Del-zota (delpacibart zotadirsen) for Duchenne muscular dystrophy (exon 44 skipping)
The FDA is expected to decide on Del-zota for Duchenne muscular dystrophy (exon 44 skipping) in an undisclosed window, under a BLA from Novartis.
What is being decided
Novartis has a BLA under FDA review for Del-zota (delpacibart zotadirsen) in Duchenne muscular dystrophy (exon 44 skipping). Antibody-linked exon 44 skipping therapy designed to carry the drug into skeletal and heart muscle, for people with Duchenne whose mutations are amenable to exon 44 skipping. The FDA accepted the application for priority review under the accelerated approval pathway, based on the Phase 1/2 EXPLORE44 trial and its open-label extension; a global Phase 3 trial now underway is the confirmatory study. Novartis disclosed the acceptance on September 8, 2026 but has not disclosed a target action date.
Who this decision matters to
Duchenne muscular dystrophy is an X-linked genetic disorder causing progressive muscle weakness and degeneration, beginning in early childhood. The defective dystrophin protein normally protects muscle fibers from damage. Without it, muscles deteriorate and are gradually replaced by fat and scar tissue. Multiple exon-skipping therapies (eteplirsen, golodirsen, viltolarsen, casimersen) are FDA-approved. Delandistrogene moxeparvovec (Elevidys), the first gene therapy for DMD, received accelerated FDA approval in June 2023. In June 2024 the FDA granted traditional approval for ambulatory patients (those who can walk) aged 4 and older and accelerated approval for non-ambulatory patients. After 2 deaths from acute liver failure in non-ambulatory patients, the FDA announced an investigation in June 2025, and in July 2025 it asked Sarepta to pause all shipments; on July 28, 2025 it recommended that treatment of ambulatory patients resume. In November 2025, the FDA added a boxed warning (its most serious warning) for acute serious liver injury and acute liver failure, including deaths, and limited the indication to ambulatory patients aged 4 and older, so Elevidys is no longer approved for non-ambulatory patients.
Prevalence: 1 in 3,500 to 5,000 male births. See our full Duchenne Muscular Dystrophy page for current treatments, recruiting trials, and community resources.
What each outcome would mean
An approval starts a second race rather than ending the first one: specialty pharmacy setup, insurance review, and patient assistance typically take weeks even when everything goes right. Our guide to the 90 days after a rare disease approval explains the timeline and the moves families can make on day 1.
A complete response letter would mean the FDA declined to approve in the application's current form. CRLs are often about manufacturing or data presentation rather than efficacy, and resubmission is common. Either way, this page updates with the outcome and what it means.
Where Duchenne Muscular Dystrophy treatment stands today
DMD research is remarkably active, with multiple exon-skipping therapies approved or in advanced trials, offering hope for slowing or stabilizing disease progression. Two newer oral medicines are FDA approved for DMD regardless of the specific mutation: vamorolone (Agamree), a once-daily corticosteroid liquid approved in October 2023 for patients 2 years and older, and givinostat (Duvyzat), a twice-daily histone deacetylase (HDAC) inhibitor liquid that targets inflammation and muscle loss, approved in March 2024 for patients 6 years and older. Gene therapy approaches are expanding, and newer antisense oligonucleotides are being tested for additional dystrophin mutations. The Muscular Dystrophy Association maintains a comprehensive trial database. These advances are most impactful when started early, so if you have a recently diagnosed child, discuss with your neurologist which newer therapies might be appropriate and monitor emerging trial opportunities. Genetic testing to identify your specific dystrophin mutation can help determine which targeted therapies you're eligible for.
Meanwhile, 81 Duchenne Muscular Dystrophy trials are recruiting
Whatever the FDA decides here, research on Duchenne Muscular Dystrophy does not stop. A few currently enrolling studies, US sites first:
Other drugs Trial Friend tracks for Duchenne Muscular Dystrophy
Get notified when new duchenne-muscular-dystrophy trials open or existing trials change status, add sites, or update eligibility.
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Frequently asked questions
When will the FDA decide on Del-zota?
Novartis has disclosed a decision window of later this cycle for Del-zota in Duchenne muscular dystrophy (exon 44 skipping), without an exact date.
What is Del-zota being reviewed for?
Novartis submitted a BLA for Del-zota in Duchenne muscular dystrophy (exon 44 skipping). Antibody-linked exon 44 skipping therapy designed to carry the drug into skeletal and heart muscle, for people with Duchenne whose mutations are amenable to exon 44 skipping. The FDA accepted the application for priority review under the accelerated approval pathway, based on the Phase 1/2 EXPLORE44 trial and its open-label extension; a global Phase 3 trial now underway is the confirmatory study. Novartis disclosed the acceptance on September 8, 2026 but has not disclosed a target action date.
What happens after the Del-zota decision?
If approved, availability is not immediate: specialty pharmacy setup, insurance review, and patient assistance typically take weeks even when everything goes right. If the FDA issues a complete response letter, the application was not approved in its current form; CRLs are often about manufacturing or data presentation rather than efficacy, and sponsors frequently resubmit. This page updates with the outcome either way.
Where this date comes from
The FDA does not publish PDUFA dates; companies disclose them. This one comes from Novartis SEC filing. Dates can move, and the FDA can act early or late. This page rechecks against our calendar, which is re-verified daily.