A study in its early stages is a ground breaking moment nevertheless, although it is a very small study and is concerned only with safety considerations in embryonic stem cell therapy.
InLondon, at theMoorfieldEyeHospital, where a parallel trial is in operation, a British man is now undergoing embryonic stem cell research therapy and he is the first European to receive such treatment.
In theUnited Statesstudy arm, both women in the trials suffer from one of the macular degeneration forms that result in retinal cells dying and losing central vision.
The first woman, in her 70s, has dry macular degeneration, a leading cause of vision loss in the West. This form is age-related. The patient could only read 21 letters on a test chart to check her vision, and she is now able to read 28 of the letters.
The second woman suffers from the most common macular degeneration, Stargardt’s disease, which is seen in younger people. Before macular degeneration therapy the patient could see only hand movement and is now able to detect finger movement and more. Both women were treated with the stem cell treatment last July.
At theUniversityofCalifornia,Los Angeles, the Jules Stein Eye Institute reported no safety issues were found in either patient even after four months passed since they were treated.
In each patient, 50,000 RPE—retinal pigment epithelium—cells taken from embryonic stem cells were injected in one eye. This was done so that the vision in the treated eye could be compared to the vision in the untreated eye.
The death of RPE retinal cells and the loss of rod and cone cells underneath that are light receptive cells, causes dry age-related macular degeneration. The same kinds of cells are lost in Stargardt’s disease, but the cause is a genetic defect and it can be detected as early as in a patient’s teens.
The theory in the studies is that the health of the underlying rods and cones will be improved as new RPE cells repopulate the epithelial layer. The ACT—Advanced Cell Technology—was developed by aUnited Statesstem cell company.
One of the authors of the study and chief science officer at ACT, Dr. Robert Lanza, stated that both patients’ vision appears improved after the cells were transplanted, even though it was a low dose, and despite the progressive nature of the disease.
He went on to say that this result is of particular importance because the goal of the therapy would ultimately be treating patients in the early stages of the disease when even better results may be experienced.
He and the other authors pointed out that the study was designed only to test the tolerability and safety of this technique on 24 patients.In the meantime, in the European study, a few of the 12 volunteers have been injected under general anesthesia. It is too soon to tell what the results will be for each patient, but all are hopeful that an upcoming assessment will show improvement in vision.