Assessment of the Safety and Efficacy of 0.1% RGN-259 Ophthalmic Solution for the Treatment of NK: SEER-2

NCT05555589 | Recruiting Phase 3 FDA Drug

• 1 other identifier: RGN-NK-302
• Study Type: interventional
• Target: 70
• Locations: 4 countries
• Sites: 36

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

Keywords

Neurotrophic Keratitis; NK

Outcome Measures

Primary Outcomes (1)

• Percentage of subjects achieving complete healing of PED at Day 29

  Percentage of subjects achieving complete healing of the Persistent Epithelial Defect (PED) at Day 29 determined by corneal fluorescein staining as measured by the Central Reading Center.

  Day 29

Secondary Outcomes (5)

• Percentage of subjects achieving complete healing of PED at Day 29

  Day 29

• Percentage change from baseline of lesion size

  Day 8, 15, 22, 29, 36, and 43

• NK stage by Mackie classification

  Day 8, 15, 22, 29, 36, and 43

• Visual Acuity determined by ETDRS

  Day 8, 15, 22, 29, 36, and 43

• Corneal sensitivity inside the lesion determined by Cochet Bonnet aesthesiometer (Unit: mm)

  Day 8, 15, 22, 29, 36, and 43

Other Outcomes (5)

• Frequency and severity of AEs

  Day 8, 15, 22, 29, 36, and 43

• Number of participants with abnormal vital signs

  Day 1, 8, 15, 22, 29, 36, and 43

• Intraocular Pressure (Unit: mmHg)

  Day 1, 8, 29 and 43

Study Arms (2)

0.1% RGN-259 Opthalmic Solution

EXPERIMENTAL

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

Drug: RGN-259

Placebo Ophthalmic Solution (Vehicle for RGN-259 Ophthalmic Solution)

PLACEBO COMPARATOR

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

Drug: Placebo

Interventions

RGN-259 DRUG

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

Also known as: Tβ4, Thymosin Beta 4, Timbetasin

0.1% RGN-259 Opthalmic Solution

Placebo DRUG

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

Also known as: Vehicle Control

Placebo Ophthalmic Solution (Vehicle for RGN-259 Ophthalmic Solution)

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Be male or female of any race, at least 18 years of age;
• Have provided written informed consent;
• Be able and willing to follow instructions, including participation in all study assessments and visits;
• 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;
• 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;
• Have evidence of decreased corneal sensitivity ≤40 mm using the Cochet-Bonnet aesthesiometer at Visit 1;
• Have BCVA score ≤75 letter counts in the study eye based on the ETDRS protocol;
• Have at least one eye (the same eye) satisfy all criteria for d, e, f, g above;
• 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;
• Male subjects must agree to use an adequate method of contraception.

You may not qualify if:

• 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.
• Have any clinically significant slit-lamp findings in the study eye that in the opinion of the Investigator may interfere with the study parameters;
• 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;
• Have a Unanesthetized Schirmer's test score of ≤3 mm at Visit 1;
• Have a lid function abnormality (ex. Lagophthalmos) which, in the opinion of the Investigator, is the primary cause of the persistent epithelial defect;
• Have an ongoing ocular infection (bacterial, viral or fungal) or active inflammation (e.g., follicular conjunctivitis) in the study eye.
• History of any ocular surgery (including laser or refractive surgical procedures) within the three months before study enrollment.
• 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.
• Have any planned ocular surgical procedures or are likely to require ocular surgery for the study eye during the study;
• Have received Botox® injection to induce blepharoptosis in the study eye within 90 days prior to Visit 1;
• 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.
• Have used OxervateTM in the study eye within the past 2 months;
• Anticipate use of serum tears in the study eye during the study period.
• 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;
• 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;

Sponsors & Collaborators

• ReGenTree, LLC: lead

Study Sites (36)

Harvard Eye Associates

Laguna Hills, California, 92653, United States

RECRUITING

Loma Linda University Eye Institute

Loma Linda, California, 92354, United States

RECRUITING

Retina Consultants of Southern Colorado

Colorado Springs, Colorado, 80909, United States

ACTIVE NOT RECRUITING

Advance Vision Research Institute

Longmont, Colorado, 80503, United States

RECRUITING

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

Danbury, Connecticut, 06810, United States

RECRUITING

Nature Coast Clinical Research

Crystal River, Florida, 34429, United States

RECRUITING

University of Miami - Bascom Palmer Eye Institute, Miami

Miami, Florida, 33136, United States

RECRUITING

University of South Florida, Ophthalmolgoy

Tampa, Florida, 33612, United States

RECRUITING

Thomas Eye Group, P.C.

