Baby with ornithine transcarbamylase (OTC) deficiency responds well to gene therapy trial

A little boy with a rare genetic disorder makes “incredible” progress after he became the first child to receive a new revolutionary gene therapy.

Tomas of fourteen months were diagnosed with a deficiency in transcarbamylase ornithin (OTC) ornithin at the age of a few weeks – becoming one of the 15 each year diagnosed with rare genetic disease.

An OTC deficiency is when ammonia, a waste generated when the body breaks down the proteins, accumulates in a person’s blood.

Ammonia is generally treated in the liver and removed by urine, but patients with disease have a genetic deficiency in the protein in the liver which is responsible for detoxifying ammonia, allowing ammonia to accumulate, which can be toxic.

It can cause potentially fatal complications, in particular brain lesions, coma or convulsions, if it is not treated.

Treatment may include the elimination of diet proteins and drugs known as “treasure therapy” – but in serious cases is not enough. Some patients, especially baby boys with state, sometimes require a liver transplant.

We thought that a transplant would be the only option for Tomas, until it is registered in the trial of revolutionary gene therapy at Large Ormond Street Hospital (Gosh) in London.

Symptoms of the disease usually start to show shortly after birth, especially extreme fatigue, the inability to eat and vomit.

Tomas’ parents noticed that something was wrong when he only had a week.

“Tomas became insensitive to the house and would not open his eyes, which was really scary

“We called an ambulance and we were taken to our local hospital. When we arrived, doctors could not determine what was wrong with Tomas.

“We spent the whole day there, from morning to evening, when they suspected an infection but were not some. Tomas would, and unfortunately wise us, could not help us. It was then that we were transferred by ambulance to Gosh.

“When we arrived in Gosh, in an hour or two, they told us that the Tomas ammonia level was too high.”

The doctors of the world-renowned children’s hospital diagnosed him with an over-the-counter deficiency and asked him if he wanted to be registered in the OTC-Hope test.

The test examines the gene therapy which is delivered via a infusion to reach the patient’s liver cells and was designed to restore the damaged OTC gene with a functional copy.

The researchers said that new therapy, called Ecur -506, uses a new way to insert a gene – the copy of the OTC operating gene is designed to be inserted very precisely to a location specified in one of the chromosomes.

We hope that the treatment will be comparable to the results observed in a liver transplant in over -the -counter patients – but using a punctual treatment instead.

Tomas received treatment last summer.

Transcarbamylase ornithin (OTC) Symptoms

Metabolic support UK

Mariana said: “Six months later and he no longer needs steroids and made good progress – he no longer needs a special diet and treasure drugs.

“We are extremely grateful for the help and support that we have received from Gosh’s doctors and nurses.

“We thought that a liver transplant would be the only option of Tomas and it would be difficult. We are so happy that he could have generated gene – it was incredible. We recently celebrated his first birthday.”

The main study investigator, Julien Baruteau, metabolic medicine consultant at Gosh and a clinician specialist in the University College London Great Ormond Street Institute of Child Health, “said:” We are delighted to see Tomas’ progress from gene therapy.

“He no longer needs the standard treatment of ammonia scavengers and eats protein levels adapted to age for a baby of his age.

“The standard of care for babies with a deficiency in neonatal OTC is based on liver transplantation in early childhood, a procedure presenting a significant risk of complications.

“This new approach to gene therapy could allow babies with the condition of avoiding this.

“I hope that Tomas will continue in this encouraging trajectory and that other babies who register for this study will have similar experiences.

“To our knowledge, it is the first time that a baby has been receiving gene therapy led by the liver. This new technology can announce new avenues to treat babies with serious hepatic genetic diseases. ”

Friday, Dr. Baruteau presents initial data at the annual meeting of clinical genetics in Los Angeles.