- Avidity Biosciences is on track to file its first Biologics License Application (BLA) for **Dalzosia** (for boys and young men amenable to exon 44 skipping) by the end of **2025** for accelerated approval, with clinical updates expected in the next couple of weeks.  **[1599901_tx_380786_0]** **[1599901_tx_380786_2]** **[1599901_tx_380786_4]**  The company estimates approximately **900 boys and young men** in the U.S. are amenable to Exon 44 skipping.  **[1599901_tx_380786_3]** 
- Enrollment for the HARBOR study, a global Phase 3 pivotal study for **Daldistarone** (for myotonic dystrophy), was completed in **July**.  **[1599901_tx_380786_0]**  Data readout is guided for **Q2 2026**, with two-year follow-up data from the Mirena OLE study expected in **Q4 2025**.  **[1599901_tx_380786_0]** **[1599901_tx_380786_4]**  Myotonic dystrophy is estimated to affect **40,000 patients** in the U.S., with **10,000** already identified and genetically confirmed.  **[1599901_tx_380786_7]** 
- Enrollment for the FORTITUDE biomarker study for **Delbrax** (for FSHD) was completed in **March**.  **[1599901_tx_380786_0]**  Data readout is also guided for **Q2 2026**, and the company has reached alignment with the FDA on cDUX as the primary endpoint for accelerated approval.  **[1599901_tx_380786_0]** **[1599901_tx_380786_8]**  The opportunity size for FSHD is considered similar to, if not larger than, myotonic dystrophy.  **[1599901_tx_380786_8]** 
- Avidity Biosciences plans to globally commercialize its drugs itself, leveraging synergies across the programs as they all target muscle diseases and use the same antibody oligonucleotide conjugates (AOCs) platform.  **[1599901_tx_380786_0]** **[1599901_tx_380786_1]**

Avidity Biosciences (RNA)