(Z)-Endoxifen Achieves Major FDA Regulatory Milestone In Duchenne Muscular Dystrophy Treatment

Atossa Therapeutics, Inc. (ATOS) has received significant regulatory recognition for its investigational therapy. The U.S. Food and Drug Administration’s Office of Orphan Products Development has now granted (Z)-endoxifen a special designation status for treating Duchenne muscular dystrophy (DMD), a rare genetic disorder. This regulatory milestone builds on the FDA’s previous decision to award the same candidate therapy Rare Pediatric Disease status, highlighting strong momentum in the clinical development pathway.

The market responded positively to this development. During Friday’s standard session, ATOS shares climbed to $0.6150, representing a 6.02% increase. Trading activity continued into after-hours markets, where the stock demonstrated additional strength, advancing to $0.6948—a further 12.98% gain through 7:59 PM EST.

What This Designation Means

The special designation status carries tangible benefits for drug developers targeting rare conditions. It typically accelerates the regulatory review timeline and provides tax incentives, among other support mechanisms designed to encourage innovation in underserved patient populations. For Atossa, securing this status reinforces the therapeutic potential of (Z)-endoxifen in addressing the significant medical gap that exists for DMD patients.

The combination of this newly awarded designation alongside the earlier Rare Pediatric Disease recognition signals multiple regulatory validation points, suggesting confidence in the clinical direction and unmet medical need this therapy is designed to address.