CSB-C20-003

This study will enroll subjects with stage 2 or 3 neurotrophic keratitis. Subjects will be randomized in a 1:1 ratio to the CSB-001 investigational treatment arm or vehicle control arm. All subjects will dose with the randomized treatment four times daily for 8 weeks (controlled treatment phase). During the controlled treatment phase, subjects will return to the clinic weekly from Day 0 to Week 8, and again at Week 10. Subjects randomized to the vehicle arm who are not healed will have the opportunity to participate in an open-label uncontrolled treatment phase.

Inclusion Criteria

• Subjects with stage 2 (PED) or stage 3 (corneal ulcer) NK. Subjects with bilateral NK may enroll in the study but only one eye will be selected as the study eye (worse eye) and be treated with test article. The non-study eye may not be treated with Oxervate concurrently.
•  Subjects with no clinical evidence of improvement in the PED or corneal ulcer within the 2 weeks prior to study enrollment despite the use of conventional non-surgical treatments for neurotrophic keratitis (e.g., preservative-free artificial tears, gels or ointments; discontinuation of preserved topical drops and medications that can decrease corneal sensitivity; therapeutic contact lenses [either silicone hydrogel or rigid gas permeable]) as determined by the investigator or referring physician's medical record.
• Subjects with clinical evidence of decreased corneal sensitivity within the area of the PED or corneal ulcer and outside of the area of the defect in at least one corneal quadrant in the study eye in the opinion of the investigator (assessed with a cotton wisp, or the Cochet-Bonnet aesthesiometer if available at the site).

Exclusion Criteria

• Any active ocular infection (bacterial, viral, fungal, or protozoal) or active ocular inflammation not related to NK in either eye in the opinion of the investigator. Infectious epithelial keratitis including herpetic keratitis (i.e., dendritic lesions or geographic ulcers) in either eye is excluded. Subjects on oral antibiotic at the time of screening are eligible but should continue the medication for the duration of the study.
•  Previous use of Oxervate in the study eye within the past 4 months.
• Any other ocular disease that will require topical ocular treatment in the study eye over the course of the study.

Study Requirements

20 week study in two phases. Phase 1 is 10 visits over 8-10 weeks; includes eye exams, vision testing, and imaging at every visit. Phase 2 is 9-10 visits over 8-10 weeks; includes eye exams, vision testing, and imaging at every visit.