluation of EPI-321, an investigational single dose epigenome editing gene therapy, efficacy for facioscapulohumeral muscular dystrophy (FSHD) treatment"Session: Poster Session IVPresenter: Abhinav AdhikariDate & Time: Thursday, October 24, 6:00 to 7:30 p.m. CESTPoster Number: P0594 About EPI-321EPI-321 is an investigational epigenetic therapy that aims to address the underlying molecular mechanisms of FSHD by restoring methylation to the D4Z4 region of chromosome 4 and halting toxic expression of the DUX4 gene. EPI-321 is delivered to muscle tissue within a single AAV vector (AAVrh74) which has been clinically validated for muscle delivery. Preclinical studies on EPI-321 have demonstrated its ability to robustly suppress pathological expression of the DUX4 gene and reduce muscle cell death. About Epicrispr BiotechnologiesEpicrispr Biotechnologies is a leading epigenetic editing company, leveraging the power of CRISPR without cutting DNA. The company’s proprietary Gene Expression Modulation System (GEMS) includes the smallest Cas protein known to work in human cells, enabling in vivo or ex vivo delivery via a single viral vector. In addition to the lead program, EPI-321, additional programs seek to address alpha-1 antitrypsin deficiency (A1AD), heterozygous familial hypercholesterolemia (HeFH), and other indications. Visit https://epicrispr.com/ for more information or follow us on LinkedIn. Investor ContactBenson Cheng benson.cheng@epic-bio.com Media ContactLisa RaffenspergerTen Bridge Communicationslisa@tenbridgecommunications.com

- Presentations Will Feature Recent Clinical Data From DYNE-251 and DYNE-101 as Well as Preclinical Data in FSHD and Pompe Disease - WALTHAM, Mass., Oct. 09, 2024 (GLOBE NEWSWIRE) -- Dyne Therapeutics, Inc. (Nasdaq: DYN), a clinical-stage muscle disease company focused on advancing innovative life-transforming therapeutics for people living with genetically driven diseases, today announced that previously reported clinical and preclinical data across its pipeline will be featured in poster presentations at the 29th Annual Congress of the World Muscle Society, held virtually and in Prague, Czech Republic, October 8-12, 2024. The presentations highlight the promise of the FORCE™ platform to deliver targeted therapeutics to address neuromuscular diseases. “The full breadth and versatility of our FORCE platform is on display at this year’s World Muscle Society Congress, with presentations covering both of our co-lead clinical programs in DM1 and DMD, along with preclinical work in FSHD and Pompe disease,” said John Cox, president and chief executive officer of Dyne. “We’ve observed targeted delivery with the FORCE platform showing broad distribution to key tissues like skeletal, cardiac, smooth muscle and the CNS – which has the potential to transform the lives of individuals living with these diseases.” Poster Highlights The Phase 1/2 DELIVER trial evaluating DYNE-251 in males with Duchenne muscular dystrophy (DMD) mutations amenable to exon 51 skipping includes 6-month biomarker and functional data from patients enrolled in the 20 mg/kg (approximate PMO dose) cohort and 12-month functional data from the 10 mg/kg cohort. DYNE-251 demonstrated dose dependent exon skipping and dystrophin expression and improvement in multiple functional endpoints in both cohorts. Patients treated with 20 mg/kg of DYNE-251 Q4W had a mean absolute dystrophin expression of 3.7% of normal (unadjusted for muscle content) and when adjusting for muscle content, it reached 8.7%. Importantly, treatment with DYNE-251 resulted in meaningful improvements in Stride Velocity 95th Centile (SV95C), a digital objective outcome measure of ambulatory performance in a patient’s normal daily environment. The change from baseline in SV95C met the published minimal clinically important difference as defined by the European Medicines Agency (0.1 m/sec) at 6 months for both the 10 and 20 mg/kg cohorts (approximately 0.2 m/sec change from baseline for both cohorts).The Phase 1/2 ACHIEVE trial evaluating DYNE-101 in adult participants with myotonic dystrophy type 1 (DM1) includes 12-month data from the 1.8 mg/kg Q4W (approximate ASO dose) cohort, 6-month data from the 3.4 mg/kg Q4W cohort, and 3-month data from the 5.4 mg/kg Q8W cohort. DYNE-101 demonstrated robust muscle delivery and dose-dependent, consistent splicing correction while also showing improvement in myotonia, muscle strength, and timed function tests and in the Myotonic Dystrophy Type 1 Activity and Participation Scale (DM1-ACTIVc) and the Myotonic Dystrophy Health Index (MDHI) patient reported outcomes. Patients in the 5.4 mg/kg Q8W cohort had a 27% mean splicing correction from baseline across a broad, 22-gene panel at 3 months, with all participants demonstrating splicing correction.Both DYNE-251 and DYNE-101 have demonstrated favorable safety profiles. 1 2Preclinical data for DYNE-302 in facioscapulohumeral muscular dystrophy (FSHD), demonstrated robust and durable DUX4 suppression and functional benefit in an innovative hTfR1/iFLExD mouse model developed by Dyne. In hTfR1/iFLExD mice, a single intravenous dose of DYNE-302 resulted in dose-dependent and robust reduction of the DUX4 transcriptome (D4T) that lasted up to three months, with benefit on muscle structure and function.Preclinical data in a Pompe disease model demonstrated the potential of the FORCE platform to deliver enzyme replacement therapy to cardiac and skeletal muscle and the central nervous system (CNS), potentially expanding the modularity of the platform beyond oligonucleotides. Presentation Information Title: Initial Data from the DELIVER Trial of DYNE-251 in Males with DMD Mutations Amenable to Exon 51 SkippingDate/Time: October 9, 2024, 2:30 p.m. CEST/8:30 a.m. ETPresenter: Liesbeth De Waele, M.D., Ph.D., Pediatric Neurologist at University Hospital Leuven, Belgium Title: