FDA Awards Rare Pediatric Drug Designation to Stem Cell Product Candidate for Fatal Danon Disease

ISX9-CPC, a stem cell therapeutic candidate designed by ISP HEART, received a rare pediatric drug designation (RPDD) to treat cardiomyopathy associated with rare and fatal Danon disease, according to an ISP HEART press release. The therapeutic candidate may be able to generate new cardiac tissue to create a functional human heart muscle.¹

“While the rare disease community is largely focused on gene therapy approaches, gene therapy, unfortunately, cannot create new heart muscle nor can it create any new skeletal muscle or deliver full length dystrophin,” said Rauf Ashraf, chief executive officer of IPS HEART, in the press release. “[But] large pharmaceutical companies are starting to show clinical success with IPS stem cell therapy.”

ISX9-CPC, the first patented drug candidate created by the company, uses small molecule isoxazole 9 (ISX-9) to differentiate induced pluripotent stem cells (iPSCs) into cells that can create a functional heart muscle. The new heart muscle can also be used to treat heart failure and Duchenne muscular dystrophy, another type of skeletal and cardiac myopathy.

ISX9-CPC was previously awarded a second RPDD to treat Duchenne muscular dystrophy. This is an X-link dominant genetic condition that affects more males. It is characterized by atrophy that worsens over time. Eventually, skeletal and heart muscles become weak and ineffective. Because of the latter, the heart cannot effectively pump blood and enlarges, often causing death in the patient’s third decade of life.^2,3

Like Duchenne muscular dystrophy, Danon disease is the result of an X-link dominant gene mutation. Whereas it affects more males at an earlier age, females can develop Danon disease as well, although cases are usually milder and the disease develops in adulthood. Danon causes cardiopathy, or diseased heart muscle, weak body muscles (skeletal myopathy), and intellectual disability. Heart transplant is usually required by the second or third decade of life, otherwise the patient will die.¹

ISP HEART recently received an RPDD for a second drug candidate, GIVI-MPC—a stem cell therapy that uses the small molecule Givinostat to transform iPSCs into skeletal muscle tissue— for the treatment of Duchenne muscular dystrophy. GIVI-MPC is also capable of creating full-length human dystrophin, a type of protein that helps to stabilize the muscle fibers in the skeletal and cardiac muscles. GIVI-MPC was granted Orphan Drug Designation by the FDA to treat Duchenne muscular dystrophy.^1,3

“We are hopeful similar advances will be seen in devastating rare diseases,” Ashraf said.¹

References

1. IPS HEART. IPS HEART Receives U.S. FDA Rare Pediatric Drug Designation for ISX9-CPC Stem Cell Therapy for Treatment of Cardiomyopathy Associated with Danon disease. News Release. July 6, 2023. Accessed on July 7, 2023. https://www.businesswire.com/news/home/20230705216976/en
2. National Organization for Rare Disorders. Danon Disease. Reference. Updated February 9, 2023. Accessed on July 7, 2023. https://rarediseases.org/rare-diseases/danon-disease/
3. Medline. Duchenne and Becker muscular dystrophy. Reference. Accessed July 7, 2023. https://medlineplus.gov/genetics/condition/duchenne-and-becker-muscular-dystrophy/#:~:text=This%20protein%20is%20located%20primarily,functional%20dystrophin%20from%20being%20produced.