Magnetic Cell Therapy for Corneal Disease

Magnetic cell delivery is a platform technology that holds promise as a replacement for damaged corneal endothelial cells, reducing the need for corneal transplants, Jeffrey L Goldberg MD, PhD told the Innovators Session of the 2021 ASCRS meeting.

The therapy has recently begun a phase 1b US FDA clinical trial. Dr Goldberg helped develop the magnetic cell delivery system, designed to overcome three key barriers in cell therapy—how to deliver cells to the desired spot, retain them there, and integrate them into surrounding tissues.

EXPANDED DONOR CELLS The treatment starts by expanding human corneal endothelial cells in culture. “A single donor cornea can produce enough cells to treat hundreds of patients, addressing donor supply,” Dr Goldberg said. He credited Shigeru Kinoshita MD, PhD and others with developing techniques supporting endothelial cell expansion and replacement.

The expanded cells then combine with magnetic nanoparticles that coat the cells and get injected into the anterior chamber, Dr Goldberg continued. A magnetic eye patch is then applied for a period of one hour up to overnight. This patch attracts the coated cells to the posterior surface of the cornea, facilitating localisation and integration of the magnetic cells into the endothelial layer.

The treatment could allow general ophthalmologists to identify patients needing endothelial cell treatment, order a treatment kit consisting of the cells and magnetic patch, and treat the patient in their clinic, Dr Goldberg said.

“It addresses the fundamental problem in these diseases of too few endothelial cells. It is a non-surgical procedure, easy to perform, has rapid recovery, gets rid of this donor limitation element, and is safe and repeatable.”

First-in-human trials studied two formulations in 21 patients, mostly with end-stage corneal oedema due to endothelial dysfunction. Even though the patients had long-term scarring, nine out of 21 gained three lines or more of vision, and there were no safety issues after 12 months.

The treatment entered a US-based phase 1b clinical trial for FDA approval with the first patient dosed in July 2021, Dr Goldberg said. The study will include up to 18 patients testing three cell dosages, with and without endothelial cell brushing. There is a plan for a phase 2 study for the most successful dosage.

Dr Goldberg anticipates the therapy will eventually greatly expand the patient population eligible for endothelial treatment, addressing vision loss and significant unmet need around the world.

Jeffrey Goldberg MD, PhD is Professor and Chair of Ophthalmology at the Byers Eye Institute at Stanford University, California, USA. He is a founder and equity partner of Emmecell, the company developing the technology.