With a U.S. green light for its encapsulated cell therapy technology in the bag, privately held biotech Neurotech Pharmaceuticals is on the verge of making its commercial debut.
The FDA last week approved (PDF) Neurotech’s cell therapy implant revakinagene taroretcel to treat the vision-robbing neurodegenerative disease macular telangiectasia (MacTel) type 2.
The drug, which will adopt the brand name Encelto, is the first to win the FDA’s blessing in the rare vision disorder, Neurotech said in a release.
In MacTel type 2, small blood vessels at the center of the retina dilate and, in some cases, new blood vessels form under the retina in a process known as neovascularization, according to the American Academy of Ophthalmology. Those blood vessels subsequently bleed or leak fluid, causing the light-sensitive portion of the retina, the macula, to swell or thicken, affecting patients’ central vision.
MacTel type 2, which primarily occurs in middle-aged adults, can also lead to loss of detail vision. The type 2 version of the disease affects both eyes, though not always with the same severity.
Encelto works by utilizing Neurotech’s proprietary encapsulated cell therapy (ECT) platform to continually deliver therapeutic doses of the protein ciliary neurotrophic factor straight to a patient’s retina, which is in turn expected to slow the progression of MacTel.
Neurotech describes its ECT platform as a cell-based gene therapy delivery system designed to provide therapeutic proteins to patients with chronic eye diseases.
The platform itself is made up of a small, semipermeable capsule loaded with allogeneic retinal pigment epithelium (RPE) cells that have been genetically engineered to produce therapeutic proteins.
After the capsule is implanted via a surgical procedure, its semipermeable exterior allows essential nutrients to enter while therapeutic proteins can escape and travel to the retina at the back of the eye, Neurotech explained in its Thursday approval announcement.
While Encelto currently stands alone against MacTel type 2, the drug boasts a clear convenience edge over other eye disorder drugs, which are often given via repeat injections or refillable delivery system implants.
The FDA based its approval decision on the readouts of two late-stage trials that found Encelto significantly slowed the loss of macular photoreceptors in MacTel patients over a 24-month span, Neurotech said.
In results from a pair of replicative phase 3 trials issued in late 2022, Neurotech reported that Encelto—then coded as NT-501—curbed the rate of MacTel progression by 56.4% and 29.2% compared to a simulated treatment through 24 months.
"This is a historic moment for the MacTel community, as Encelto becomes the first-ever FDA approved treatment for this vision-threatening disease,” Neurotech’s chief medical officer, Thomas Aaberg Jr., M.D., said in a statement. “For those who have been affected by MacTel and for all who have supported this journey, today we look forward to a future where vision loss from MacTel may be slowed."
Encelto is slated to become Neurotech’s first commercial product. The company plans to launch the product in the U.S. starting in June.