Biotech company Avidity Biosciences anticipates filing for approval of their medication Del-zota for Duchenne Muscular Dystrophy by the end of the year.
Avidity Biosciences' Duchenne Muscular Dystrophy Treatment Advances
In a significant development for Duchenne muscular dystrophy (DMD) patients with mutations amenable to exon 44 skipping, Avidity Biosciences' investigational RNA therapy, del-zota, has received Breakthrough Therapy Designation from the U.S. FDA.
As of July 2025, the stock price for RNA, the company behind del-zota, stands at $33.69, representing a 0.46% increase. This designation is based on positive results from the completed Phase 1/2 EXPLORE44® trial, which demonstrated statistically significant increases in exon 44 skipping, substantial increases in dystrophin production, a significant and sustained reduction in creatine kinase levels to near normal, along with consistently favorable safety and tolerability profiles.
Del-zota works by delivering phosphorodiamidate morpholino oligomers (PMOs) conjugated to a monoclonal antibody targeting the transferrin receptor 1, which enables targeted exon skipping in skeletal and cardiac muscle. The therapy is currently under evaluation in an ongoing Phase 2 Open-Label Extension trial (EXPLORE44-OLE™) to further assess safety and efficacy.
Avidity Biosciences announced it remains on track to submit a Biologics License Application (BLA) by the end of 2025. The Breakthrough Therapy Designation, along with Rare Pediatric Disease, Orphan Drug, and Fast Track designations, supports an expedited regulatory pathway for del-zota.
The topline and functional data from the ongoing, fully enrolled phase II EXPLORE44-OLE trial are expected in the fourth quarter of 2025. In the last 1 year, RNA's stock has traded in a range of $21.51 to $56.00.
Duchenne muscular dystrophy is a rare genetic condition characterized by progressive muscle damage and weakness due to the loss of dystrophin protein, often beginning in early childhood. Del-zota is designed to deliver PMOs to skeletal muscle and heart tissue to specifically skip exon 44 of the dystrophin gene, enabling dystrophin production in people with DMD with mutations amenable to exon 44 skipping.
This positions del-zota as a promising RNA therapy close to potential regulatory approval for treating DMD patients amenable to exon 44 skipping.
| Aspect | Status/Update | |--------------------------|------------------------------------| | Clinical Development | Completed Phase 1/2; ongoing Phase 2 OLE | | Key Trial Outcomes | Exon 44 skipping ↑ ~40%, dystrophin ↑ up to 58% normal, creatine kinase ↓ >80% | | FDA Status | Breakthrough Therapy Designation granted July 2025 | | BLA Submission | Planned by end of 2025 |
Science and health-and-wellness intersect in the treatment of Duchenne muscular dystrophy, as medical-conditions like this rare genetic disorder require innovative therapies-and-treatments to combat its progression. The investigational RNA therapy, del-zota, from Avidity Biosciences, has shown potential in addressing DMD through exon 44 skipping, with positive results from Phase 1/2 trials and a forthcoming BLA submission by the end of 2025. The therapy, which utilizes phosphorodiamidate morpholino oligomers (PMOs) and a monoclonal antibody, aims to boost dystrophin production and reduce creatine kinase levels, thereby alleviating the symptoms of DMD.
