Bold claims from stem cell treatment but caution advised

A recent television news article hailed a stem cell treatment as a cure for macular degeneration. MDNZ has received many enquiries about the treatment. Here is an update on that treatment.

The treatment consists of incorporating stem cells from human embryos onto a synthetic backing membrane and surgically inserting this underneath the macula (central part of the retina). The stem cells had been allowed to develop into RPE cells and these cells support the photoreceptors (light capturing cells in the retina).

Two patients with advanced macular degeneration (MD) have already been treated and permission has been given for a total of 10 patients to undergo treatment. The 2 patients gained 21-29 letters on the vision chart effectively gaining 4-6 lines of vision. Whilst this gain is impressive the patients have reported troublesome distortion and dimmer vision.

The treatment relies on using immunosuppression in the form of local steroids inside the eye to prevent rejection. There were several adverse events that occurred, one of which was a retinal detachment that required further surgery to correct. Fortunately, the patient retained their vision.

There are several risks with stem cell treatments such as rejection, tumour formation, uncontrolled proliferation of cells and the development of stem cells into different cell types that don’t belong in the eye.

The trial results are encouraging but the reality of this as a routine treatment is still many years away. It is important to realise it is not a curative procedure, but it is encouraging to see new regenerative technology advancing the fight against sight threatening vision loss in MD.