Applications

Pixium to begin US trials of 'bionic' retina

05 Jan 2018

FDA approval to evaluate 'PRIMA' implant in up to five patients with atrophic dry age-related macular degeneration.

Up to five patients who have lost their sight because of atrophic dry age-related macular degeneration (AMD) are set to be fitted with a “bionic” retinal implant designed to restore some basic visual function.

Following US Food & Drug Administration (FDA) approval of Pixium Vision’s “PRIMA” device, the France-based company says that the clinical feasibility study at the University of Pittsburgh Medical Center should begin in the first half of this year.

The leading cause of blindness in the developed world, AMD impacts the central area of vision by damaging the area of the retina – the macula – that has the highest concentration of cone cells and is responsible for high-resolution, color vision.

Among those battling the condition is the Oscar-winning actor Dame Judi Dench. The 82-year-old is reported to suffer from the “wet” form of AMD in one eye, and from the slower-acting dry-AMD in the other.

First US approval

Pixium’s FDA approval comes just a few months after health authorities in France permitted a similar trial in the country, with five patients set to receive the implant at a Paris hospital.

CEO Khalid Ishaque said in a company release: “This first approval in the US will allow Pixium Vision to commence a feasibility study of the PRIMA device and follows a thorough review by the FDA. It also highlights the FDA’s recognition of PRIMA’s innovative potential to address the significant unmet need to treat atrophic dry-AMD.”

Although it is slower to take hold than the wet form of the condition, dry-AMD is still a major cause of irreversible vision loss, and thought to affect approximately 4 million people globally, with no current effective treatment.

“Alongside the ongoing clinical trial in France, the feasibility study in the United States marks a significant milestone for Pixium Vision with the mission to create a world of bionic vision for those who have lost their sight,” Ishaque added.

Clinicians at the University of Pittsburgh Medical Center will recruit up to five patients with vision loss from dry-AMD. The primary end-point is restoration of visual perception as well as safety after a year, with a longer-term follow-up after three years.

External glasses and camera

The PRIMA system, which uses external glasses in combination with the implant, is designed to provide partial restoration of the patient's visual function through electrical stimulation of retinal neurons, with the sub-retinally implanted stimulator replacing part of the degenerated photoreceptors.

PRIMA’s micro-photovoltaic chip measures just 2x2 millimeters and is only 30µm thick, but is equipped with 378 electrodes. Implanted under the retina via what is described as a less invasive surgical procedure than other “bionic” devices, it converts a pulsed near-infrared light signal received from a camera integrated within the external glasses into electrical signals that are transmitted to the brain via the optic nerve.

Based on technology originally conceived at Stanford University, PRIMA is one of a handful of retinal implants being tested for their effectiveness. Others have been developed by Germany-based Retina Implant and the US company Second Sight.

Listed on the Euronext Paris stock exchange, Pixium raised €15 million in venture finance in 2013 before completing a €34.5 million initial public offering of stock the following year.

Its technology is also being aimed at treating vision loss caused by the condition retinitis pigmentosa.