Sanofi is pleased to announce that the US Food and Drug Administration (FDA) has granted Fast Track designation to SAR446268, Sanofi’s one-time AAV (adeno-associated virus) gene therapy aimed at treating non-congenital myotonic dystrophy type 1 (DM1).
Addressing a Critical Unmet Need
DM1 is a rare genetic disorder characterised by progressive muscle weakness, myotonia (difficulty relaxing muscles), and multi-systemic complications affecting the heart, respiratory system, and endocrine organs. There is currently no approved therapy for DM1 in any market.
How SAR446268 Works
SAR446268 is engineered to silence the DMPK gene transcript via an RNA interference (RNAi) mechanism, delivered through an AAV vector in a single administration. By lowering DMPK expression, the therapy aims to disrupt the downstream toxic RNA foci and restore more normal RNA splicing and muscle function.
Why the Fast Track Designation Matters
The Fast Track status is intended to facilitate development and expedite FDA review for therapies targeting serious or life-threatening conditions with unmet needs. This designation may enable more frequent interactions with the FDA and a potentially accelerated path to approval—all designed to benefit patients more rapidly.
Clinical Stage & Next Steps
SAR446268 is currently in a Phase 1-2 first-in-human trial (identifier: NCT06844214), assessing safety, tolerability, and early signals of efficacy. Patient enrolment is expected to begin in late 2025.
Quotes from Sanofi Leadership
“This Fast Track designation reaffirms the significance of SAR446268’s potential to transform care for patients living with DM1, said Sanofi.
