Preliminary phase 1b data on Astellas Pharma Inc’s ASP7317 for advanced geographic atrophy (GA) secondary to age-related macular degeneration (AMD) dives into new safety and tolerability findings.
The results were presented last week during the 2026 Association for Research in Vision and Ophthalmology (ARVO) annual meeting in Denver, Colorado.
Let’s dive into this cell therapy.
ASP7317 is an investigational retinal pigment epithelium (RPE) cell therapy derived from human embryonic stem cells (hESCs) and administered via subretinal injection to replace damaged RPE cells—potentially improving visual function.
- Note: The candidate is the flagship program under Astellas’s Blindness and Regeneration pipeline, most of which is currently in the preclinical testing stage.
Next up: this phase 1 study.
What it is: An open-label, multicenter, dose escalation phase 1b trial (NCT03178149) evaluating the safety and tolerability of ASP7317 in patients 50+ years with GA.
Three different doses (low, medium, or high number of cells) of the candidate are being evaluated across two groups, wherein successive cohorts of patients (three participants each) will be given escalating doses, making up a total of 6 cohorts between Groups 1 and 2.
The inclusion criteria for both groups are as follows:
- Group 1: Individuals with severe vision loss
- Visual acuity: Defined as best-corrected visual acuity (BCVA) between light perception and ≤23 Early Treatment Diabetic Retinopathy (ETDRS) letters (cohort 1) or BCVA score between 15 (≥20/500) and 37 (≤20/200) ETDRS letters (cohorts 2 and 2) at the screening visit
- GA area: Total GA area ≤30.5 mm2 (≤12 disc areas [DA])
- Group 2: Individuals with moderate vision loss
- Visual acuity: BCVA score between 38 (>20/200) and 65 (≤20/50) ETDRS letters during the screening visit
- Difference in mean mesopic sensitivity ≤2 dB between two tests at screening; if not ≤2 dB, a third test may be conducted and mean values between the second and third assessments must be ≤2 dB
- GA area: Total GA area ≥2.54 mm2 and ≤20.4 mm2 (≥1 and ≤8 DA, respectively) and must reside completely within the fundus autofluorescence imaging field
- Visual acuity: BCVA score between 38 (>20/200) and 65 (≤20/50) ETDRS letters during the screening visit
Primary outcome measures?
Safety and tolerability were as measured:
- Safety assessed by incidence, frequency, and severity of treatment emergent adverse events (TEAEs) and serious AEs (SAEs)
- Safety evaluated by AEs of special interest (see here)
- Number of participants with cellular graft failure or rejection
- Incidence of cellular graft failure or rejection
And the secondary outcome measures?
A few to note, such as mean change from baseline in:
- Area of GA (mm2) in study and fellow eye
- Area of GA (mm2) in study and fellow eye
- Square root transformation of GA area in study and fellow eye
- BCVA score in study and fellow eye
See here for the complete list.
Let’s finally get to the data.
The reported findings came from 14 patients with advanced GA; enrollment was limited to patients with severe vision impairment and GA lesions measuring 30.5 mm² or smaller.
Patients were divided into low- (n=3), medium- (n=5), and high-dose (n=6) cohorts, with patients undergoing pars plana vitrectomy and subsequent subretinal transplantation of ASP7317.
And overall?
At 26 weeks, treated eyes demonstrated improvements in BCVA across all ASP7317 dose cohorts, while untreated fellow eyes generally declined.
In addition: Mean BCVA change from baseline in treated eyes was as follows:
- Low-dose cohort: +10.5 letters
- Fellow untreated eye: -4.0 letters
- Medium-dose cohort: +7.25 letter
- Fellow untreated eye: -5.65 letters
- High-dose cohort: +4.25 letters
- Fellow untreated eye: +2.56 letters
Any reported improvements in visual acuity?
At 52 weeks, visual gains appeared to persist in the cohorts with available follow-up data, as mean BCVA change from baseline was:
- Low-dose cohort: +5.5 letters
- Fellow untreated eye: -2.5 letters
- Medium-dose cohort: +9.08 letter
- Fellow untreated eye: -5.75 letters
Note: Patients in the high-dose cohort had not yet reached the 52-week follow-up time point.
Anything else?
GA lesion size appeared generally stable in treated eyes, with spectral-domain optical coherence tomography (SD-OCT) imaging suggesting preservation of outer retinal structures, including the ellipsoid zone.
Comparatively: Fellow untreated eyes typically demonstrated stable or progressive degeneration consistent with unchanged or worsening visual function.
Last but not least: the safety data.
No signs of immune rejection, abnormal cell growth, transplant failure, inflammation inside the eye, or pressure-related complications were reported.
Epiretinal membrane progression to proliferative vitreoretinopathy occurred in one patient in the low-dose cohort.
Any other news from Astellas?
Most recently: In October 2025 the open label extension trial of the GATHER2 study demonstrated that IZERVAY continued to reduce GA lesion growth for up to 3.5 years, and earlier intervention resulted in greater protection of the retinal tissue area.
Plus: This study’s estimated primary completion is slated for June 30, meaning we are likely to see more data coming in soon.