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Neurotech's NT-501 Implant Slows Vision Loss in Patients with Geographic Atrophy Associated with Dry AMD as Reported in PNAS

LINCOLN, R.I.--(BUSINESS WIRE)--Apr 5, 2011 - Neurotech Pharmaceuticals, Inc., today announced that it was reported in the Proceedings of the National Academy of Sciences (PNAS) (online March 28, 2011) that its product candidate NT-501 slowed progression of vision loss in patients with geographic atrophy (GA) associated with dry age-related macular degeneration (AMD) in a Phase 2 study. NT-501 is an intraocular implant that consists of human cells genetically modified to secrete ciliary neurotrophic factor (CNTF) - a nerve growth factor capable of rescuing and protecting dying photoreceptors. GA is a condition that destroys sharp central vision, often resulting in serious vision loss to one or both eyes, for which there is no available treatment.

The Phase 2 study was a multi-center, double-masked, sham-controlled, dose-ranging study in 51 subjects with GA. Subjects were randomly assigned to receive either a high- or low-dose NT-501 implant or sham surgery. The primary study endpoint was change in best corrected visual acuity (BCVA) at 12 months. The study results demonstrated a dose-dependent increase in retinal thickness suggesting increased photoreceptor metabolic activity. This increase was followed by visual acuity stabilization (loss of fewer than three lines of vision, or 15 letters) of 96.3% in the high-dose group compared to 83.3% in the low-dose group and 75.0% in the sham group. In a sub-group analysis of subjects with better vision at base line (20/63 or better), 100% of the high-dose group (n = 10) maintained visual acuity stabilization compared to 55.6% (p = 0.033) in the combined low- and sham-treated groups (n = 9). In this sub-group analysis, there was a 0.8 mean letter gain in the high-dose group compared to a 9.7 mean letter loss in the combined low- and sham-treated groups. Overall, there were no serious adverse events reported and the surgical procedures were well tolerated. The study results were originally reported by the Company in March 2009.

The study's lead author and one of its clinical investigators, Dr. Kang Zhang, Professor of Ophthalmology & Human Genetics, Shiley Eye Center and Director of the Institute for Genomic Medicine, University of California, San Diego commented, “The study findings are very promising since both structural and functional improvements were demonstrated in a disease that is currently untreatable. These results support the initiation of larger confirmatory studies of NT-501 in patients with GA.”

Paul Sieving, MD, PhD, Director of the National Eye Institute and Principal Investigator of Neurotech's Phase 1 study of NT-501 in retinitis pigmentosa, commented that, “The results of this Phase 2 study suggest that CNTF delivered by the ECT platform may be a useful approach to slow the progression of vision loss in GA patients, and warrant further study in a larger trial of patients exhibiting early onset of this condition.”

Ted Danse, Chief Executive Officer of Neurotech stated, “These results in GA demonstrate the significant opportunity of NT-501 to fill a much needed treatment void for sight-robbing retinal degenerative diseases. The data also provide further validation of our proprietary ECT technology and strongly support the introduction of additional product candidates from the platform.”

About Dry AMD/ Geographic Atrophy (GA)

Age-related macular degeneration (AMD) is a chronic progressive disease of the macula that results in the loss of central vision. It is the leading cause of blindness in elderly people in the developed world. There are two forms of AMD – dry and wet. Dry AMD is the most common form of AMD representing approximately 90% of all AMD cases. In its advanced stages dry AMD can lead to the degeneration of photoreceptors, those cells of the retina responsible for fine central and color vision, and retinal pigment epithelial cells, those cells responsible for nourishing photoreceptors, resulting in a chronic condition called geographic atrophy (GA). There are currently no approved GA therapies for the nearly 1 million individuals affected in the United States.

About NT-501

NT-501 is one of Neurotech's lead product candidates under development and consists of encapsulated human cells genetically modified to secrete ciliary neurotrophic factor (CNTF). CNTF is a nerve growth factor capable of rescuing dying photoreceptors and protecting them from degeneration. NT-501 is designed to continually deliver a therapeutic dose of CNTF into the back of the eye in a controlled, continuous basis by means of the Company's proprietary Encapsulated Cell Therapy (ECT) platform. Delivery via ECT bypasses the blood-retinal barrier and overcomes a major obstacle in the long-term treatment of retinal disease.

About Encapsulated Cell Therapy

Neurotech's core technology platform is Encapsulated Cell Therapy (ECT), a unique technology that allows for the long-term, sustained delivery of therapeutic factors to the back of the eye. ECT implants consist of human cells that have been genetically modified to produce a specific therapeutic protein and encapsulated in a semi-permeable hollow fiber membrane. The diffusive characteristics of the hollow fiber membrane are designed to promote long-term cell survival by allowing the influx of oxygen and nutrients while simultaneously preventing direct contact of the encapsulated cells with the cellular and molecular elements of the immune system. The cells continuously produce the therapeutic protein which diffuses out of the implant at the target site. ECT enables the controlled, continuous delivery of therapeutic factors directly to the retina, thereby bypassing the blood-retina barrier.

About Neurotech Pharmaceuticals, Inc.

Neurotech is developing sight-saving therapeutics for the treatment of chronic retinal diseases. NT-501, one of the Company's lead product candidates, is currently in late-stage clinical development for retinitis pigmentosa (RP) and advanced dry age-related macular degeneration (dry AMD). The Company's portfolio of product candidates also includes treatments for wet AMD, including NT-503 that delivers a VEGF antagonist. All of Neurotech's development programs are based on the Company's proprietary Encapsulated Cell Therapy (ECT). ECT uniquely enables the controlled, continuous delivery of biologics directly to the back of the eye, thereby overcoming a major obstacle in the treatment of retinal disease. To learn more, please visit our web site at

Contact: Neurotech Pharmaceuticals, Inc.
Rich Small, 401-495-2403
Vice President, Chief Financial Officer


Posted: April 2011