NGF Treatment for Patients With Neuropathic Corneal Pain

This prospective, single center, interventional, open-label, single arm, non-randomized trial seeks to investigate the efficacy of Oxervate® (cenergermin 0.002% eye drops) on ameliorating the signs and symptoms of neuropathic corneal pain (NCP). The study aims to enroll 28 subjects with NCP. All patients will be evaluated for clinical symptoms and signs of NCP, corneal staining and nerve regeneration (by IVCM) at Baseline (Visit 2) through the end of study (16 weeks post treatment).

During the screening (Visit 1 / Day -8) all procedures for inclusion will be performed. From the day of screening the participants will stop any kind of further previous ocular treatment regime, except commercially available preservative free artificial tears provided by Sponsor for 7 days and 9 days as maximum (day -8 to day -1+2) until the baseline(Visit 2) . At the end of the washout period (day -8 to day -1+2), participants meeting the entry criteria for this study will be assigned to receive the Oxervate® at 4times/daily dosing in both eyes for 4 weeks.

At Week 1, participants will be queried for adverse events. If the participant reports side effects while on 4times/daily dosing, subjects will be instructed to begin a modified dosing regimen: 4 times daily for 3 days, then 1 day off dosing. At Week 4, participants will be evaluated for clinically significant changes. If resolution of NCP or improvement is observed, Oxervate® will be discontinued. If there is partial/no-improvement, participants will be instructed to begin an increased dosing regimen of 6times/daily. If at any point during the intervention period ocular pain/irritation is worsened for a prolonged period, Oxervate® intervention will be discontinued.

During the 8 weeks of intervention, only the administration of Oxervate® is allowed. Nevertheless, if strictly needed, the participant can take preservative free artificial tears (provided by Sponsor). The use (n° drops/day) of preservative free artificial tears will be clearly documented in a participant's diary and in the CRF.

Eligibility Criteria:
Inclusion Criteria:

* Male or female aged ≥ 18 years
* Symptoms of neuropathic corneal pain at least 3 months, such as burning, stinging, light sensitivity, discomfort or pain.
* Positive ICVM findings
* If female with childbearing potential, have a negative pregnancy test
* Best corrected distance visual acuity, using corrective lenses if necessary, in the study eye of at least +1.0 Log MAR (Snellen \<20/200)
* Satisfying all Informed Consent requirements
* Ability and willingness to comply with study procedures
* Ability to speak and understand the English language sufficiently to understand the study, provide written consent, and allow completion of all study assessments

Exclusion Criteria:

* Evidence of any active ocular infection
* Evidence of any intraocular inflammation
* Evidence of any persistent epithelial defect/ulcer
* Evidence of any corneal scar/corneal edema
* Presence of any other ocular conditions that require topical medications
* History of severe systemic allergy or severe ocular allergy
* Inability to suspend topical medications during the duration of the study
* Inability to suspend oral medications for NCP.
* No changes in VAS score after topical 0.5% proparacaine hydrochloride (Alcaine, Alcon, Fort Worth, TX)
* History of any ocular surgery within three months before study Visit 1(day 0)
* Ocular surgery expected during the 16 weeks of the trial
* Use of refractive/therapeutic contact lenses during the study period
* Female patients that are pregnant/have a positive pregnancy test result/are breast-feeding/intend to become pregnant during the study treatment period
* Drug addiction/alcohol abuse within the last year
* Participation in another clinical trial