hRPC for Retinitis Pigmentosa

(hRPCRP Trial)

Not currently recruiting at 4 trial locations

Overseen By Vince Holmes

Age: 18+

Sex: Any

Trial Phase: Phase 1 & 2

Sponsor: ReNeuron Limited

Must not be taking: Immunosuppressive agents

Disqualifiers: Ocular disease, Retinal detachment, High myopia, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: 1

Duration: 1 day

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial tests a new cell therapy called hRPC, designed to assist individuals with retinitis pigmentosa, a condition that leads to vision loss. The primary goal is to determine if a single injection of these cells is safe and well-tolerated in those with significant vision impairment due to this condition. Suitable candidates have been diagnosed with retinitis pigmentosa and experience low vision in at least one eye. Researchers will monitor participants for two years to assess safety and any potential vision improvement. As a Phase 1/Phase 2 trial, this research aims to understand how the treatment works in people and measure its effectiveness in an initial, smaller group.

Will I have to stop taking my current medications?

The trial does not specify if you need to stop taking your current medications. However, you cannot participate if you have used systemic immunosuppressive agents (like corticosteroids) in the 6 months before treatment.

Is there any evidence suggesting that hRPC is likely to be safe for humans?

Research has shown that special cells called human retinal progenitor cells (hRPC) might help treat retinitis pigmentosa, a condition that leads to vision loss. In earlier studies, researchers safely injected these cells into the eye. One study confirmed the long-term safety of this treatment, suggesting it could help repair vision. Although this information is still early, it offers hope that hRPC could be a safe treatment for people with this condition. The current trial aims to further assess the safety of hRPC. Participants will receive one injection and be monitored for two years to ensure the treatment's safety. ^{1 2 3 4 5}

Why do researchers think this study treatment might be promising?

Unlike standard treatments for retinitis pigmentosa, which often focus on managing symptoms or slowing the disease's progress, the hRPC treatment uses human retinal progenitor cells. This approach is exciting because it aims to replace damaged retinal cells and potentially restore vision, rather than just slow down its loss. The delivery method is also unique, involving a direct subretinal injection, which allows the cells to integrate directly into the retina. Researchers are optimistic about this treatment because it represents a regenerative approach, offering hope for improved vision and quality of life.

What evidence suggests that hRPC might be an effective treatment for retinitis pigmentosa?

Research has shown that human retinal progenitor cells (hRPC) might improve vision in some individuals with retinitis pigmentosa. In this trial, participants will receive a single subretinal administration of hRPC. Studies have found that hRPC can enhance vision clarity in some patients, particularly with higher doses. Early results indicate that these cells are safe and might help repair vision loss over time. Although further research is necessary, the initial findings are promising for hRPC as a potential treatment option. ^{1 3 4 5 6}

Who Is on the Research Team?

Jason Comander, MD

Principal Investigator

Massachusetts Eye and Ear Infirmary (MEEI)

Vince Holmes

Principal Investigator

ReNeuron Limited

Are You a Good Fit for This Trial?

Inclusion Criteria

You are physically healthy enough to have a surgery called vitrectomy and receive an injection under your retina.

Have ability to give written informed consent as evidenced by signature on the subject consent form

Be able to complete the entire microperimetry test, and demonstrate adequate fixation and consistency between baseline readings such that the accuracy of both baseline and follow on testing should enable the detection of clinically significant changes in retinal sensitivity

Exclusion Criteria

High myopia (>6 diopters) in the study eye

You have an eye condition or problem that would make it difficult to accurately evaluate your eye during the study.

You have had a surgery called vitrectomy in the eye being studied.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants receive a single subretinal injection of hRPC cells in one eye

1 day

1 visit (in-person)

Follow-up

Participants are monitored for safety and tolerability, with detailed ophthalmic examinations and imaging

24 months

Regular visits (in-person)

What Are the Treatments Tested in This Trial?

Interventions

• hRPC

How Is the Trial Designed?

Group I: human retinal progenitor cells (hRPC) Experimental Treatment 1 Intervention

Single subretinal administration of human retinal progenitor cells (hRPC)

Who Is Running the Clinical Trial?

ReNeuron Limited

Lead Sponsor

Trials

8

Recruited

240+

Published Research Related to This Trial

The study successfully registered 1890 patients with retinitis pigmentosa in Denmark, achieving an overall completeness of about 80%, which improved significantly for more recent birth cohorts.

The majority of patients (73%) were diagnosed with high confidence, and the data collected is valuable for ongoing epidemiological, clinical, and genetic research into the disease.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

A population survey of retinitis pigmentosa and allied disorders in Denmark. Completeness of registration and quality of data. Haim, M., Holm, NV., Rosenberg, T.[2019]

Citations

1.

pubmed.ncbi.nlm.nih.gov

pubmed.ncbi.nlm.nih.gov/40927136/

Retinal progenitor cells (jCell) for retinitis pigmentosa

The exploratory efficacy data suggest potential improvement of BCVA in some RP patients, particularly at the highest dose. While viewed ...

2.

clinicaltrials.gov

clinicaltrials.gov/study/NCT03073733

NCT03073733 | Safety and Efficacy of Intravitreal Injection ...

This study evaluates the changes in visual function at 12 months following a single injection of human retinal progenitor cells compared to sham treated ...

3.

pmc.ncbi.nlm.nih.gov

pmc.ncbi.nlm.nih.gov/articles/PMC5622579/

Long-term safety of human retinal progenitor cell ...

Our study for the first time confirmed the long-term safety and feasibility of vision repair by stem cell therapy in patients blinded by retinitis pigmentosa.

4.

frontiersin.org

frontiersin.org/journals/cellular-neuroscience/articles/10.3389/fncel.2025.1646156/full

Retinal progenitor cells (jCell) for retinitis pigmentosa

While outcomes from this small safety study are preliminary, the data are suggestive of an improvement of visual acuity in some patients with this ...

5.

retinalphysician.com

retinalphysician.com/issues/2020/march/clinical-trial-download-phase-12a-data-on-human-retinal-progenitor-cell-therapy/

CLINICAL TRIAL DOWNLOAD: Phase 1/2a Data on ...

The study investigated Reneuron's human retinal progenitor cell (hRPC) cells for the treatment of retinitis pigmentosa.

6.

clinicaltrials.gov

clinicaltrials.gov/study/NCT02464436

Safety and Tolerability of hRPC in Retinitis Pigmentosa

hRPC is a cell therapy for retinitis pigmentosa. This is a first-in-human, dose escalation study in which participants with retinitis pigmentosa will ...