Just 5 months after receiving regulatory approval from the FDA, Neurotech Pharmaceuticals, Inc. shared that the first procedure for ENCELTO (revakinagene taroretcel-lwey) has been performed for idiopathic Macular Telangiectasia Type 2 (MacTel).
Notably: This marks the first procedure of the first-ever FDA-approved treatment for MacTel.
First things first: Talk about MacTel.
This is a rare, age-related bilateral neurodegenerative retinal disease that leads to a gradual deterioration of central vision in adults aged 40+.
How: By causing abnormalities in capillaries of the fovea or perifoveal regions linked to a loss of outer nuclear layers and the ellipsoid zone—which then progress to either:
- “Cystic cavitation-like changes in all retinal layers”
- Development of full-thickness macular hole (or subretinal neovascularization) in later stages
The disease is divided into three types:
- Type 1: Congenital and unilateral (uncommon)
- Type 2: Acquired and bilateral (most common, with average patient age of 63)
- Type 3: Rare and not yet clinically understood
And ENCELTO targets Type 2?
Indeed it does. But to understand ENCELTO, an understanding of Neurotech’s Encapsulated Cell Therapy (ECT) platform is needed.
About the ECT platform: This enables continuous production and delivery of targeted therapies—both singularly and in combination—to the retina for the long term.
- See here for details on how the platform targets disease (plus a visual of the delivery process of those specific therapeutic proteins to provide treatment).
- Its basis: The NCT-200 cell line, which operates in low oxygen and nutrient conditions, can be genetically manipulated, is customizable, and can be genetically engineered to produce “clinically relevant levels of therapeutic protein”
Now explain ENCELTO.
As an ECT, ENCELTO is an ocular implant that relies on Neurotech’s ECT platform to deliver therapeutic doses of ciliary neurotrophic factor (CNTF) into the retina to slow disease progression.
- Why CNTF? Because the cytokine is known to have a neuroprotective effect, protecting against photoreceptor loss in MacTel.
Product details: The single-dose implant (per affected eye) is intended for surgical intravitreal (IVT) implantation by a vitreoretinal surgeon in an outpatient procedure.
- The dosage: 200,000 to 440,000 allogeneic RPE cells expressing recombinant human CNTF (rhCNTF).
Gotcha. So what do we know about this first implantation?
Specifically, Neurotech announced the “first commercial manufacturing, shipment, and surgical procedure” of ENCELTO was performed in Houston, Texas.
Specifically: By Charles C. Wykoff, MD, PhD, of Retinal Consultants.
- “For the first time, we can offer a valuable and durable treatment option for patients, one that slows their loss of photoreceptors and maintains more visual function over time,” Dr. Wykoff stated.
No details were released as to the patient or date of the implantation.
Alrighty then. And any specific postop care to follow?
For postop care, patients should:
- Use a topical solution of 1 drop, four times a day (QID) for 7 days
- Use a steroid drop taper of prednisolone acetate 1% (or equivalent) starting the day after surgery with the following schedule:
- 1 drop QID for the first 7 days
- 1 drop three times a day (TID) for the next 7 days
- 1 drop two times a day (BID) for the next 7 days
- 1 drop once a day for the last 7 days
How about possible side effects or precautions to be aware of?
A few precautions are advised for a patient immediately post-implantation.
As for potential side effects:
- Endophthalmitis
- Retinal tear and detachment
- Vitreous hemorrhage
- Implant extrusion
- Suture-related issues
- Temporary or permanent vision loss
- Accelerated cataract formation
- Delayed dark adaptation
A note on dark adaptation: If this develops, it is unknown how long symptoms may last. As such, patients should take precautions (see here).
See here for more common side effects (including eye redness, irritation, dryness, and discharge).
And when should a doctor be called?
If a patient begins experiencing sudden changes in their vision, such as:
- An increase in floaters
- Appearance of “spider webs”
- Flashing lights
- Sensitivity to light
- Vision or visual field loss
- Progressively worsening pain
- Increasing discharge/drainage from the eye
Immediate care from an eye surgeon is advised.