Recruiting
Phase 3

RGN-259

Sponsor:

ReGenTree, LLC

Code:

NCT05555589

Conditions

Neurotrophic Keratopathy

Eligibility Criteria

Sex: All

Age: 18+

Healthy Volunteers: Not accepted

Interventions

RGN-259

Placebo

Study Details

Brief summary:

The objective of this study is to compare the safety and efficacy of RGN-259 to placebo for the treatment of Neurotrophic Keratopathy (NK)

Conditions

Neurotrophic Keratopathy

Study ID

NCT05555589

Start date

Apr 11, 2023

Status verified date

Dec, 2025

Completion date

May 30, 2026

Anticipated

Primary completion date

Apr 30, 2026

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 18+

Healthy Volunteers: Not accepted

Inclusion Criteria

1. Be male or female of any race, at least 18 years of age;
2. Have provided written informed consent;
3. Be able and willing to follow instructions, including participation in all study assessments and visits;
4. At the time of Visit 1, have documentation or observation of a Persistent Epithelial Defect (PED) in one or both eyes, defined as a corneal epithelial defect that has not resolved after 1 week of conventional treatment using non-preserved ocular lubricants, non-preserved topical ophthalmic antibiotics, oral doxycycline, patching, amniotic membrane, serum tears, and/or therapeutic contact lenses;
5. Have stage 2 or 3 neurotrophic keratopathy (Mackie Classification) in at least one eye of which the longest dimension (length or width) of the defect measures a minimum length of 1 mm (study eye) and which is confirmed by the Investigator not to be simply superficial punctate keratitis, at Visit 1;
6. Have evidence of decreased corneal sensitivity ≤40 mm using the Cochet-Bonnet aesthesiometer at Visit 1;
7. Have BCVA score ≤75 letter counts in the study eye based on the ETDRS protocol;
8. Have at least one eye (the same eye) satisfy all criteria for d, e, f, g above;
9. Female subjects of child-bearing potential must be non-lactating and using and agree to continue using an acceptable method of contraception for at least 4 weeks prior to the first dose of study product and until 12 weeks after last dose, and have a negative urine pregnancy test during screening;
10. Male subjects must agree to use an adequate method of contraception.

Exclusion Criteria

1. Have any condition that, in the opinion of the Investigator, would interfere with the subject's ability to complete the study, would interfere with the interpretation of safety or efficacy, or would present an undue risk to the subject.
2. Have any clinically significant slit-lamp findings in the study eye that in the opinion of the Investigator may interfere with the study parameters;
3. Clinically significant active blepharitis, meibomian gland dysfunction (MGD), or lid margin inflammation, or active ocular allergy in study eye that requires treatment that in the opinion of the investigator may interfere with the study parameters;
4. Have a Unanesthetized Schirmer's test score of ≤3 mm at Visit 1;
5. Have a lid function abnormality (ex. Lagophthalmos) which, in the opinion of the Investigator, is the primary cause of the persistent epithelial defect;
6. Have an ongoing ocular infection (bacterial, viral or fungal) or active inflammation (e.g., follicular conjunctivitis) in the study eye.
7. History of any ocular surgery (including laser or refractive surgical procedures) within the three months before study enrollment.
8. Prior surgical procedure(s) for the treatment of NK (e.g., tarsorrhaphy, conjunctival flap, etc.) within the three months before study enrollment with the exception of amniotic membrane transplantation.
9. Have any planned ocular surgical procedures or are likely to require ocular surgery for the study eye during the study;
10. Have received Botox® injection to induce blepharoptosis in the study eye within 90 days prior to Visit 1;
11. Have used contact lenses (for therapeutic or refractive correction) in the study eye within 14 days prior to Visit 1, or anticipate use of contact lenses during the study period.
12. Have used OxervateTM in the study eye within the past 2 months;
13. Anticipate use of serum tears in the study eye during the study period.
14. Have a presence or history of any ocular or systemic disorder or condition that might hinder the efficacy of the study treatment or its evaluation, could possibly interfere with the interpretation of study results, or could be judged by the Investigator to be incompatible with the study visit schedule or conduct;
15. Have used drugs which affect lacrimation or function of the trigeminal nerve within 30 days of Visit 1 or anticipate use of these systemic medication throughout the course of the study;
16. Have any autoimmune or chronic inflammatory disease that might have hindered the efficacy of the study treatment or its evaluation;
17. Be on topical (Ocular/Nasal) immunosuppressive therapy within 30 days prior to screening or is likely to require this during the course of the study;
18. Have a known allergy and/or sensitivity to the study product or its components;
19. History of drug, medication or alcohol abuse or addiction;
20. Have participated in an investigational drug study within 30 days prior to screening;
21. Have fever, inflammation, or systemic signs of illness suggestive of systemic or invasive infection, including COVID-19 or a positive test for COVID-19, within 2 weeks prior to first dose of study drug.

