Externally Refilled Eye Implant to Effectively Prevent Common Blindness


San Francisco-based biotechnology company Genentech developed the Port Delivery System that incorporates an implanted drug reservoir

Age-related Macular Degeneration (AMD) is major cause of blindness among geriatric population across the world. The ‘wet’ form of disease is responsible for around 90% of all cases of AMD-related severe vision loss. In wet AMD, abnormal blood vessels growing beneath the retina cause its center section (the macula) to lift up and pull away from its base, leading to a loss of central vision. A drug known as Lucentis was reported to reduce this particular process with prevented blindness in around 90% of test subjects in clinical trials. An experimental eye implant may offer treatment option for such disorder.

The Port Delivery System is based on a device, which is slightly longer than a rice grain. The device is permanently implanted into the eye where it slowly releases medication from its integrated drug reservoir. The reservoir can be refilled at a clinic via a circular port on the end of the device, which appears as a small dot on the surface of the eye beneath the eyelid. Efficiency of Port Delivery System was examined by conducting a multi-center randomized trial, which enrolled 220 patients who had underwent implant surgery. It was observed that the device treated wet AMD as effectively as the conventional injections. However, patients were required to go for a median period of 15 months before requiring a refill.

Although there were some side effects to the initial implantation surgery, the system was found to be overall safe. The system is expected to be available for general use within three years. “Fewer injections and office visits is exciting,” said study leader Dr. Carl D. Regillo, from Philadelphia’s Wills Eye Hospital. “But more importantly, we think it will translate into better visual outcomes because in the real world, patients get less treatment than they need. If you’re a week or two late for a visit from time to time, you may have a decline in vision, and you can’t always recover from that.”


About Author

Bill Carr is a Senior Editor at Plains Gazette, based in Austin. Previously he has worked for FOX Sports and MSNBC's "Morning Joe." he is a graduate of the Annenberg School at the University of Southern California. You can reach Bill via email or by phone