Sandy Springs, Georgia, 30328, United States

RECRUITING

Northwestern

Chicago, Illinois, 60611, United States

RECRUITING

Midwest Cornea Associates, LLC.

Carmel, Indiana, 46290, United States

RECRUITING

Huffman & Huffman, PSC

Lexington, Kentucky, 40509, United States

ACTIVE NOT RECRUITING

Midwest Vision Research Foundation

Chesterfield, Missouri, 63017, United States

RECRUITING

Washington University Eye Center

St Louis, Missouri, 63108, United States

RECRUITING

Metropolitan Eye Research and Surgery Institute

Palisades Park, New Jersey, 07650, United States

RECRUITING

Montefiore Medical Center

The Bronx, New York, 10467, United States

RECRUITING

Duke Eye Center

Durham, North Carolina, 27710, United States

RECRUITING

Oculus Research

Raleigh, North Carolina, 27617, United States

ACTIVE NOT RECRUITING

CORE, Inc. / Vita Eye Clinic

Shelby, North Carolina, 28150, United States

ACTIVE NOT RECRUITING

University Hospitals Cleveland Medical Center

Cleveland, Ohio, 44106, United States

RECRUITING

Cleveland Clinic, Cole Eye Institute

Cleveland, Ohio, 44195, United States

RECRUITING

Pacific ClearVision Institute

Eugene, Oregon, 97401, United States

ACTIVE NOT RECRUITING

Cataract & Laser Institute of Southern Oregon

Medford, Oregon, 97504, United States

RECRUITING

OHSU Casey Eye Institute

Portland, Oregon, 97239, United States

RECRUITING

UPMC Eye Center

Pittsburgh, Pennsylvania, 15213, United States

RECRUITING

MCOA Eye Care

San Antonio, Texas, 78240, United States

RECRUITING

Berkeley Eye Center

Sugar Land, Texas, 77478, United States

RECRUITING

Virginia Eye Consultants

Norfolk, Virginia, 23502, United States

RECRUITING

University of Washington, Department of Ophthalmology

Seatle, Washington, 98104, United States

RECRUITING

Università di Brescia

Brescia, Brescia, 25123, Italy

RECRUITING

Azienda Ospedaliero Universitaria Careggi

Florence, Firenze, 50134, Italy

RECRUITING

Gabinet Okulistyczny Prof Edward Wylegala

Katowice, Silesian Voivodeship, 40-594, Poland

RECRUITING

IMO Barcelona, Grupo Miranza

Barcelona, Barcelona, 08035, Spain

RECRUITING

Hospital La Arruzafa

Córdoba, Córdoba, 14012, Spain

RECRUITING

Instituto Oftalmológico Fernández-Vega

Oviedo, Principality of Asturias, 33012, Spain

RECRUITING

Aiken Prevención & Cirugía Ocular

Valencia, Valencia, 46004, Spain

RECRUITING

MeSH Terms

Interventions

thymosin beta(4)

Central Study Contacts

ReGenTree, LLC

CONTACT

609-734-4328; seer2info@regentreellc.com

Study Design

• Study Type: interventional
• Phase: phase 3
• Allocation: RANDOMIZED
• Masking: QUADRUPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: September 15, 2022
• First Posted: September 27, 2022
• Study Start: April 11, 2023
• Primary Completion: April 30, 2026
• Study Completion (Estimated): May 30, 2026
• Last Updated: December 23, 2025

Record last verified: 2025-12

Data Sharing

• IPD Sharing: Will not share

Locations

ES (4); IT (2); PL (1); US (29)