Neurotech’s Encapsulated Cell Therapy Encelto Approved by FDA for Macular Telangiectasia Type 2
Neurotech expects that the therapy will become available in the United States in June 2025.
Neurotech Pharmaceuticals’ revakinagene taroretcel-lwey (also known as NT-501), an allogeneic encapsulated cell therapy implant, has been approved by the FDA for the treatment of adults with idiopathic macular telangiectasia type 2 (MacTel).1 It is to be marketed under the name Encelto.
Notably, the therapy is the first therapy to be approved for MacTel. Neurotech expects that the therapy will become available in the United States in June 2025.
"This is a historic moment for the MacTel community, as Encelto becomes the first-ever FDA approved treatment for this vision-threatening disease,” Thomas M. Aaberg Jr, MD, the chief medical officer of Neurotech, said in a statement.1 “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 functions by secreting ciliary neurotropic factor (CNTF).2 A tiny hollow cylindrical membrane designed to be implanted into the vitreous cavity of the eye, the therapy encapsulates human epithelial cells genetically engineered to continuously produce CNTF.
Encelto was evaluated in 2 phase 3 clinical trials (protocol A, NCT03316300; protocol B, NCT03319849), data from which were reported in November 2022. The randomized, sham-controlled, multicenter studies were primarily assessing the rate of change in ellipsoid zone area loss, which correlates to photoreceptor loss, from baseline through 24 months as well as the safety of the implant and procedure. It was found that the protocol A trial had a 56.4% rate of reduction (P <.0001) in treated patients and protocol B had a 29.2% rate of reduction (P = .021).
“I have seen the impact that MacTel can have on patients and their quality of life,” investigator Charles C. Wykoff, MD, PhD, of Retinal Consultants of Texas, added to the statement.1 “Now with an FDA approved treatment, I am confident that Encelto will be able to meaningfully slow disease progression for many patients affected by MacTel, allowing them the opportunity to preserve more functional vision over time.”
According to the prescribing information highlights provided by Neurotech, Encelto is contraindicated for those with ocular or periocular infections or known hypersensitivity to endothelial serum free media. Conjunctival hemorrhage, delayed dark adaptation, foreign body sensation, eye pain, suture related complications, miosis, conjunctival hyperemia, eye pruritus, ocular discomfort, vitreous hemorrhage, blurred vision, headache, dry eye, eye irritation, cataract progression or formation, vitreous floaters, severe vision loss, eye discharge, anterior chamber cell, and iridocyclitis constitute the most common adverse events associated with the therapy, having occurred at a rate of at least 2%.
In the Warnings and Precautions section, it is noted that the risk of implantation-related vitreous hemorrhage can be decreased if patients discontinue use of antithrombotic medication before receiving encelto. If vitreous hemorrhage occurs more than a year after implantation of encelto, it may indicate encelto extrusion, and as such an examination is advised, along with subsequent surgical repositioning of encelto if it is found to be indicated. Furthermore, because implantation of encelto has been associated with severe vision loss, infectious endophthalmitis, retinal tears, retinal detachment, vitreous hemorrhage, implant extrusion, cataract formation, suture related complications, and delayed dark adaptation, any signs or symptoms of these adverse events ought to be reported as soon as possible so that any necessary intervention or management can be provided.