Study Design

Enrollment

70 participants

Anticipated

Allocation

Randomized

Intervention Model

Parallel Assignment

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

experimental: 0.1% RGN-259 Opthalmic Solution

It is a preservative-free, sterile eye drop solution containing Tβ4 for direct instillation into study eye(s), five times per day for 28 days

placebo comparator: Placebo Ophthalmic Solution (Vehicle for RGN-259 Ophthalmic Solution)

It is composed of the same excipients as RGN-259 but does not contain Tβ4

Interventions

RGN-259

A preservative-free, sterile eye drop solution containing Tβ4 for direct instillation into study eye(s), five times per day for 28 days

Placebo

It is composed of the same excipients as RGN-259 but does not contain Tβ4. Direct instillation into study eye(s), five times per day for 28 days

Primary outcome measure

  • Percentage of subjects achieving complete healing of PED at Day 29 [ Time Frame: Day 29 ]

Central Contacts and Locations

Central contacts

Locations

Harvard Eye Associates

Recruiting

Laguna Hills, California, United States, 92653

Loma Linda University Eye Institute

Recruiting

Loma Linda, California, United States, 92354

Advance Vision Research Institute

Recruiting

Longmont, Colorado, United States, 80503

Connecticut Eye Consultants, P.C. Danbury Eye Physicians & Surgeons

Recruiting

Danbury, Connecticut, United States, 06810

Nature Coast Clinical Research

Recruiting

Crystal River, Florida, United States, 34429

University of Miami - Bascom Palmer Eye Institute, Miami

Recruiting

Miami, Florida, United States, 33136

University of South Florida, Ophthalmolgoy

Recruiting

Tampa, Florida, United States, 33612

Thomas Eye Group, P.C.

Recruiting

Sandy Springs, Georgia, United States, 30328

Northwestern

Recruiting

Chicago, Illinois, United States, 60611

Midwest Cornea Associates, LLC.

Recruiting

Carmel, Indiana, United States, 46290

Midwest Vision Research Foundation

Recruiting

Chesterfield, Missouri, United States, 63017

Washington University Eye Center

Recruiting

St Louis, Missouri, United States, 63108

Metropolitan Eye Research and Surgery Institute

Recruiting

Palisades Park, New Jersey, United States, 07650

Montefiore Medical Center

Recruiting

The Bronx, New York, United States, 10467

Duke Eye Center

Recruiting

Durham, North Carolina, United States, 27710

University Hospitals Cleveland Medical Center

Recruiting

Cleveland, Ohio, United States, 44106

Cleveland Clinic, Cole Eye Institute

Recruiting

Cleveland, Ohio, United States, 44195

Cataract & Laser Institute of Southern Oregon

Recruiting

Medford, Oregon, United States, 97504

OHSU Casey Eye Institute

Recruiting

Portland, Oregon, United States, 97239

UPMC Eye Center

Recruiting

Pittsburgh, Pennsylvania, United States, 15213

MCOA Eye Care

Recruiting

San Antonio, Texas, United States, 78240

Berkeley Eye Center

Recruiting

Sugar Land, Texas, United States, 77478

Virginia Eye Consultants

Recruiting

Norfolk, Virginia, United States, 23502

University of Washington, Department of Ophthalmology

Recruiting

Seatle, Washington, United States, 98104

More Information

Sponsor

ReGenTree, LLC

Last update posted

Dec 23, 2025

Last verified

Dec, 2025

Keywords

  • Neurotrophic Keratitis
  • NK

Trial information was received from ClinicalTrials.gov and was last updated on 2026-10-07. This information was provided to ClinicalTrials.gov by ReGenTree, LLC on 2025-12-23. Recruitment status is synced daily from ClinicalTrials.gov and may not reflect the sponsor's current status. Confirm during your call.