Exonics Therapeutics

About Exonics Therapeutics

Exonics Therapeutics was a biotechnology firm established to pioneer gene editing therapies for neuromuscular diseases, with an initial focus on Duchenne muscular dystrophy (DMD).

The company was co-founded in February 2017 by Dr. Eric N. Olson, a distinguished molecular biologist from the University of Texas Southwestern Medical Center, and the venture philanthropy arm of the patient advocacy group CureDuchenne. Dr. Olson, a leading expert in muscle biology, dedicated his career to understanding the molecular underpinnings of heart and muscle development. His extensive research into muscle gene regulation and the discovery of key genetic pathways naturally led to exploring the therapeutic potential of CRISPR gene editing for monogenetic muscle disorders. This culminated in the founding of Exonics to translate his lab's discoveries into clinical applications.

Exonics' primary technology was a gene editing approach called SingleCut CRISPR. This technique utilizes CRISPR/Cas9 technology delivered via an adeno-associated virus (AAV) to make a single cut in the DNA at specific mutation hotspots within the dystrophin gene. This process is designed to correct the reading frame of the gene, enabling the production of a functional, albeit shortened, dystrophin protein. The key benefit of this approach is its potential as a one-time treatment to permanently correct the underlying genetic defect for a large percentage of DMD patients, as many mutations are clustered in these hotspots. Preclinical studies in animal models, including mice and canines, demonstrated significant restoration of dystrophin protein in skeletal and heart muscle.

The company's business model was centered on advancing this proprietary gene editing platform through preclinical and clinical development to create transformative therapies. Its clients were, ultimately, patients suffering from devastating neuromuscular diseases with no available cures. Initial operations were fueled by a $5 million seed investment from CureDuchenne Ventures in February 2017, followed by a $40 million Series A financing round led by The Column Group in November 2017. In June 2019, just over two years after its inception, Exonics was acquired by Vertex Pharmaceuticals in a deal valued at up to approximately $1 billion, including a $245 million upfront payment and further milestone-based payments. The acquisition integrated Exonics' technology and scientific expertise into Vertex's growing genetic therapies portfolio, making it a wholly-owned subsidiary to accelerate the development of treatments for DMD and Myotonic Dystrophy Type 1 (DM1).