Retinitis Pigmentosa Stem Cell Trials Recruiting Now in the USA

Study Details

What are They Looking At?

The main goal is to check the safety of a single eye injection of jCell (famzeretcel) over 6 months.

They will also compare changes in visual function at 6 months between the treatment group and a sham (mock) control group.

Type of Cells Used: human retinal progenitor cells (RPCs)

These are early-stage cells related to the retina (the light-sensitive tissue at the back of the eye). They are not fully developed eye cells and are used in research because they can be placed into the eye for study.

Cell Source / Cell Markers / Cell Manufacturing

The study record does not provide:

• where the cells come from
• whether they are from the patient or a donor

Dosage

Each treated participant receives a single injection containing 8.8 million retinal progenitor cells.

Delivery Method

• The treatment is delivered as a one-time intravitreal injection into the study eye.
• Intravitreal means the injection goes into the gel inside the eye.

Control Group (Sham)

Some participants receive a mock (sham) procedure in the study eye:

• the hub of a syringe (with no needle) is pressed against the eye to mimic an injection
• participants go through the same preparation as the treatment group, including anesthetics

Study Design

• This is a randomized, parallel-assignment Phase 2 trial.
• It is double-masked (the participant and the outcomes assessor are masked).
• Because of safety checks and the sham procedure, not all study staff can be masked.

What They’re Measuring

Time frame for measurements: 6 months

Primary Goal (Main Safety Measure)

Safety of the intravitreal injection of 8.8M jCell, assessed by:

• treatment-emergent adverse events (side effects that happen after treatment)
• immunogenicity (whether the body shows signs of an immune reaction)
• safety visual assessments (eye safety checks)

Secondary Measures (Vision and Quality-of-Life Measures)

They will also measure:

Best corrected visual acuity (BCVA) responder rate:

• improvement of at least 15 ETDRS letters
• improvement of at least 10 ETDRS letters

Peak contrast sensitivity (CS) responder rate:

• improvement of at least 0.3 log CS

• Mean change in BCVA
• Mean change in peak contrast sensitivity
• Mean change in central island visual field area
  (the central part of the visual field that is connected to where you are looking)

VA LV VFQ-48:

• mobility domain score change
• overall visual ability score change
  (patient questionnaire results reported as “logits” in the study record)

EQ-5D-5L:

• health status index score change
• EQ VAS score change (0 to 100 scale)

Next Steps

Follow-up Schedule

• Participants are followed and tested for 6 months after the procedure.
• The study record does not describe longer follow-up beyond this.

Study Details

What Are They Looking At?

The main goal of this study is to evaluate:

• Safety and tolerability of OpCT-001 after subretinal injection
• Early effects on:
• Visual function
• Functional vision
• Retinal structure
• Anatomical signs that the cells may survive in the retina

This is a first-in-human study, meaning this treatment has not been tested in people before.

Type of Cells Used

Photoreceptor precursor cells

These are immature cells related to photoreceptors (the light-sensing cells of the retina).

They are not fully developed rods or cones.

Cell Source / Cell Markers / Cell Manufacturing

Cell source:

• Cells are derived from human induced pluripotent stem cells (iPSCs)

Donor vs patient:

• The cells are not taken from the patient
• They are donor-derived (allogeneic)

Manufacturing details:

The study record does not describe:

• Reprogramming method
• Differentiation protocol
• Purity thresholds
• Release criteria

Dosage

Multiple dose levels are being tested:

• Up to 4 different dose levels in Phase 1
• 2 selected dose levels in Phase 2

Exact cell numbers per dose are not disclosed in the study record

Delivery Method

Subretinal injection into the study eye

Subretinal means:

• The cells are surgically injected underneath the retina
• This requires retinal surgery

Study Design

• Phase 1/2a interventional study
• Sequential assignment

Phase 1:

• Open-label
• Dose-escalation using a standard 3+3 design

Phase 2:

• Participants randomized 1:1 between two dose levels
• Surgical team unmasked
• Other study staff masked to dose assignment

What They’re Measuring

Time Frame for Measurements

Up to 52 weeks after treatment

Primary Goal (Main Safety Measure)

Safety is assessed by:

• Incidence of ocular treatment-emergent adverse events
• Incidence of non-ocular treatment-emergent adverse events

Measured from treatment through Week 52.

