NCT07734064

Brief Summary

Macular dystrophies are a group of inherited eye conditions that affect the macula. The macula is in the center of the retina, the light sensitive part at the back of the eye. In people with macular dystrophies, some of the cells in the macula gradually stop working and may die over time. This leads to loss of central vision, which can make it harder to read, recognize faces or see fine details. What's seen out of the corner of the eye (peripheral vision) is mostly unaffected. Stargardt disease (STGD) is a type of macular dystrophy which is caused by 1 faulty gene (ABCA4). Vision loss most typically begins in childhood or teenage years but may also develop in adulthood. As well as STGD, there are other macular dystrophies that look very similar to STGD and are called STGD-like macular dystrophies. These are caused by many other different genes. Together, STGD and STGD-like conditions can be called STGD-type macular dystrophies. This is an early development study of ASP2020 in adults, teenagers, and children with STGD-type macular dystrophies. ASP2020 are human stem cells which have been changed into cells found in the macula. In this study ASP2020 will be given to people for the first time. The main aim of the study is to check the safety of ASP2020 and how well people tolerate it. Other aims are to learn if people have an immune reaction to ASP2020, and if there are signs that the stem cells replace damaged cells in the retina, and vision improves for people with STGD-type macular dystrophies. ASP2020 will be given as a single injection into the eye, under the retina. This requires a surgical procedure where the person is put to sleep by a general anesthetic. At the end of surgery, a steroid will be injected into the eye to reduce any swelling. The study has 2 parts. In Part 1, different small groups will receive a lower to higher dose of ASP2020. This is done to find a suitable dose to use in Part 2. The adults will receive the lower dose and higher dose before the teenagers. There will be a 6-month gap between the last adult receiving the lower dose of ASP2020 and the first teenager receiving the same lower dose. This will also happen for the last adult receiving the higher dose of ASP2020 and the first teenager receiving the higher dose of ASP2020. Any medical problems will be recorded for each dose in each group. Children will not receive ASP2020 in Part 1. In Part 2, different groups of adults, teenagers and children will receive the most suitable dose of ASP2020 worked out from Part 1. People will be in the study for about 1 year and they will visit the clinic several times. In both parts of the study, safety checks will be done at each visit, and the study doctors will continue to check for any medical problems throughout the study. Various eye tests and eye imaging will be done throughout the study. Blood tests will also be done at some of the visits during the study.

Trial Health

65
Monitor

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
30

participants targeted

Target at P25-P50 for phase_1

Timeline
39mo left

Started Jul 2026

Typical duration for phase_1

Status
not yet recruiting

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

First Submitted

Initial submission to the registry

July 15, 2026

Completed
14 days until next milestone

First Posted

Study publicly available on registry

July 29, 2026

Completed
2 days until next milestone

Study Start

First participant enrolled

July 31, 2026

Completed
3.2 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

September 30, 2029

Expected
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

September 30, 2029

Last Updated

July 29, 2026

Status Verified

July 1, 2026

Enrollment Period

3.2 years

First QC Date

July 15, 2026

Last Update Submit

July 24, 2026

Conditions

Keywords

Macular DystrophiesStargardt typeABCA4 related STGDSTGD-like macular dystrophiesSafetySTGDSTGD-likeSTGD-type

Outcome Measures

Primary Outcomes (6)

  • Number of participants with treatment-emergent adverse events (TEAEs)

    An adverse event (AE) is defined as any untoward medical occurrence in a patient or clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. TEAEs are defined as an AE observed after administration of ASP2020 or pre-existing AE that worsen in severity or frequency following administration of ASP2020.

    Up to 52 weeks

  • Number of participants with serious adverse events (SAEs)

    An SAE is defined as any untoward medical occurrence that, at any dose results in death, is life-threatening, requires inpatient hospitalization or prolongation of existing hospitalization, results in persistent or significant disability/incapacity, is a congenital anomaly/birth defect, or other medically important events.

