A clinical trial to investigate whether a gene therapy treatment is safe and effective for a rare condition called ornithine transcarbamylase (OTC) deficiency has started in Newcastle.
The trial, called OTC-HOPE, is led by Dr Mark Anderson, consultant paediatrician at the Great North Children’s Hospital, and the trust’s paediatric research team.
OTC deficiency is a rare genetic condition that allows ammonia, a harmful waste, to build up in the blood. This happens because the OTC enzyme, which helps break down ammonia, is missing.
OTC deficiency can present at any age. The most severe form occurs in the first few days of life, usually following a protein feeding (e.g., milk, formula). This neonatal onset form of OTC deficiency usually affects newborn boys; it is very rare in newborn girls.

Early symptoms include vomiting, refusal to eat, tiredness, and irritability. If symptoms aren’t addressed, neonatal onset OTC deficiency can progress rapidly with other life-threatening complications.
Currently, a liver transplant is the only known curative treatment option for OTC deficiency; however, a liver transplant is not always possible, and not all children will qualify for one.
Other treatments, such as protein-restricted diet, help to lower ammonia levels, but don’t address the underlying genetic cause of the disease. They also don’t eliminate the risk of a life-threatening high ammonia crises.
The OTC-HOPE study aims to find out if the trial drug – ECUR 506 – is safe, as well as assess how effective it Is in treating neonatal onset OTC deficiency.
It is hoped that the information from this study may help improve the future treatment of people with the same condition.
You can find out more about OTC by watching this video. You can also watch a video explaining the trial.
Eligibility criteria and further info
Your baby may be eligible to participate in the OTC-HOPE study if he meets the following criteria (among others):
- Your baby is a boy between 24 hours and seven months of age at screening.
- Genetic testing has confirmed that your baby boy has OTC deficiency.
- Your baby boy has experienced severe OTC symptoms within the first week of life.
Additional eligibility criteria will be discussed with you during the screening process. Your study doctor and the study team will carefully assess your baby’s eligibility and provide further guidance on whether participation in the OTC-HOPE study is an option for your baby
To find out more about the trial, please contact [email protected] or call the lead research nurse on 0191 282 0609.