Secondary Measures (Structural Retinal Measures)

They will also measure:

• Change in outer retinal layer thickness
• Measured using spectral-domain optical coherence tomography (SD-OCT)
• Focused on the treated area of the retina in the study eye

Next Steps

Follow-up Schedule

• Participants are followed for at least 52 weeks after treatment
• The study record does not describe follow-up beyond this period

Study Details

What Are They Looking At?

The main goal of this study is to evaluate:

• Safety of DSP-3077 after surgery
• Tolerability (how well people handle the treatment)

The study will also explore:

• Whether the transplanted retinal tissue survives in the eye (engraftment)
• Any early signs of potential benefit
• Performance of the surgical delivery device

This is an early-phase study, meaning it is focused on safety, not proof of vision improvement.

Type of Cells Used

• Retinal sheets derived from induced pluripotent stem cells (iPSCs)

These are structured sheets of retinal tissue, not loose injected cells.

Cell Source / Cell Markers / Cell Manufacturing

Cell source

• Cells are derived from induced pluripotent stem cells (iPSCs)

Donor vs patient

• The cells are donor-derived (allogeneic)
• They are not taken from the patient’s own body

Cell markers

The study record does not list:

• Specific retinal cell markers
• Surface markers
• Maturation markers

Manufacturing details

The study record does not describe:

• Reprogramming method
• Differentiation protocol
• Purity thresholds
• Release or quality-control criteria

Dosage

Two dose levels are being tested:

• Low dose: retinal sheet area ≥ 0.8 mm² and < 2.4 mm²
• High dose: retinal sheet area ≥ 2.4 mm² and < 6.4 mm²

Each participant receives one dose in one eye only.

Delivery Method

• Single subretinal injection in one eye

Subretinal means:

• The retinal sheet is surgically placed under the retina
• This requires retinal surgery

Study Design

• Phase 1/2a interventional study
• Open-label (no masking)
• Single-arm (no placebo or control group)
• Dose-escalation design

Participants are assigned to three cohorts based on vision level and dose:

• Cohort 1: low dose
• Cohort 2: high dose
• Cohort 3: high dose with better starting vision

What They’re Measuring

Time Frame for Measurements

• Up to 60 months (5 years) after treatment
• Additional long-term safety follow-up up to 15 years

Primary Goal (Main Safety Measures)

Safety is assessed by tracking:

• Eye-related adverse events
• Eye-related serious adverse events
• Adverse events leading to stopping treatment
• Any serious adverse events, including death

All safety outcomes are monitored over 60 months.

Next Steps

Follow-up Schedule

• Frequent visits during the first 2 weeks after surgery
• Monthly visits through Month 4
• Every 3 months through Month 24
• Every 6 months through Month 60
• Annual safety follow-up from Year 6 to Year 15

Study Details

What Are They Looking At?

The main goal of this study is to evaluate:

• Safety, including:
  • Infection
  • Inflammation
  • Increased eye pressure
  • Patient-reported complaints

The study will also evaluate:

• Changes in visual acuity (how sharp your vision is)
• Changes in visual field (how wide an area you can see)
• Retinal function measured by electroretinography (ERG), a test that measures how well the retina responds to light
• Retinal structure using optical coherence tomography (OCT), a scan that shows detailed images of the retina
• Quality of life related to vision

This is an early-phase interventional study, meaning it is primarily focused on safety rather than proving vision improvement.

Type of Cells Used

• Umbilical cord–derived mesenchymal stem cells (UC-MSCs)
• Cells are administered together with conditioned medium (CM)

The study aims to assess whether these cells and their secreted factors may help inhibit or slow vision loss, rather than replace retinal cells.

Cell Source / Cell Markers / Cell Manufacturing

Cell source

• Cells are derived from umbilical cord tissue

Donor vs patient

• The cells are donor-derived (allogeneic)
• They are not taken from the patient’s own body

Dosage

Two dose levels are being tested:

• Low dose:
  • 1.5 million UC-MSCs in 2 mL of conditioned medium
• High dose:
  • 5 million UC-MSCs in 2 mL of conditioned medium

Delivery Method

• Peribulbar injection

Peribulbar means:

• The cells are injected around the outside of the eye
• The injection is not inside the eye
• The injection is not under the retina
• No retinal surgery is involved

Study Design

• Phase listed in study record: Phase 2 and Phase 3
• Interventional study
• Randomized
• Parallel assignment
• Double-masked (participants and investigators)
• Two treatment arms
  • Low-dose UC-MSC + CM
  • High-dose UC-MSC + CM
• No placebo or untreated control group

