Karolinska Institutet readies first in utero stem cell trial

Karolinska Institutet is preparing to start the first-ever clinical trial in which stem cells will be injected into unborn babies. The research team hopes the administration of fetal stem cells to babies while still in the womb will prevent the development of the brittle-bone disease osteogenesis imperfecta.

Great Ormond Street Hospital's Lyn Chitty

Researchers at Karolinska Institutet have already given the therapy to two people--the oldest of whom is now 13 years old and doing better than expected--but the trial is the first time it has been tested in a more rigorous manner. When the trial gets underway in January 2016, research hospitals across Europe will start performing genetic tests to identify babies at risk of developing osteogenesis imperfecta, a disorder that can be fatal to newborns. People with the disorder who survive break bones easily throughout their life, have weak hearing and suffer from growth problems.

"This is a very serious disease. Our objective is to see if in utero stem cell therapy can ameliorate the condition and the number of fractures," Great Ormond Street Hospital's Lyn Chitty told BBC News. The stem cells, which are taken from terminated pregnancies, are intended to improve outcomes for people with the genetic disorder by compensating for their inability to form collagen. If the stem cells form collagen in the fetuses as hoped, the babies could go on to have stronger bones than would otherwise have been possible.

The trial plans to enrol 30 participants, half of whom will receive the treatment in the womb. The remaining participants will only start to receive stem cells after they are born. Participants in both arms of the study will then receive stem cells every 6 months for two years. The design of the trial, which lacks a placebo-controlled arm, has made some observers sceptical about its ability to prove whether the stem cells are effective, primarily because the severity of the symptoms of the disease vary from patient to patient.

King's College London's Dusko Ilic said: "People with the same type of osteogenesis imperfecta may present a different clinical picture, even within the same family. At the same time, cellular therapy is unlikely to work to the same extent in different individuals. How will we know whether a milder phenotype in a child that received the treatment is natural or is a result of the treatment?" The research team is confident in the trial, though, and has already started speculating about other possible target indications. Duchenne muscular dystrophy is among the disorders being considered.

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