PARIS - Neurotech SA reported that tests on animal models of pigmentary retinopathy demonstrated the efficacy of its Encapsulated Cell Technology (ECT), opening the way to treating numerous diseases of the eye that result in blindness.

At the same time, it has shown that it can successfully produce implants to GMP standards and manipulate them in vivo with no ill effects.

On the strength of these results, the Foundation Fighting Blindness (FFB) is providing Neurotech with logistical support for the conduct of further tests of this implant in large animal models, with a view to obtaining FDA permission to start human clinical trials. Neurotech CEO Tom Shepherd told BioWorld International that he anticipates having the product in clinical development in the U.S. by the end of 2001. He added that the FFB was supplying the dogs being used in the second series of animal tests, which are already under way, and had arranged for Neurotech to receive technical assistance from academic institutions that receive research funding from the foundation.

The initial animal tests entailed implanting in the eye a capsule containing cells producing a neurotrophic factor that protects the eye's photoreceptors from degeneration. The capsule was implanted in the vitreous body, with the other eye serving as a control. The results showed that there was a statistically significant degree of protection against retinal degeneration in the treated eye relative to the untreated one. After seven weeks in vivo, the cells were removed without any detectable harmful effects. It also was found that the cells contained in the implant remained viable and continued to secrete the therapeutic protein.

ECT is a proprietary technology of Neurotech, which purchased the industrial property from CytoTherapeutics Inc. in January. It entails placing in a small capsule cells that have been genetically modified to produce large quantities of a given neurotrophic factor. The capsule is composed of a semipermeable membrane that allows oxygen and nutritive substances to pass through but protects the modified cells from the patient's immune system. It ensures that the cells produce the therapeutic protein at a constant rate.

Neurotech, which is based in France's national biotechnology science and business park at Evry and works in cell therapies for diseases of the eye and the brain, has adapted and optimized this technology for the delivery of therapeutic proteins to the eye.