What They’re Measuring

Time Frame for Measurements

• From 1 day after injection up to 6 months

Primary Goals (Safety Measures)

Safety is assessed by tracking:

• Incidence of adverse events
• Frequency of adverse events
• Eye infection
• Eye inflammation
• Eye pressure changes
• Patient complaints

Functional and Structural Eye Tests

Measured at multiple time points:

• How clear your vision is
• How wide an area you can see
• A doctor’s look at the back of the eye
• A test that checks how well the retina responds to light
• A scan that takes detailed pictures of the retina

Secondary Measures

• Vision-related quality of life (NEI VFQ-25 questionnaire)
• Pain evaluation at 6 months
• Evaluation of eye bump appearance at 6 months

Study Details

What Are They Looking At?

The main goal of this study is to evaluate:

• Safety, including:
  • Eye pressure changes
  • Inflammation inside the eye
  • Retinal findings on eye examination
  • Adverse events reported by participants

The study will also evaluate signals of efficacy, including:

• Whether you can see letters more clearly on an eye chart (how sharp your vision is)
• Whether you can see a wider area around you, not just straight ahead (side vision)
• Whether you can tell the difference between light and dark objects, especially in low light
• Whether the structure of the retina (the light-sensing layer at the back of the eye) looks healthier on eye scans
• Whether the retina and the nerves that carry vision to the brain are working better when tested with electrical signals

This is an early-phase interventional study, meaning it is primarily designed to assess safety, not to prove long-term vision improvement.

Type of Product Used

Bone marrow mesenchymal stem cell–derived small extracellular vesicles (BM-MSC-derived sEVs)

Key points:

• These are not live stem cells
• sEVs are cell-free particles released by stem cells
• The product is manufactured to GMP (Good Manufacturing Practice) standards
• The study is testing whether these vesicles may deliver supportive signals to retinal tissue without injecting whole stem cells.

Cell Source / Cell Manufacturing

Cell source

• Bone marrow–derived mesenchymal stem cells (BM-MSCs)

Product type

• Small extracellular vesicles (sEVs) derived from BM-MSCs

Manufacturing

• GMP-compliant production
• Ethical approval granted by the institutional review board at Siriraj Hospital

Dosage

• Single dose: 50 micrograms of BM-MSC-derived sEVs
• Single injection
• One eye only

No dose escalation or multiple dosing arms are included.

Delivery Method

Intravitreal injection

This means:

• The injection is delivered inside the eye, into the vitreous cavity
• The procedure is done under topical local anesthesia
• A fine needle is used

Study Design

• Phase 1 / Phase 2
• Interventional study
• Single-group assignment
• Open-label (no masking)
• One treatment arm only
• No placebo group
• No untreated control group
• All participants receive the same intervention.

What They’re Measuring

Time Frame for Measurements

• From treatment through 1 year of follow-up

Primary Goals (Safety Measures)

Safety is assessed by tracking:

• Whether anything bad or uncomfortable happens after the treatment
• Whether the pressure inside the eye goes up or down
• Whether the eye becomes irritated or swollen on the inside
• What the doctor sees when they look at the front of the eye with a special light
• Pictures of the back of the eye, where vision cells live
• How the person feels and what they notice, like pain, blur, or discomfort

Functional and Structural Eye Tests

Measured over the 1-year period:

• How clear the person can see when wearing their best glasses. (LogMAR scale)
• How well the person can see light and dark differences, especially in dim light. (Contrast sensitivity testing)
• How much the person can see to the sides, not just straight ahead. (Kinetic visual field testing in four quadrants)
• A detailed picture of the center of the retina. (OCT)
• A scan that shows how blood flows in the retina. (OCT angiography)
• How thick the nerve layer that carries vision signals is. (Retinal nerve fiber layer thickness)
• The shape and size of the optic nerve, which sends vision signals to the brain. (Optic disc and cup volume)
• The size of a small blood-free area in the center of the retina. (Foveal avascular zone measurement)
• Tests that check how well the retina and vision nerves respond to light, including: (Electrophysiology tests)
  • A test that measures how the retina responds to flashes of light (Electroretinography – ERG)
  • A test that measures signals traveling from the eye to the brain (Sweep visual evoked potential)
  • A test that checks responses from different small areas of the retina (Multifocal electroretinography – mfERG)