To Evaluate the Safety of Long-term Use of HPN-100 in the Management of Urea Cycle Disorders (UCDs)

The duration of treatment in this study was open-ended. Participants were to return for clinic visits as prescribed by the investigator, and were to be seen at a minimum of every 6 months. At each clinic visit, participants were queried about any adverse events (AEs) or hyperammonemic crises (HACs) that occurred since the last visit. Physical and neurological examinations were performed, and blood samples were collected for the analysis of ammonia, amino acid panels, and routine clinical laboratory safety tests. Participants underwent neuropsychological testing at baseline, every 12 months thereafter, and at the final study visit. Study acquired from Horizon in 2024.