New Treatment Restores Healing & Repairs Damage From Neurotrophic Keratitis
By Marguerite McDonald, MD, FACS
Starting this fall, ophthalmologists have a new treatment option for adult patients with moderate to severe neurotropic keratitis.
Cenegermin, sold under the name Oxervate, was approved by the U.S. Food and Drug Administration in August, after the regulator granted priority review status to the breakthrough drug. Cenegermin, which was developed by the Italian drug maker Dompe, is the first drug approved for treatment of this relatively rare condition.
Oxervate is sold in eye-drop form, and the treatment works by restoring the normal healing processes of the eye and repairing corneal damage.
Neurotrophic keratitis is caused by damage to the trigeminal nerve and affects less than five in 10,000 people. While it may be uncommon, the condition can produce serious symptoms, including the loss of corneal sensitivity. In more severe cases neurotrophic keratitis can result in ulcers, melting, and corneal perforations, which can lead to significant vision loss.
Oxervate was studied in 151 patients with neurotrophic keratitis for two eight-week, randomized controlled double-blind studies conducted at multiple centers. In the first study, patients with disease in one eye were studied; the second study involved patients with disease in both eyes and they were treated bilaterally. In both studies, patients were randomly assigned treatment and the effectiveness of Oxervate was compared with drops that did not contain cenegermin. In both studies, patients were given drops in affected eyes six times daily for eight weeks. And, in both studies, 70 percent of patients treated with Oxervate experienced complete corneal healing, while only 28 percent of patients who received an alternate treatment experienced that level of healing.
The most common adverse reactions noted were eye pain, ocular hyperemia, inflammation and increased tear production.
Cenegermin, the active ingredient in Oxervate, is a recombinant version of human nerve growth factor (NGF). NGF was discovered by Dr. Rita Levi-Montalcini, who conducted her initial research secretly in her bedroom after Jews were barred from university work during World War II. Her work earned her a Nobel Prize in 1986.
Cenegermin, a protein naturally produced by the body, facilitates the development, maintenance and survival of nerve cells. It activates receptors, located on the surface of neurons, called tyrosine receptor kinases (Trks). When activated by NGF, the Trks proteins trigger a series of cellular events that stimulate immature neurons to grow axons and survive.
While Oxervate is a welcome addition to the arsenal of treatments available for ocular surface disease, research suggests that this eye drop is just one of the beneficial results of the discovery and increased understanding of the function of NGF. Studies have shown positive benefits of NGF in both the anterior and posterior areas of the eye, as well as suppression of inflammation and even the slowing of age-related memory loss and cognitive decline.
Marguerite McDonald, MD, FACS, with OCLI on Long Island, NY, is clinical professor of Ophthalmology at NYU Langone Medical Center, NY, and clinical professor of Ophthalmology at Tulane University Health Sciences Center, New Orleans, Louisiana.