Facilitation of Corneal Re-epithelialization After Photorefractive Keratectomy

Study Overview
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Brief Summary
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Photorefractive keratectomy (PRK) or surface ablation is one of the most commonly used surgical procedures to correct refractive errors, which was proved to be safe and effective. In PRK, the corneal epithelium is removed by various techniques such as diluted alcohol, manual debridement, brush, or excimer laser, before the refractive excimer laser ablation of the corneal stroma. Compared to laser in situ keratomileusis (LASIK), the two main drawbacks for PRK are slower visual recovery and discomfort in the immediate postoperative period, due to the epithelial removal. Corneal healing is a complex process involving cellular interaction and reaction with various molecules (proteases, growth factors, and epithelial and stromal cytokines). Enhanced corneal re-epithelialization may reduce the risk for corneal infection and stromal scarring or melting. Over the past few years, a new type of matrix therapy by ReGeneraTing Agent (RGTA) has provided encouraging results, accelerating the healing of chronic skin ulcers in diabetes or vascular origin. RGTAs mimic the action of heparin sulfate molecules, breaking the negative repair-destruction cycle occurring in chronic lesions and inhibit proteolytic enzymes in vitro. In the domain of ophthalmology, RGTA has been reported to show encouraging results in the treatment of corneal ulcer and dystrophies of various etiologies. The Cacicol20 is an RGTA that binds to matrix proteins to protect them from proteolysis; the extracellular matrix microenvironment protection improves the production of signals and growth factors needed for tissue healing. It is supplied as a sterile single-dose solution of alpha 1-6 poly-carboxymethyl glucose sulfate described and synthesized as in US Patent Number 6689741, with dextran T40 and 0.9% sodium chloride as excipients. It contains no component of animal or biological origin, and penetrates into the cornea without crossing Descemet´s membrane (no intraocular penetration). The Cacicol20 has been reported to be effective in treatment of neurotrophic ulcers and persistent epithelial defects which were unresponsive to the common treatment approaches. Therefore, we expect that the Cacicol20 may facilitate the corneal re-epithelialization after PRK.

Official Title
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Treatment of Postoperative Discomfort/Pain and Facilitation of Corneal Reepithelialization After Photorefractive Keratectomy

Conditions
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Corneal Erosion

Intervention / Treatment
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* Device: Cacicol20
* Device: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients undergoing bilateral PRK surgeries for treatment of refractive error Age over 18 years Refractive stability for at least 2 years Exclusion Criteria: Ocular pathology, including keratoconus or suspected keratoconus, glaucoma, and epithelial defects Previous corneal surgery Systemic disease that might affect corneal wound healing.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Cacicol20<br>One drop of Cacicol20 will be applied 4-6 hours after the surgery, in one of the randomly chosen eye, and thereafter one drop daily until the reepithelialization is completed. | Device: Cacicol20<br>* Cacicol20 is supplied as a sterile single-dose solution of alpha 1-6 poly-carboxymethyl glucose sulfate One drop is instilled at each application to impregnate cornea.<br>* Other names: regenerative medicine;|
| Placebo Comparator: Placebo<br>One drop of conservative free artificial tear (Oculac, Thea Laboratories) will be applied to one eye at the same time when Cacicol20 is instilled to the other eye. | Device: Placebo<br>* Ocluac is artificial tear which contains Hydroxypropylmethyl Cellulose and Sodium Chloride, It is presented in a 0.4 mL vial. One drop is delivered at each application.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Re-epithelialization time | The patients will be examined daily the changes of reepithelialization area, until the re-epithelialization is complete. The days that takes for complete reepithelialization will be recorded. | 5 days postoperatively | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Discomfort during reepithelialization | Patient´s subjective evaluation of ocular symptoms including pain, burning, stinging, tearing, and photophobia in the two eyes, with score ranging from 0-5 (0 representing absence of symptom and 5 representing unbearable symptom) will be performed daily | 5 days postoperatively |