Keros Therapeutics, Inc.

Aug. 20, 2025 -- Keros Therapeutics, Inc. (“Keros”) (Nasdaq: KROS), a clinical-stage biopharmaceutical company focused on developing and commercializing novel therapeutics to treat a wide range of patients with disorders that are linked to dysfunctional signaling of the transforming growth factor-beta (“TGF-ß”) family of proteins, today announced the U.S. Food and Drug Administration (“FDA”) granted Orphan Drug designation for KER-065 for the treatment of Duchenne muscular dystrophy (“DMD”). “Receiving Orphan Drug designation for KER-065 highlights the significant unmet medical need for patients with DMD,” said Jasbir S. Seehra, President and Chief Executive Officer. “This designation serves as a significant milestone for Keros as we advance KER-065 into a Phase 2 clinical trial in patients with DMD.” The FDA grants Orphan Drug designation to investigational therapies addressing rare medical diseases or conditions that affect fewer than 200,000 people in the United States. This designation provides certain potential benefits, including tax credits for qualified clinical testing, waiver or partial payment of FDA application fees and seven years of market exclusivity, if approved. KER-065 is a novel ligand trap comprised of a modified ligand-binding domain derived from activin receptor type IIA and activin receptor type IIB that is fused to the portion of the human antibody known as the Fc domain. KER-065 is designed to act as a ligand trap and inhibit the biological effects of myostatin and activin A, two ligands that signal through activin receptors, to increase skeletal muscle regeneration, increase muscle size and strength, reduce body fat, reduce fibrosis of the skeletal muscle and increase bone strength. We are developing KER-065 for the treatment of neuromuscular diseases, with an initial focus on DMD. DMD is the most common form of muscular dystrophy and results in muscle degeneration and premature death. DMD results from the lack of functional dystrophin protein that helps promote myofiber stability, caused by a gene mutation. The lack of dystrophin, an important structural component of muscle cells, causes muscle cells to have increased susceptibility to damage and to progressively die. Additionally, the absence of dystrophin in muscle cells leads to significant cell damage and ultimately causes muscle cell death and the replacement of muscle with fibrotic and fatty tissue. The replacement of muscle fibers with fatty and fibrotic tissue leads to progressive loss of muscle strength and function leading to immobility and respiratory and cardiac complications. In DMD patients, heart muscle cells progressively die and are replaced with scar tissue. This cardiomyopathy eventually leads to heart failure, which is currently the leading cause of death among those with DMD. The National Organization for Rare Disorders estimates that approximately one in every 3,500 male births is affected by DMD worldwide. Keros is a clinical-stage biopharmaceutical company focused on developing and commercializing novel therapeutics to treat a wide range of patients with disorders that are linked to dysfunctional signaling of the TGF-ß family of proteins. Keros is a leader in understanding the role of the TGF-ß family of proteins, which are master regulators of the growth, repair and maintenance of a number of tissues, including blood, bone, skeletal muscle, adipose and heart tissue. By leveraging this understanding, Keros has discovered and is developing protein therapeutics that have the potential to provide meaningful and potentially disease-modifying benefit to patients. Keros’ lead product candidate, KER-065, is being developed for the treatment of neuromuscular diseases, with an initial focus on DMD. Keros’ most advanced product candidate, elritercept, is being developed for the treatment of cytopenias, including anemia and thrombocytopenia, in patients with myelodysplastic syndrome and in patients with myelofibrosis. The content above comes from the network. if any infringement, please contact us to modify.

