Two Philadelphia doctors who saved the life of a Clifton Heights baby boy with a groundbreaking treatment are among TIME’s 100 Most Influential People of 2026, writes Alexandra Simon and Stephanie Stahl for CBS News.
Dr. Kiran Musunuru of Penn and Dr. Rebecca Ahrens-Nicklas of CHOP were recognized for their CRISPR gene-editing therapy, which helped save the life of KJ Muldoon.
KJ has a rare urea cycle disorder, which makes ammonia build up in his body.
The ammonia can be toxic to the brain and cause permanent neurologic damage, said Dr. Ahrens-Nicklas
The doctors led a team from Penn and CHOP using CRISPR gene editing to edit out KJ’s defective DNA and replace it with an altered, repaired sequence.
KJ had spent 300 days in the hospital but was so improved from the treatment that he went home in June 2025.
“This achievement goes beyond one child. Musunuru and Ahrens-Nicklas brought together innovations from across biomedical science and proved that on-demand CRISPR therapies can be developed safely and quickly enough to help patients who don’t have years to wait,” Nobel Prize-winning biochemist Jennifer Doudna wrote for TIME.
Read about efforts underway now to expand access to personalized gene therapies at CBS News.
