Dyne Therapeutics Presents Nonhuman Primate Proof of Concept Data on FORCE™ Therapeutic Platform at International Myotonic Dystrophy Consortium Meeting (IDMC-12)

• Data demonstrates clinically relevant levels of gene knockdown in
  nonhuman primates with a single dose of Dyne-102
• Company is developing pipeline of targeted therapies for patients
  with serious muscle diseases including DM1, DMD and FSHD

CAMBRIDGE, Mass.–(BUSINESS WIRE)–Dyne
Therapeutics, a biotechnology company pioneering targeted therapies
for patients with serious muscle diseases, today announced preclinical
data at the 12th edition of the International Myotonic Dystrophy
Consortium Meeting (IDMC-12) demonstrating the tissue specificity,
potency and tolerability of its FORCE™ therapeutic platform
in nonhuman primates. The company is advancing a treatment for myotonic
dystrophy type 1 (DM1), a rare, inherited muscle disorder caused by a
genetic mutation in the DMPK gene, in addition to programs for Duchenne
muscular dystrophy (DMD) and facioscapulohumeral muscular dystrophy
(FSHD).

Mo Qatanani, Ph.D., Dyne’s Vice President of Discovery and Translational
Research, presented data demonstrating clinically relevant levels of
gene knockdown in nonhuman primates. Key findings include:

• DMPK RNA knockdown in nonhuman primate skeletal, cardiac and smooth
  muscle tissues after a single dose of Dyne-102
• Comparable DMPK RNA knockdown at a 60 times lower total dose than a
  previous DM1 antisense oligonucleotide
• Demonstration of muscle-specific delivery vs. non-muscle tissues
• Favorable safety profile based on clinical blood chemistry analysis 2,
  7 and 14 days after dosing, with platelets, hemoglobin, reticulocytes,
  alanine aminotransferase (ALT), aspartate aminotransferase (AST) and
  blood urea nitrogen (BUN) remaining in the normal range throughout the
  study

“Existing oligo therapeutic programs for muscle diseases have
demonstrated the potential to knockdown target RNA in preclinical
studies. However, systemic exposure resulted in dose-limiting
toxicities, restricting their clinical development,” said Mo Qatanani.
“Our nonhuman primate data offers compelling evidence that the FORCE
therapeutic platform enables tissue-specific delivery that can
potentially lead to the development of highly potent and tolerable
medicines for a variety of muscle diseases.”

“These preclinical results showcase the enormous therapeutic potential
of Dyne’s FORCE therapeutic platform and represent a significant step
toward advancing targeted therapies for muscle diseases to the clinic,”
added Romesh Subramanian, Ph.D., President and CEO of Dyne. “We are
proud to lead the effort to bring life-changing oligo therapeutics to
patients with myotonic dystrophy and other serious muscle diseases
including DMD and FSHD.”

Details on Dyne’s presentation at IDMC-12 are as follows:

Title: Targeted Delivery of Oligonucleotide Therapeutics to
Muscle Reduces Toxic DMPK RNA
Time and Date: Thursday, June
13, 2019 at 3:30 PM CEST (9:30 AM ET)
Location: The Swedish
Exhibition and Congress Centre, Main session hall – G2+G3

About Dyne Therapeutics
Dyne Therapeutics is pioneering
therapies that target muscle tissue with unprecedented precision to
restore muscle health. The company’s FORCE™ platform delivers
oligonucleotides and other molecules to skeletal, cardiac and smooth
muscle to treat a range of serious muscle diseases. Dyne is advancing a
treatment for myotonic dystrophy type 1 (DM1) in addition to programs
for Duchenne muscular dystrophy (DMD) and facioscapulohumeral muscular
dystrophy (FSHD). Dyne launched in 2019 and is based in Cambridge, Mass.
For more information, please visit www.dyne-tx.com.

Contacts

Ten Bridge Communications
Max Stendahl, 508-277-8117
[email protected]