A cell therapy called deramiocel could slow muscle weakening in boys and young men with advanced Duchenne muscular dystrophy (DMD), and may also slow heart damage in those who already have heart muscle disease, a phase 3 clinical trial published in The Lancet has found. It is the first phase 3 trial of a cell therapy made from donor cells and administered through the bloodstream to treat a genetic disease, and the first such trial in boys and young men whose DMD is already advanced. The therapy is grown from heart cells that were donated for transplant but could not be used.
There is no cure for DMD, which is a serious genetic condition that causes the muscles, including the heart, to gradually weaken and waste away. It almost exclusively affects boys and young men, because the gene involved sits on the X chromosome. As the disease progresses, most patients lose the ability to walk and come to depend on their arms and hands for everyday tasks and independence.
The HOPE-3 trial involved 106 boys and young men aged 10 to 22 with advanced DMD, who were treated at 20 trial sites across the USA. They were randomly assigned to receive either deramiocel (54 people) or a placebo (52 people), given as a drip into the bloodstream every three months for a year at an outpatient clinic.
After one year, participants given deramiocel were losing the use of their arms more slowly than those given the placebo. Their overall arm movement declined about 54% more slowly than in the placebo group, and their elbow movement about 65% more slowly. Across all participants, the therapy made no clear difference to how well the heart pumped blood. Among the 64 participants who already had heart muscle disease and had suitable heart scans, heart function was better preserved with deramiocel than with placebo. In a smaller group of 22 participants whose scans could be compared before and after treatment, deramiocel was also linked to less spread of heart scarring, but further research is needed to confirm this finding.
The therapy was generally safe and no deaths were reported during the trial. Allergic-type reactions were more common with deramiocel (42%) than with placebo (15%). Almost all side effects were mild or moderate and cleared up within a day or two. The most common were headache, cough, fever, nausea, and a fast heartbeat.
The authors say deramiocel has the potential to help people with any type of DMD mutation, because it targets the swelling and scarring the disease causes in the muscles rather than the gene mutation itself. Heart problems are a major cause of death in DMD, and the authors call for further studies to find out whether the heart benefits seen in this trial help people live longer.
The US Food and Drug Administration (FDA) is scheduled to discuss deramiocel at an advisory committee meeting on 29th July 2026, with a decision on whether to approve the therapy expected by 22nd August 2026: https://www.federalregister.gov/documents/2026/06/29/2026-13096/cellular-tissue-and-gene-therapies-advisory-committee-notice-of-meeting-establishment-of-a-public
The Lancet
Deramiocel heart-derived cellular therapy in advanced Duchenne muscular dystrophy (HOPE-3): a phase 3, randomised, double-blind, placebo-controlled trial
29-Jul-2026
CMM served as site principal investigator for Capricor Therapeutics; received reimbursement for travel for study-related meetings and their institutions received payment for the conduct of the study; received grants from and served as site principal investigator for Avidity Biosciences, Edgewise Therapeutics, Insmed, and Italfarmaco, NS Pharma, PTC Therapeutics, Roche, Santhera Pharmaceuticals, Sarepta Therapeutics, and Solid Biosciences; has received grants from California Institute for Regenerative Medicine, Muscular Dystrophy Association, Parent Project Muscular Dystrophy, Shriners Hospitals for Children, Department of Defense, National Institute of Disability Independent Living and Rehabilitation Research, and the US National Institutes of Health (RO1HD35714, 2P01HD033988–06A1, R01NS043264, R01AR061875, R01AR062380, U01NS061799–01A2, P50AR060836, U10NS077422, U01AR065113–01, U24NS107209–01, U24 NS107209, R01DK129793–01, and R01DK125794–01A1); has received consultancy fees from Catalyst Pharmaceuticals, Capricor Therapeutics, Catabasis, Dyne, Edgewise Therapeutics, Italfarmaco, NS Pharma, PTC Therapeutics, Roche, Santhera Pharmaceuticals, Sarepta Therapeutics, and Solid Biosciences; and served on advisory boards for Avidity Biosciences, Catalyst Pharmaceuticals, Edgewise Therapeutics, Entrada Therapeutics, Santhera Pharmaceuticals, Sarepta Therapeutics, Solid Biosciences, and Roche. ASV served as site principal investigator for Capricor Therapeutics; received reimbursement for travel for studyrelated meetings and their institutions received payment for the conduct of the study; received payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing, or educational events from Biogen, Argenx, and Blue Oak Nutraceuticals; received payment for expert testimony as medical legal consultant; received support for attending meetings or travel from