Thymosin Beta 4 (Tβ4) is a synthetic copy of the naturally-occurring 43-amino acid peptide that is found in a variety of tissues. Tβ4 promotes/accelerates wound repair in dermal, ocular, and cardiac animal models. Two recent pre-clinical evaluations have demonstrated that Tβ4 promotes corneal ocular surface defects healing in animal models of dry eye. RGN-259 (formulation of Tβ4 ophthalmic solution) mechanism of action offers potential to be a product that meets a major unmet medical need in patients with dry eye.
Tβ4 promotes wound repair and regeneration in various tissues. In the eye, it promotes corneal epithelial cell migration, decreases inflammation and has anti-apoptotic activities. It up-regulates the gene expression of laminin-5, a major subepithelial adhesion protein, located in the basement membrane region of the cornea, conjunctiva, and important in wound healing. In compassionate-use cases, Tβ4 has demonstrated efficacy in repairing non-healing neurotrophic corneal ulcers and other corneal epithelial wounds. In twenty-four nonclinical toxicology and safety pharmacology studies, the safety of Tβ4 has been demonstrated for its current and planned uses in man. The results of the two recent dry eye murine mouse model studies show that Tβ4 reduced corneal staining more than positive controls and demonstrated statistically significant reduction in staining compared to vehicle control. The results of these studies, in addition to data from compassionate use studies in patients with non-healing corneal surface defects, suggests that Tβ4 has a significant potential to be an important new safe and effective therapeutic in the treatment of dry eye syndrome.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
TREATMENT
Masking
QUADRUPLE
Enrollment
72
A preservative-free, sterile eye drop solution containing 0.1% (w/w) Tβ4 for direct instillation into each eye, twice a day (BID) for 28 days.
A preservative-free, sterile eye drop solution containing 0.0% (w/w) Tβ4 for direct instillation into each eye, twice a day (BID) for 28 days.
Corneal Staining (Inferior Region) in the Worst Eye in the Controlled Adverse Environment (CAE) Model, Which is a Regulated Environmental Setting Aimed at Exacerbating the Signs and Symptoms of Dry Eye
This is a test that uses orange dye (fluorescein) and a blue light to detect ocular surface defects associated with dry eye. If the test result is normal, the dye remains in the tear film on the surface of the eye and does not adhere to the eye itself. The test is carried out throughout the study till end of treatment Day 29. However, the primary outcome measure itself is determined on Day 29. The scale used to determine the difference in corneal fluorescein staining between RGN-259 and placebo is the ORA scale: 0= no staining (no detectable ocular defect)to 4= confluent staining( severe ocular defect). Worst eye: In the case that both eyes were eligible for analysis, the worst eye was chosen as the eye with the greater increase of inferior corneal staining from Visit 1 to Visit 2. If both eyes were equal, the eye with greater ocular discomfort at Visit 2 was chosen as the worst eye. If both eyes were equal at Visit 2, then the right eye was chosen as the worst eye.
Time frame: Day 29 (end of treatment)
Ocular Discomfort in the Worst Eye in the Controlled Adverse Environment(CAE) Model, Which is a Regulated Environmental Setting Aimed at Exacerbating the Signs and Symptoms of Dry Eye.
Dry eye causes ocular discomfort, which is measured using a validated 4-point ORA Scale from the start of the dosing till the end of treatment (Day 29). 0 = no discomfort to 4 = constant discomfort. If the measurement is lower, then improvement of ocular discomfort can be inferred. The test is carried out throughout the study till end of treatment Day 29. However, the primary outcome measure itself is determined on Day 29. Worst eye: In the case that both eyes were eligible for analysis, the worst eye was chosen as the eye with the greater increase of inferior corneal staining from Visit 1 to Visit 2. If both eyes were equal, the eye with greater ocular discomfort at Visit 2 was chosen as the worst eye. If both eyes had were equal at Visit 2, then the right eye was chosen as the worst eye.
Time frame: Day 29 (end of treatment)
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.
Number of Adverse Events as a Measure of Safety and Tolerability
The Adverse events, which will be followed, are: impairment of visual acuity, an increase in intraocular pressure (IOP), and an increase in corneal sensitivity in both eyes.
Time frame: Throughout the study till Day 29