A baby born with an ultra‑rare and life‑threatening genetic disorder has taken his first steps after receiving a personalized CRISPR gene‑editing therapy at Children’s Hospital of Philadelphia.
A Rare Genetic Disorder
KJ Muldoon was diagnosed with CPS1 deficiency syndrome, a condition that occurs in only 1 in 1.3 million live births and carries a 50 % mortality rate. The disorder hampers the body’s ability to process certain proteins, making early intervention critical.
The Decision That Changed a Life
Within days of KJ’s birth, his parents, Nicole and Kyle, faced a daunting choice: pursue a liver transplant or try an experimental gene therapy that had never been used before. The decision would set the course for the child’s future.
The First‑Ever CRISPR Therapy
Earlier this year, KJ became the world’s first patient to receive a personalized CRISPR gene‑editing therapy designed specifically for CPS1 deficiency. The treatment was developed by a team led by Dr. Rebecca Ahrens‑Nicklas, a physician‑scientist in CHOP’s Metabolic Disease Program, and Dr. Kiran Musunuru, a cardiologist, geneticist, and professor at the University of Pennsylvania’s Perelman School of Medicine.
From Hospital to Home
For the first ten months of his life, KJ remained hospitalized while doctors monitored his progress closely. In June, after showing steady improvement, he was discharged and returned home with his family. Since then, he has reached milestones that once seemed unlikely.
Milestones and New Hope
KJ celebrated his first birthday in August and, most recently, took his very first steps. A spokesperson for CHOP shared in a news release, “He’s also getting ready to celebrate his first Christmas at home, something that had to happen in his hospital room a year ago.” These achievements offer new hope for the future of personalized gene therapy.
Broader Implications for Rare Diseases
According to CHOP, researchers are continuing to explore the causes and potential treatments for other difficult‑to‑treat metabolic disorders. KJ’s case is also prompting discussions on how to move forward with new models for approving personalized therapies for rare diseases.
Key Takeaways
- KJ Muldoon, born with CPS1 deficiency, received the world’s first personalized CRISPR therapy.
- The treatment was developed by Dr. Rebecca Ahrens‑Nicklas and Dr. Kiran Musunuru.
- After discharge in June, KJ celebrated his first birthday and first steps, marking significant progress.
KJ’s journey illustrates the power of cutting‑edge science to transform lives and highlights the need for new approval pathways for personalized treatments in rare diseases.