    Up to 52 weeks

  • Number of participants with adverse events of special interest (AESIs)

    AESIs include, but are not limited to, the following: * Ectopic, excessive, or aberrant cell growth of ASP2020, including proliferative changes * Immune-mediated reactions, including unexpected or clinically significant inflammatory responses * Any new diagnosis of malignancy * Any clinically significant AEs possibly or definitely related to ASP2020 * Clinically significant AEs related to the surgical administration procedure

    Up to 52 weeks

  • Number of participants with greater than or equal to 15 letter loss in best corrected visual acuity (BCVA) from baseline

    BCVA will be measured from the Early Treatment of Diabetic Retinopathy Study (ETDRS) letters chart.

    Up to 52 weeks

  • Number of participants with significant changes in vital signs from baseline

    Number of participants with significant changes in vital signs from baseline will be reported.

    Up to 52 weeks

  • Number of participants with significant changes in laboratory values from baseline

    Number of participants with significant changes in laboratory values from baseline will be reported.

    Up to 52 weeks

Secondary Outcomes (14)

  • Change from baseline in BCVA

    Baseline and week 26, 52 or Early Termination (ET) visit whichever occurs first

  • Change from baseline in low luminance visual acuity (LLVA)

    Baseline and week 26, 52 or ET visit whichever occurs first

  • Change from baseline in Minnesota Reading Acuity Chart (MNREAD) parameters

    Baseline and week 26, 52 or ET visit whichever occurs first

  • Change from baseline in mesopic macular sensitivity

    Baseline and week 26, 52 or ET visit whichever occurs first

  • Change from baseline in central retinal thickness (CRT)

    Baseline and week 26, 52 or ET visit whichever occurs first

  • +9 more secondary outcomes

Study Arms (6)

Part 1 Dose Escalation: Adult - Low Dose

EXPERIMENTAL

Adult participants will receive a single low dose of ASP2020 on Day 1, administered by subretinal injection as part of a surgical procedure, followed by triamcinolone acetonide as adjunct treatment by posterior sub-Tenon injection.

Drug: ASP2020

Part 1 Dose Escalation: Adult - High Dose

EXPERIMENTAL

Adult participants will receive a single high dose of ASP2020 on Day 1, administered by subretinal injection as part of a surgical procedure, followed by triamcinolone acetonide as adjunct treatment by posterior sub-Tenon injection.

Drug: ASP2020

Part 1 Dose Escalation: Adolescent - Low Dose

EXPERIMENTAL

Adolescent participants will receive single low dose of ASP2020 by subretinal injection on Day 1 followed by triamcinolone acetonide as adjunct treatment by posterior sub-Tenon injection.

Drug: ASP2020

Part 1 Dose Escalation: Adolescent - High Dose

EXPERIMENTAL

Adolescent participants will receive single high dose of ASP2020 by subretinal injection on Day 1 followed by triamcinolone acetonide as adjunct treatment by posterior sub-Tenon injection.

Drug: ASP2020

Part 2 Dose Expansion: Adult with macular dystrophies

EXPERIMENTAL

Adult participants will receive single optimal dose of ASP2020 established in part 1 by subretinal injection on Day 1 followed by triamcinolone acetonide as adjunct treatment by posterior sub-Tenon injection.

Drug: ASP2020

Part 2 Dose Expansion: Pediatric with macular dystrophies

EXPERIMENTAL

Pediatric participants will receive single optimal dose of ASP2020 established in part 1 by subretinal injection on Day 1 followed by triamcinolone acetonide as adjunct treatment by posterior sub-Tenon injection.

Drug: ASP2020

Interventions

Subretinal Injection

Part 1 Dose Escalation: Adolescent - High DosePart 1 Dose Escalation: Adolescent - Low DosePart 1 Dose Escalation: Adult - High DosePart 1 Dose Escalation: Adult - Low DosePart 2 Dose Expansion: Adult with macular dystrophiesPart 2 Dose Expansion: Pediatric with macular dystrophies

Eligibility Criteria

Age6 Years+
Sexall
Healthy VolunteersNo
Age GroupsChild (0-17), Adult (18-64), Older Adult (65+)

You may qualify if:

