04/07/2026
This powerful story from the National Urea Cycle Disorders Foundation shares one family’s journey with arginase 1 deficiency—and the years of advocacy, research, and perseverance that helped turn hope into progress with the first FDA‑approved treatment for this rare disease.
The treatment is built on foundational research led by Dr. Brendan Lee and Dr. Lindsay Burrage, whose work helped pave the way for a therapy that can finally address the underlying cause of ARG1-D.
This milestone highlights the impact of rigorous, long‑term research combined with committed clinical and patient partnerships.
🎉 Hope realized.
When Tanja Brandt's daughter was diagnosed with arginase 1 deficiency (ARG1-D) at age 5, there were no approved treatments — only a difficult diet, daily formula, and a slow progression of symptoms Tanja and her mother Chris watched helplessly.
That changed on February 23, 2026, when the FDA approved pegzilarginase (Loargys®)—the first treatment to address the root cause of ARG1-D.
Getting here wasn't easy. The road included a clinical trial interrupted by Covid, a devastating loss of drug access, a patient petition, and years of fierce advocacy by families who refused to give up.
Read the full story of how one family—and an entire rare disease community—fought to make this moment happen. 👇
https://nucdf.org/news.html/article/2026/04/07/from-diagnosis-to-hope-an-arg1-d-family-s-fight-for-a-rare-disease-treatment
"This is not just a milestone. This is hope realized." — Chris Zahn, Arginase Deficiency Foundation