Corneal Crosslinking in Patients With Keratoconus and Post-Refractive Ectasia

The primary objective of this study is to evaluate two riboflavin-dosing regimens for corneal
collagen cross-linking to slow the progressive changes in corneal curvature in eyes with
progressive keratoconus or post-refractive ectasia.

Inclusion Criteria:

1. 10 years of age or older

2. Having documented ectasia on topography or tomography after previous refractive
surgery OR progressive keratoconus defined as one or more of the following changes
over a period of 36 months or less before randomization:

1. An increase of ≥ 1.00 D in the steepest keratometry value (or sim K)

2. An increase of ≥ 1.00 D in regular astigmatism evaluated by subjective manifest
refraction

3. A myopic shift (decrease in the spherical equivalent) of ≥ 0.50 D on subjective
manifest refraction

4. Documented decrease in visual acuity associated with irregular astigmatism and
topographic features of ectasia.

3. Subjects with keratoconus diagnosis only:

a. Axial topography consistent with keratoconus b. Presence of central or inferior
steepening on the Pentacam map. c. Presence of one or more slit lamp findings
associated with keratoconus, such as: i. Fleischer ring ii. Vogt striae iii. Corneal
thinning iv. Corneal scarring

4. Contact Lens Wearers Only: Removal of contact lenses for the required period of time
prior to the screening refraction:

Contact Lens Type Minimum Discontinuation Time Soft 3 Days Soft Extended Wear 1 Week
Soft Toric 2 Weeks Rigid gas permeable 2 Weeks

5. Signed written informed consent

Exclusion Criteria:

- 1. Any keratoconus patient over 21 years of age without evidence of progression of his
corneal deformity.

2. Patients with excessively thin corneas. 3. Previous ocular condition in the eyes to
be treated that may predispose the eye for future complications, for example:

a. History of corneal disease (e.g., herpes simplex, herpes zoster keratitis,
recurrent erosion syndrome, corneal melt, corneal dystrophy, etc.) b. Clinically
significant corneal scarring in the proposed treatment zone 4. A history of chemical
injury or delayed epithelial healing in the eye(s) to be treated.

5. A known sensitivity to treatment medications. 6. Patients with a current condition
that, in the treating physician's opinion, would interfere with or prolong epithelial
healing.

7. Pregnancy (including plan to become pregnant) or lactation during the course of the
study