Argenx and Muscular Dystrophy Association; holds a leadership or fiduciary role for Sjogren’s Foundation; and owns stock or stock options from Blue Oak Nutraceuticals. LR-P served as site principal investigator for Capricor Therapeutics; received reimbursement for travel for study-related meetings and their institutions received payment for the conduct of the study; served as site principal investigator for Sarepta Therapeutics, Scholar Rock, Genentech, Biohaven, Novartis, PTC Therapeutics, and NS Pharma; received consulting fees and served on advisory boards for Sarepta Therapeutics, Scholar Rock, IFT Therapeutics, Catalyst Pharmaceuticals, Mando Therapeutics, Novartis, Dyne Therapeutics, and Solid Biosciences; and received payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing, or educational events from Scholar Rock. RJB served as site principal investigator for Capricor Therapeutics; received reimbursement for travel for studyrelated meetings and their institutions received payment for the conduct of the study; served as site principal investigator for Ionis Pharmaceuticals; and received consulting fees and served on the Scientific Advisory Board for Sarepta Therapeutics, Biogen, Novartis, Precision BioSciences, Solid Biosciences, Scholar Rock, and BridgeBio Pharma. KMo served as site principal investigator for Capricor Therapeutics; received reimbursement for travel for study-related meetings and their institutions received payment for the conduct of the Articles 12 www.thelancet.com Published online July 29, 2026 https://doi.org/10.1016/S0140-6736(26)01385-1 study; received support for attending meetings or travel from Capricor Therapeutics; participated on a data safety monitoring board or advisory board for Solid Biosciences, Catalyst Pharmaceuticals, and Sarepta Therapeutics; and holds a leadership or fiduciary role at American Association of Neuromuscular & Electrodiagnostic Medicine (AANEM). AV served as site principal investigator for Capricor Therapeutics; received reimbursement for travel for study-related meetings and their institutions received payment for the conduct of the study; and received consulting fees from Capricor Therapeutics, Biogen, Novartis, PTC Therapeutics, Sarepta Therapeutics, Scholar Rock, Pfizer, Catalyst Pharmaceuticals, Lupin, Entrada Therapeutics, Avidity Biosciences, Solid Biosciences, REGENXBIO, Insmed, Keros Therapeutics, Precision BioSciences, Gruenenthal, Mesoblast, and Italfarmaco. CGL served as site principal investigator for Capricor Therapeutics; received reimbursement for travel for study-related meetings and their institutions received payment for the conduct of the study; served as site principal investigator for Sarepta Therapeutics, Dyne Therapeutics, Biohaven, Avidity Biosciences, and Novartis; received consulting fees from Sarepta Therapeutics, Genentech, and Italfarmaco; and received payment for expert testimony from Stanford University. SA served as site principal investigator for Capricor Therapeutics; received reimbursement for travel for study-related meetings and their institutions received payment for the conduct of the study; served as site principal investigator for Sarepta Therapeutics, Dyne Therapeutics, and Satellos Bioscience; received consulting fees from ITF Therapeutics; received payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing, or educational events from Dyne Therapeutics; received support for attending meetings or travel from Dyne Therapeutics; and holds a leadership or fiduciary role as a Board of Director for American Board of Physical Medicine and Rehabilitation as well as a Board Director for Parent Project Muscular Dystrophy. STI served as site principal investigator for Capricor Therapeutics; received reimbursement for travel for study-related meetings and their institutions received payment for the conduct of the study; and received support for attending meetings or travel from Capricor Therapeutics. KDM served as site principal investigator for Capricor Therapeutics; received reimbursement for travel for study-related meetings and their institutions received payment for the conduct of the study; served as site principal investigator for PTC Therapeutics, Sarepta Therapeutics, Edgewise Therapeutics, and Italfarmaco; received support for attending meetings or travel from Sarepta Therapeutics; participated on a data safety monitoring board or advisory board for Dyne Therapeutics, Edgewise Therapeutics, and Avidity Biosciences; and holds a leadership or fiduciary role on the Research Advisory Committee for Muscular Dystrophy Association. ECS served as site principal investigator for Capricor Therapeutics; received reimbursement for travel for studyrelated meetings and their institutions received payment for the conduct of the study; received payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing, or educational events from Avidity Biosciences, Catalyst Pharmaceuticals, Precision BioSciences, Boehringer Ingelheim, Quince Therapeutics, Entrada, and Italfarmaco; and participated on a data safety monitoring board or advisory board for Solid Biosciences and