AUSTIN, Texas, Aug. 21, 2025 /PRNewswire/ -- ADAR1 Capital Management, LLC (together with its affiliates, "ADAR1" or "we"), the largest stockholder of Keros Therapeutics (Nasdaq: KROS) ("Keros" or the "Company") with approximately 13.3% of the Company's outstanding shares, today released an open letter to Keros' Board of Directors (the "Board") expressing its disappointment with the Board's refusal to engage with ADAR1 on the Company's strategy, capital allocation priorities and Board refreshment. The full text of the letter is below. Dear Members of the Board: In July, we wrote to the Board privately to propose an in-person meeting to discuss our ideas to maximize stockholder value. We had hoped that the broad stockholder dissatisfaction evident in the results of the 2025 Annual Meeting would prompt the Board to adopt a more constructive and conciliatory approach to its engagement with investors. Unfortunately, that hope was misplaced. Rather than welcoming the opportunity to engage with the Company's largest stockholder, Keros' management team and Board have repeatedly declined to interact with us directly and instead referred us to the Company's financial advisor. As we have conveyed to you (and now to your financial advisor), we believe Keros is worth significantly more than the price at which its stock trades. Its valuation is supported, in our view, by the Company's large cash balance and the net present value of the Takeda partnership for elritercept, which we believe the Company should distribute to stockholders via CVR. Given the large and persistent undervaluation of the Company's stock, we would like to work collaboratively with the Board to unlock this value for all stockholders. In furtherance of that goal, we reiterate our request to meet with the independent directors as soon as practicable. We are available to meet at the Company's headquarters in Lexington or any other location that is convenient for you. Additionally, we are concerned by the lack of follow-through on the Company's June 9 announcement regarding the planned return of $375 million in excess capital. Shareholders have now waited for more than two months without any update on the timing or process for the return of capital. We urge the Company to promptly communicate a clear and detailed plan to return capital, specifically through the declaration of a special dividend. Our strong preference is to work together with the Board to help reorient the Company's strategic direction into one that benefits all shareholders. However, should the Board continue to refuse our invitations to engage, we will seek to elect new directors at the next Annual Meeting – directors who will embrace their role as fiduciaries and are willing to at least hear the perspectives of stockholders. In the meantime, we caution the Board against making any changes to its composition or to the Company's strategy without first seeking input from its major stockholders, including ADAR1. Keros has an opportunity to build significant long-term value for its investors, but doing so requires a Board that is willing to listen to and work constructively with its stockholders. We urge you to take this opportunity to engage with us in good faith. Sincerely, Daniel Schneeberger ADAR1 Capital Management About ADAR1 Capital Management ADAR1 Capital Management is an SEC-registered investment manager based in Austin, Texas, focused on public and private equity investments in the life sciences and biotechnology sectors. The firm was founded in October 2018 by Dr. Daniel Schneeberger, who brings over 20 years of experience spanning scientific research, healthcare consulting, institutional investing, and executive leadership in the healthcare industry. He is supported by a team of experienced professionals with deep medical and scientific expertise and a strong track record of biopharmaceutical investing. Contact: [email protected] 512-254-3790 SOURCE ADAR1 Capital Management, LLC WANT YOUR COMPANY'S NEWS FEATURED ON PRNEWSWIRE.COM? 440k+ Newsrooms & Influencers 9k+ Digital Media Outlets 270k+ Journalists Opted In GET STARTED

The therapy focuses on boosting skeletal muscle regeneration, increasing muscle mass and strength. Credit: Korawat photo shoot/Shutterstock.com. Keros Therapeutics has received orphan drug designation from the US Food and Drug Administration (FDA) for its investigational therapy KER-065 to treat Duchenne muscular dystrophy (DMD). KER-065 is a new ligand trap that combines a modified ligand-binding domain from activin receptors IIA and IIB with the Fc domain of a human antibody. Its mechanism is designed to inhibit the actions of myostatin and activin A ligands, which are involved in muscle signalling. The therapy aims to enhance skeletal muscle regeneration, increase muscle mass and strength, reduce skeletal muscle fibrosis, decrease body fat and improve bone strength. The initial focus of KER-065’s development is on treating neuromuscular diseases, particularly DMD. Keros president and CEO Jasbir Seehra stated: “Receiving orphan drug designation for KER-065 highlights the significant unmet medical need for patients with DMD. GlobalData Strategic Intelligence US Tariffs are shifting - will you react or anticipate? Don’t let policy changes catch you off guard. Stay proactive with real-time data and expert analysis. By GlobalData Learn more about Strategic Intelligence “This designation serves as a significant milestone for Keros as we advance KER-065 into a Phase II clinical trial in patients with DMD.” DMD arises from mutations in the gene responsible for producing dystrophin, a protein essential for myofibre stability. According to the US National Organization for Rare Disorders, DMD affects approximately one in every 3,500 male births globally. Keros is engaged in the development and marketing of new therapies for patients with disorders associated with dysfunctional signalling of the TGF-ß protein family. In April 2025, Keros’ board of directors approved a “poison pill defence” due to rising investor interest in “influencing the company’s control.” This decision follows expressions of interest from certain investors – including one individual with an 11.2% stake in Keros’s outstanding common stock – wishing to impact the company’s strategic decisions. Pharmaceutical Technology Excellence Awards - The Benefits of Entering Gain the recognition you deserve! The Pharmaceutical Technology Excellence Awards celebrate innovation, leadership, and impact. By entering, you showcase your achievements, elevate your industry profile, and position yourself among top leaders driving pharmaceutical advancements. Don’t miss your chance to stand out—submit your entry today! Nominate Now