Luxa Biotechnology LLC released positive findings from its first-in-human (FIH) phase 1/2a clinical trial evaluating its proprietary retinal pigment epithelium (RPE) cell therapy for dry age-related macular degeneration (AMD).
The data was presented over the weekend during the annual Wills Eye Conference in Philadelphia, Pennsylvania.
Start with this company.
Based in New Jersey, Luxa was formed as a joint venture between the Albany, New York-based Neural Stem Cell Institute (NSCI) and Y2 Solution (a Korean technology company).
The clinical-stage biotechnology company’s purpose: Developing a novel adult RPE stem cell therapy for dry AMD.
- To note: This investigational candidate was originally developed and licensed by the NSCI.
The goal: Luxa is looking to prevent vision loss by transplanting new RPE cells under the retina—ideally resulting in improved vision for patients diagnosed with dry AMD and geographic atrophy (GA).
Backtrack to NCSI for a moment.
Originally founded in 2005 by Jeffrey Stern, PhD and Sally Temple, PhD—Luxa’s CEO and chief scientific officer—NCSI is a 501c3 nonprofit known as the first independent stem cell research institute in the United States.
Among its accomplishments since launching, the institute has:
- Published 80+ publications on neurodegenerative disease
- Received three patients (with more on the way)
- Created and launched three entities:
- Nuracell, a nonprofit core facility that distributes stem cell lines/models to benefit neural stem cell research
- StemCulture, LLC, a biotechnology company that sells stem cell reagents
- Luxa Biotechnology
Talk more about its treatment process.
The basis for this “disease-modifying approach" starts with the early loss of RPE cells (during AMD) that typically protect the overlying photoreceptor cells within the central area of the retina.
Luxa’s approach: Involves replacing those lost RPE cells to improve vision.
And how is this done, exactly?
Through an adult stem cell source of RPE cells (RPESC) already located in the human eye’s RPE layer and reported to produce millions of new healthy RPE cells in tissue culture.
- Specifically: These RPESC “exhibit critical functions that support retinal health, including phagocytosis of the photoreceptor outer segments and the secretion of beneficial growth factors,” according to Luxa.
In other words: New RPE cells can be made from stem cells and then injected under the retina to replace damaged RPE cells.
So the investigational candidate is called ….
Its name: RPESC-RPE-4W.
- What it is: A cell product derived from adult RPESC that generates RPE cell progeny (RPESC-RPE).
Its potential: To become the first FDA-approved therapy for treating advanced dry AMD.
- Take note: While not previously tested in humans (hence this FIH trial), reports have noted the stem cell-based replacement therapy “restores vision in animal models of AMD.”
And its regulatory status so far?
Back in 2020: The NSCI advanced RPESC—with funding from the National Eye Institute (NYE) and the New York Stem Cell Science Initiative (NYSTEM)—to a “successful IND (investigational new drug) application to the FDA.”
And more recently: RPESC-RPE-4W was granted Regenerative Medicine Advanced Therapy (RMAT) designation just last month.
- Click here for a rundown on this dedicated, expedited FDA program (and here for how it differs from Breakthrough Therapy Designation designation).
Got it. Now, let’s talk about this study.
Initiated in 2022, this ongoing open-label, dose-escalation, interventional FIH trial (NCT04627428) is currently evaluating the safety and tolerability of RPESC-RPE-4W among patients diagnosed with dry AMD.
The details:
- Participants: 18 dry AMD patients (aged 55+)
- Setup: Participants are separated into three separate groups to receive one of three different doses (low, medium, and high) of RPESC-RPE-41:
- Group 1: Single dose of 50,000 RPESC-RPE-4W cells in the eye (n = 6)
- Group 2: Single dose of 150,000 RPESC-RPE-4W cells in the eye (n = 6)
- Group 3: Single dose of 250,000 RPESC-RPE-4W cells in the eye (n = 6)
- The outcome measures (measured at 24 months):
- Primary: Safety and tolerability of RPESC-RPE-4W transplantation, as determined by factors such as:
- Decrease in visual acuity (VA) of Early Treatment Diabetic Retinopathy Study (ETDRS) letters from baseline.
- See here for more criteria
- Decrease in visual acuity (VA) of Early Treatment Diabetic Retinopathy Study (ETDRS) letters from baseline.
- Secondary:
- Change in mean best-corrected visual acuity (BCVA)
- Loss of ≥10 decibels (dB) of ten-degree average visual sensitivity microperimetry
- Change in GA lesion area
- Evidence of structural changes
- Primary: Safety and tolerability of RPESC-RPE-4W transplantation, as determined by factors such as:
And what is this new data based on?
That would be post-implant clinical outcomes from the six patients in Group 1 (low-dose cohort).
Per the company: Each participant received a 50,000-cell suspension of RPESC-RPE-4W implanted under the macula.
The analysis: Outcomes were measured for two subgroups within this cohort:
- Group I: Worse-seeing patients over 12 months
- Group II: Better-seeing patients over 3 months
So what was found?
Focusing on BCVA, Luxa reported “substantial” improvements.
- Group I: Average gain of +21.67 ETDRS letters at 12 months
- Group II: +3.3 ETDRS letter improvement at 3 months
Why these numbers matter: While the FDA typically considers a loss or gain of 15+ ETDRS letters to be a clinically significant change, an improvement of at least 5 letters can also be clinically relevant—particularly for patients with poor VA.
- In this situation: The company noted that “even a 5- to 10-letter improvement can translate into a real-world functional benefit for patients, such as improved reading ability, better recognition of faces, and enhanced mobility.”
Go on …
Luxa added that the positive outcomes of patients from the worse-seeing group (Group II)—referred to as those with the “most severe baseline vision impairment” who “achieved the most significant vision restoration”—reinforces the potential of RPESC-RPE-4W for addressing advanced dry AMD.
What about in the better-seeing group?
Interestingly, those patients saw smaller—“yet still clinically relevant”—improvements that counteracted the expected natural decline in dry AMD progression, Luxa noted.
Are there any potential benefits for earlier-stage AMD?
Yes … the data also supported the therapeutic’s potential for "reversal of disease trajectory” by preserving vision in patients with this earlier stage of the disease—“possibly delaying or even preventing progression to severe impairment,” the company stated.
Plus: According to Jeffrey Stern, MD, PhD, Luxa’s chief medical officer, the findings "highlight the promise of our approach in restoring vision, while the modest improvements in better-seeing individuals suggest a beneficial impact in slowing disease progression.
Nice! So what’s next for this candidate?
Next up: testing of the two other higher-dose RPESC-RPE-4W cohorts (150,000 and 250,000 RPESC-RPE-4W cells).
As for timing: ClinicalTrials.gov reports the FIH is expected to conclude in December 2026; so we’ll likely (hopefully?) be hearing updated findings from the company between now and then.
As always, stay tuned!