Edgewise Therapeutics. SJP served as site principal investigator for Capricor Therapeutics; received reimbursement for travel for study-related meetings and their institutions received payment for the conduct of the study; served as site principal investigator for CSL Behring, Scholar Rock, Pfizer, Sarepta Therapeutics, Satellos Bioscience, Catalyst Pharmaceuticals, PTC Therapeutics, Biogen, Avexis, Solid Biosciences, and FibroGen; received clinical grant support from Muscular Dystrophy Association, Parent Project Muscular Dystrophy, and Cure SMA; received payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing, or educational events from the American Academy of Neurology; received support for attending meetings or travel from Capricor Therapeutics, Muscular Dystrophy Association, Parent Project Muscular Dystrophy, Cure SMA, and the American Board of Psychiatry and Neurology; participated on a data safety monitoring board or advisory board for Solid Biosciences, Catalyst Pharmaceuticals, Sarepta Therapeutics, Entrada Therapeutics, Novartis, and Dyne Therapeutics; and holds a leadership or fiduciary role as a Committee Member on the American Board of Psychiatry and Neurology. NEB, SMB, JAE, KG, PSG, HCP, and CT served as site principal investigators for Capricor Therapeutics; and received reimbursement for travel for study-related meetings and their institutions received payment for the conduct of the study. RJS served as site principal investigator for Capricor Therapeutics; received reimbursement for travel for study-related meetings and their institutions received payment for the conduct of the study; received research funds from Novartis, Sarepta Therapeutics, Genentech, Argenx, Biohaven, Catalyst Pharmaceuticals and Biogen; and received consulting fees and served on Medical Advisory Board for RegenXBio and Scholar Rock. MT was employed on this study by Medpace and owns equity in Capricor Therapeutics. EMa is an inventor of several patents licensed by Capricor Therapeutics, and owns founder’s equity in Capricor Therapeutics. JHS received grants or contracts from Ametris (R61HL180327/R33, R01HL167969, R01HL164995, R01FD006649, and R01FD006371); received consulting fees from Capricor Therapeutics, Boehringer Ingelheim, Catalyst Pharmaceuticals, Dyne Therapeutics, Keros Therapeutics, Medpace, NS Pharma, Sarepta Therapeutics, Secretome Therapeutics, Sardocor, and Wave Life Sciences; received support for attending meetings or travel from Capricor Therapeutics; participated on a data safety monitoring board or advisory board for Sardocor, Solid Biosciences, ITF Therapeutics, Sarepta Therapeutics, and Boehringer Ingelheim; holds a leadership or fiduciary role as the Chair and Chair Ex Officio of Pediatric and Congenital Heart Disease Section of the Society for Cardiovascular Magnetic Resonance (SCMR PCHD), Steering Committee and Abstract Chair of SCMR Scientific Sessions Planning Committee; and owns stock or stock options from Secretome Therapeutics. CV received payments made to Cincinnati Children’s Hospital Medical Center for cardiac natural history in DMD; received consulting fees either directly or to their employer as well as reimbursement for travel from Capricor Therapeutics; received payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing, or educational events from Capricor Therapeutics; and received support for attending meetings or travel from Capricor Therapeutics. KNH received consulting fees as a masked second reader for CMR analysis from Capricor Therapeutics. JS received consulting fees either directly or to their employer as well as reimbursement for travel from Capricor Therapeutics. EMe received grants or contracts from Sarepta Therapeutics; received consulting fees from PTC Therapeutics, Sarepta Therapeutics, Edgewise Therapeutics, Santhera, Roche, Dyne Therapeutics, Solid Biosciences, Avidity Biosciences, Entrada Therapeutics, and NS Pharma; received payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing, or educational events from Sarepta Therapeutics, Santhera, Roche, and Dyne Therapeutics; participated on a data safety monitoring board or advisory board for Sarepta Therapeutics, Santhera, Roche, PTC Therapeutics, Dyne Therapeutics, Solid Biosciences, Avidity Biosciences, Entrada, Edgewise Therapeutics, and NS Pharma. EKH received payment through UC Davis for study site clinical trial operations; received grants or contracts from Sarepta Therapeutics, NS Pharma, Insmed, Santhera, Solid Biosciences, and Parent Project Muscular Dystrophy; received payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing, or educational events from Sarepta Therapeutics and Santhera; received support for attending meetings or travel from Parent Project Muscular Dystrophy; and holds a leadership or fiduciary role on the Scientific Advisory Board for Parent Project Muscular Dystrophy, the Executive Committee for Cooperative International Neuromuscular Research Group, and the Clinical Certification Committee for World Duchenne Organization. KMa, NH, MB, KCB, KAE, MSA, and LM are full time employees of and hold equity in Capricor Therapeutics.