Participate in Research at CU Anschutz

Adult

1. Are 18 years of age or older. 2. Provide written informed consent and Health Insurance Portability and Accountability Act (HIPAA) authorization prior to any study-related procedures (except the HIPAA requirement does not apply in Latin American countries). 3. Have a medically documented PCED of at least 7 days duration prior to Screening, that is refractory to one or more non-surgical treatments (eg, preservative free artificial tears, therapeutic contact lenses). 4. Be willing and able, during the 7-day washout period between the Screening and Day 1/Baseline visits, to self-administer in the Study Eye: preservative-free moxifloxacin ophthalmic solution 0.5% (eg, Vigamox) up to 3 times per day (TID), and preservative-free artificial tears (Refresh Classic) up to 4 times per day (QID) as needed. NOTE: the participant must also be willing to continue self-administering these treatments throughout the Treatment Period, along with their randomized study drug; if Investigator's standard of care (SoC) dosing regimen for moxifloxacin differs from the protocol (e.g., more than 3 times per day), the Sponsor and Medical Monitor will consider use of Investigator's SoC during the study. 5. The PCED is measured during slit-lamp examination at Screening and Day 1/Baseline, as follows: a. minimum of 0.2 mm of any linear measurement b. maximum of 8 mm of any linear measurement 6. If bilateral PCEDs are present at Screening or Day 1/Baseline, the participant is eligible, provided: a. the PCED is not larger than 8 mm maximum linear measurement in either eye. b. both eyes do not have central corneal involvement impacting the visual axis 7. Female participants must be one of the following: a) postmenopausal (defined as no menses for 1 year), b) surgically sterilized or partner is surgically sterilized, c) practicing abstinence as a lifestyle choice (not as a form of contraception), or d) consistently and correctly using protocol-specified birth control for the duration of the study (eg, a hormonal contraceptive, intrauterine device, diaphragm with spermicide, or condom with spermicide; see Appendix 4). Female participants who are neither postmenopausal nor surgically sterile require a negative urine pregnancy test at the Screening and Day 1/Baseline visits. 8. Have the ability and willingness to comply with study procedures.