Initial Data from the ACHIEVE Trial of DYNE-101 in Adults with Myotonic Dystrophy Type 1 (DM1)Date/Time: October 9, 2024, 2:30 p.m. CEST/8:30 a.m. ETPresenter: Joost Kools, M.D., Neuromuscular Department at Radboud University Medical Center, Netherlands Title: The FORCE™ Platform Achieves Robust and Durable DUX4 Suppression and Improves Muscle Function in Facioscapulohumeral Muscular Dystrophy Mouse ModelDate/Time: October 9, 2024, 5:15 p.m. CEST/11:15 a.m. ETPresenter: Tyler Picariello, Ph.D., Director, Neuromuscular Research, Dyne Therapeutics Title: The FORCE™ Platform Enables Tfr1-mediated Delivery of Enzyme Replacement Therapy to Muscle and Central Nervous System, Resolving Pompe Pathology in MiceDate/Time: October 11, 2024, 3:45 p.m. CEST/ 9:45 a.m. ETPresenter: Tyler Picariello, Ph.D., Director, Neuromuscular Research, Dyne Therapeutics The presentations will be available in the Scientific Publications & Presentations section of Dyne’s website following the session. Additionally, a symposium titled “Potential of the FORCE™ Platform to Address Unmet Needs in Rare Neuromuscular Diseases” will be held on October 10 at 8:15 a.m. CEST/ 2:15 a.m. ET. About the FORCE™ Platform The proprietary FORCE™ platform drives Dyne’s efforts to develop targeted, modern oligonucleotide innovative therapeutics with the potential to be life-transforming for patients with serious muscle diseases. Dyne designed the FORCE platform using its deep knowledge of muscle biology and oligonucleotide therapeutics to overcome the current limitations in delivery to muscle tissue with the goal of stopping or reversing disease progression. The FORCE platform leverages the importance of transferrin receptor 1 (TfR1) in muscle biology as the foundation for its novel approach. TfR1, which is highly expressed on the surface of muscle cells, is required for iron transport into muscle cells. Dyne links therapeutic payloads to its TfR1-binding fragment antibody (Fab) to develop targeted therapeutics for muscle diseases. About Dyne Therapeutics Dyne Therapeutics is a clinical-stage muscle disease company focused on advancing innovative life-transforming therapeutics for people living with genetically driven diseases. With its proprietary FORCE™ platform, Dyne is developing modern oligonucleotide therapeutics that are designed to overcome limitations in delivery to muscle tissue. Dyne has a broad pipeline for serious muscle diseases, including clinical programs for myotonic dystrophy type 1 (DM1) and Duchenne muscular dystrophy (DMD) and preclinical programs for facioscapulohumeral muscular dystrophy (FSHD). For more information, please visit https://www.dyne-tx.com/, and follow us on X, LinkedIn and Facebook. Forward-Looking Statements This press release contains forward-looking statements that involve substantial risks and uncertainties. All statements, other than statements of historical facts, contained in this press release, including statements regarding Dyne’s strategy, future operations, prospects and plans, objectives of management, the potential of the FORCE platform, the potential of DYNE-101, DYNE-251 and DYNE-302, expectations regarding the timing and outcome of interactions with global regulatory authorities, and plans to provide future updates on pipeline programs, constitute forward-looking statements within the meaning of The Private Securities Litigation Reform Act of 1995. The words “anticipate,” “believe,” “continue,” “could,” “estimate,” “expect,” “intend,” “may,” “might,” “objective,” “ongoing,” “plan,” “predict,” “project,” “potential,” “should,” or “would,” or the negative of these terms, or other comparable terminology are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. Dyne may not actually achieve the plans, intentions or expectations disclosed in these forward-looking statements, and you should not place undue reliance on these forward-looking statements. Actual results or events could differ materially from the plans, intentions and expectations disclosed in these forward-looking statements as a result of various important factors, including: uncertainties inherent in the identification and development of product candidates, including the initiation and completion of preclinical studies and clinical trials; uncertainties as to the availability and timing of results from preclinical studies and clinical trials; the timing of and Dyne’s ability to enroll patients in clinical trials; whether results from preclinical studies and initial data from early clinical trials will be predictive of the final results of the clinical trials or future trials; uncertainties as to the FDA’s and other regulatory authorities’ interpretation of the data from Dyne's clinical trials and acceptance of Dyne's clinical programs and the regulatory approval process; whether Dyne’s cash resources will be sufficient to fund its foreseeable and unforeseeable operating expenses and capital expenditure requirements; as well as the risks and uncertainties identified in Dyne’s filings with the Securities and Exchange Commission (SEC), including the Company’s most recent Form 10-Q and in subsequent filings Dyne may make with the SEC. In addition, the forward-looking statements included in this press release represent Dyne’s views as of the date of this press release. Dyne anticipates that subsequent events and developments will cause its views to change. However, while Dyne may elect to update these forward-looking statements at some point in the future, it specifically disclaims any obligation to do so. These forward-looking statements should not be relied upon as representing Dyne’s views as of any date subsequent to the date of this press release. Safety data as of August 21, 2024Safety data as of August 20, 2024 Contacts: InvestorsAmy Reillyareilly@dyne-tx.com 857-341-1203 MediaStacy Nartkersnartker@dyne-tx.com 781-317-1938