At Tübingen Department of Ophthalmology in Germany, the first gene therapy trial for Choroideremia patients began on January 13th. This milestone was preceded by many years of preparatory work in Tübingen – sponsored by the nonprofit Tistou and Charlotte Kerstan Foundation. In this case, the team was able to move forward based on results from Oxford, where Professor Robert MacLaren developed this new treatment and tested for the first time on patients in the United Kingdom. At this time, more than 20 patients have been treated at several centers in the context of clinical studies around the world. In addition to the original center at Oxford Eye Hospital, trials are currently underway in Edmonton (Canada), Miami (USA). Tübingen is the latest center to begin trials for Choroideremia patients.
The aim of gene therapy is a therapeutic gene sequence to replace a mutated gene, which is responsible for a disease like Choroideremia. By introducing the therapeutic gene, the disease process can be stopped. This works not only in the laboratory – even in children (in the case of another severe retinal disease, Leber’s Congenital Amaurosis) it works so well that an approval for general treatment is likely.
In the case of Choroideremia, it also seems to work well. Initial results have confirmed the safety of the treatment and shown a positive effect For example, in the microperimetry (a kind of visual field examination), the higher the relative dose, the greater was the increase in sensitivity of the treated retina (MacLaren et al, Lancet, January 2014). However, the goal of treatment can also be seen in the natural disease progression – the steady deterioration of visual function stops, with no further progression towards blindness. Many adult patients with Choroideremia know their sight is getting worse and there is currently no other treatment option, the interest in these studies is very high.
We thank the Tübingen University Eye Clinic team (Director: Prof. Bartz-Schmidt) and the Research Institute of Ophthalmology team (Director: Prof. Ueffing) who together are enabling Choroideremia patients access to these trials in Germany.