Embryonic stem cells to treat severe eye diseases?

El Mundo issue, wich we  consider ethically questionable beacause the results of uncompleted clinical trials are assumed to be reliable, since this can create unfounded expectations


On 15 October 2014, Spanish newspaper El Mundo published a report, with a prominent editorial, discussing a recent article published online in medical journal The Lancet (doi.org/10.1016/S0140-6736(14)61376.3) on the same date.

The facts

The article published in The Lancet described how retinal epithelium cells were obtained using embryonic stem cells (eSC), which were then transplanted into nine patients with Stargardt’s macular dystrophy and a further nine patients with age-related macular degeneration (AMD). The patients were followed-up for 22 months with the relevant ophthalmological examinations. The trials were recorded on the Clinical Trials.gov website: trial number NET0134500 for Stargardt’s dystrophy patients, and NCT01344993 for AMD patients.

This was a phase 1/2 clinical trial, so its aim was to evaluate the safety and tolerability of treatment, not the clinical results. There was no evidence of adverse proliferation or rejection. The adverse effects found were attributed to the vitreoretinal surgery and immunosuppressive therapy. Although the aim of the study was not to assess the clinical effects, the investigators reported that vision was recovered in ten patients (in the treated eye), remained unchanged in seven, and decreased in one, while the vision in the patients’ untreated eye remained similar to the baseline values.

The authors stated that this was the first time that such an experiment had been conducted, and that it had been shown to be safe, with survival of the cell implant and possible biological activity of the transplanted stem cell progeny.

The views, opinions and positions expressed by these authors and blogs are theirs and do not necessarily represent that of the Bioethics Research Library and Kennedy Institute of Ethics or Georgetown University.