Safety and Efficacy of Corneal Collagen Cross-Linking in Eyes With Keratoconus

Inclusion Criteria:

Subjects must meet all of the following criteria in order to be enrolled in the trial:

1. Be at least 12 years of age, male or female, of any race;

2. Provide written informed consent and sign a HIPAA form. Subjects who are under the age
of 18 (or have not yet reached the age of majority per local regulations) will need to
sign an assent form as well as having a parent or legal guardian sign an informed
consent;

3. Willingness and ability to follow all instructions and comply with schedule for
follow-up visits, including the ability to read English to complete the NEI-VFQ 25
questionnaire;

4. For females capable of becoming pregnant, agree to have urine pregnancy testing
performed at Visit 2 prior to randomization of the study eye and prior to treatment of
a fellow and/or cross-over eye; must not be lactating, and must agree to use a
medically acceptable form of birth control for at least one week prior to Visit 2, one
week prior to treatment of a fellow eye or cross-over eye, and continue to use the
method for one month following the last treatment. Acceptable forms for birth control
are spermicide with barrier, oral contraceptive, injectable or implantable method of
contraception, transdermal contraceptive, intrauterine device, or surgical
sterilization of partner. For non-sexually active females, abstinence will be
considered an acceptable form of birth control. Women considered capable of becoming
pregnant include all females who have experienced menarche and have not experienced
menopause (as defined by amenorrhea for greater than 12 consecutive months) or have
not undergone successful surgical sterilization (e.g. hysterectomy, bilateral tubal
ligation, or bilateral oophorectomy);

5. Subjects > 25 years old at the time of screening of their study eye must meet the
following criteria. Subjects ≤ 25 years old and all subjects who have their fellow-eye
or crossover eye treated are not required to meet these criteria;

- Having a diagnosis of progressive keratoconus defined as one or more of the
following changes over a period of 36 months or less:

1. An increase of ≥ 1.00 D in the steepest keratometry value (ksteep)

2. An increase of ≥ 1.00 D in regular astigmatism evaluated by subjective manifest
refraction or as evaluated by comparing eyeglass or contact lens prescriptions to
current subjective manifest refraction

3. A myopic shift (decrease in the spherical equivalent) of ≥ 0.50 D in subjective
manifest refraction or as evaluated by comparing eyeglass or contact lens
prescriptions to current subjective manifest refraction

4. A decrease ≥ 0.1 mm in the BOZR (Back Optical Zone Radius) in rigid contact lens
wearers where other information is not available

6. Having topographic evidence of keratoconus with a diagnosis of mild, moderate, or
severe keratoconus defined as the following:

- Mild Keratoconus:

1. Axial topography consistent with keratoconus

2. Flat Pentacam keratometry reading ≤ 51.00D

- Moderate Keratoconus:

1. Axial topography consistent with keratoconus

2. Flat Pentacam keratometry reading > 51.00 D and ≤ 56.00 D or astigmatism ≥
8.00 D

- Severe Keratoconus:

1. Axial topography consistent with keratoconus with marked areas of steepening

2. Flat Pentacam keratometry reading > 56.00 D

7. Presence of central or inferior steepening on the Pentacam map;

8. Have a maximum corneal curvature, as measured by Kmax, of ≥ 47.00 D;

9. BSCVA of ≥ 1 letter and ≤ 80 letters on ETDRS chart;

10. Contact Lens Wearers Only: Removal of contact lenses is required for a 1 week period
prior to the first screening refraction visit (and each subsequent Visit 1, as
necessary) and must remain out until the 1 month visit is completed;

11. Contact Lens Wearers Only: Manifest refraction must be stable between two consecutive
visits which occur at least 7 days apart. A stable refraction is one in which the
manifest refraction spherical equivalent and the average K (Km) on the Pentacam taken
at the first visit do not differ by more than 0.75 D from the respective measurements
taken at the second exam. A contact lens wearer is defined as someone who has worn
contact lenses in the eye to be treated in the last 30 days.

Exclusion Criteria:

Subjects must not meet any of the following criteria to be enrolled in the trial:

1. Contraindications, sensitivity or known allergy to the use of the test article(s) or
their components;

2. If female, be pregnant, nursing or planning a pregnancy during the course of the study
or have a positive urine pregnancy test at Visit 2 prior to randomization or treatment
of either eye;

3. Eyes classified as either normal, atypical normal, or keratoconus suspect on the
severity grading scheme;

4. A history of previous corneal surgery or the insertion of Intacs in the eye to be
treated;

5. A history of previous Limbal Relaxing Incision (LRI) procedure in the eye to be
treated;

6. Corneal pachymetry that is < 375 microns prior to epithelial debridement at the
thinnest point measured by Pentacam in the eye to be treated;

7. Eyes which are aphakic;

8. Eyes which are pseudophakic and do not have a UV blocking lens implanted;

9. Previous ocular condition (other than refractive error) in the eye to be treated that
may predispose the eye for future complications. For example:

1. History or evidence of active or inactive corneal disease (e.g., herpes simplex
keratitis, herpes zoster keratitis, corneal melt, recurrent corneal erosion
syndrome, corneal dystrophy, etc.);

2. Clinically significant corneal scarring in the cross-linking treatment zone that
is not related to keratoconus or, in the investigator's opinion, will interfere
with the cross-linking procedure;

10. A history of delayed epithelial healing in the eye to be treated;

11. Subjects with nystagmus or any other condition that would prevent a steady gaze during
the treatment or other diagnostic tests;

12. Subjects with a current condition that, in the investigator's opinion, would interfere
with or prolong epithelial healing;

13. Taking supplements containing Vitamin C (ascorbic acid) within 1 week of the
cross-linking treatment;

14. A history of previous corneal crosslinking treatment in the eye to be treated;

15. The subject should not have participated in any investigational drug or device study
within 30 days of screening or be concurrently enrolled in another investigational
drug or device study.

16. The Investigator may exclude or discontinue any subject for any sound medical reason.