  • Documented clinical diagnosis of macular dystrophy with a STGD-type clinical presentation and molecular confirmation, defined as either:
  • STGD: presence of biallelic (pathogenic or likely pathogenic) ABCA4 variants, or one definite disease-causing ABCA4 variant together with a typical phenotype consistent with STGD.
  • STGD-like macular dystrophy: presence of one or more pathogenic variants in a gene known to cause macular dystrophy, as appropriate for its expected inheritance mode.
  • Sufficiently clear ocular media and adequate pupillary dilation to allow for all imaging procedures.
  • Intraocular pressure (IOP) of ≤ 21 mmHg
  • Participant has a spherical equivalent refractive error between +8.00 D and -10.00 D.
  • BCVA ranging from 20/500 to 20/40 (equivalent to 15 to 70 ETDRS letters)
  • For participants in the \> 20/80 to ≤ 20/40 BCVA range (moderate visual impairment \[MVI\]): presence of a visible definite or probable residual ellipsoid zone (EZ) on SD-OCT, and a total retinal SD-OCT central subfield thickness ≥ 150 micrometers (µm)
  • For participants in the ≥ 20/500 to ≤ 20/80 BCVA range (severe visual impairment): Presence of a residual ONL within the macular optical coherence tomography (OCT) scan area and Evidence of RPE disease/damage by means of SD-OCT (hypertransmission defect) and/or FAF imaging (questionably decreased autofluorescence/definitely decreased autofluorescence).

You may not qualify if:

  • Participant has a known history of significant systemic disease that could impact ocular health or confound study assessments, based on medical history or prior clinical documentation.
  • Participant has an autoimmune condition that requires treatment with immunomodulatory therapy and/or biologics that cause immunosuppression.
  • Participant has known diagnosis of diabetes mellitus with a documented glycated hemoglobin (HbA1c) value ≥ 7% 3 months prior to screening and based on available medical records.
  • Participant has a history or evidence of severe cardiac disease, cardiovascular or cerebrovascular disease, including a history of stroke within 12 months prior to screening.
  • Participant has any complicating systemic disease or active malignancy.
  • Participant has a known history of any systemic or metabolic condition, or physical examination finding that may significantly affect ocular health or interfere with the interpretation of study assessments.
  • Participant has presence of another known or suspected molecular diagnosis of macular or retinal disease that could confound interpretation of study outcomes, indicate a second concomitant retinal condition, or suggest a different etiology for the macular disease.
  • Participant has macular atrophy due to any cause other than a genetically or clinically confirmed diagnosis of STGD or STGD-like macular dystrophy.
  • Participant has evidence or history of choroidal neovascularization.
  • Participant has diagnosis of any form of uncontrolled glaucoma (for high-tension glaucoma IOP \> 25 mmHg).
  • Participant has a history of steroid-induced IOP elevation or known steroid responder status.
  • Participant has and/or is receiving treatment for thyroid eye disease.
  • Participant has diabetic retinopathy in excess of mild nonproliferative diabetic retinopathy
  • Participant has any other disease(s) affecting the optic nerve.
  • Participant has a history of anterior or posterior uveitis and/or presence of intraocular inflammation (trace anterior chamber cell or flare), or history of idiopathic or autoimmune-associated uveitis in either eye.
  • +11 more criteria

Contact the study team to confirm eligibility.

Sponsors & Collaborators

MeSH Terms

Conditions

Stargardt DiseaseMacular Degeneration

Condition Hierarchy (Ancestors)

Eye Diseases, HereditaryEye DiseasesRetinal DegenerationRetinal DiseasesGenetic Diseases, InbornCongenital, Hereditary, and Neonatal Diseases and Abnormalities

Study Officials

  • Medical Lead

    Astellas Institute for Regenerative Medicine

    STUDY DIRECTOR

Central Study Contacts

Astellas Institute for Regenerative Medicine

CONTACT

Study Design

Study Type
interventional
Phase
phase 1
Allocation
RANDOMIZED
Masking
NONE
Purpose
TREATMENT
Intervention Model
SEQUENTIAL
Sponsor Type
INDUSTRY
Responsible Party
SPONSOR

Study Record Dates

First Submitted

July 15, 2026

First Posted

July 29, 2026

Study Start

July 31, 2026

Primary Completion (Estimated)

September 30, 2029

Study Completion (Estimated)

September 30, 2029

Last Updated

July 29, 2026

Record last verified: 2026-07

Data Sharing

IPD Sharing
Will not share

Access to anonymized individual participant level data will not be provided for this trial. Further details on Astellas' data sharing policy can be found at https://www.clinicaltrials.astellas.com/transparency/.