Microwave Treatment and Corneal Collagen Crosslinking for Keratoconus

The objective of this study is to compare the safety and efficacy of the Vedera KXS (a
microwave-based procedure) combined with corneal collagen cross-linking performed with VibeX
(Riboflavin Ophthalmic Solution)and the KXL System to corneal collagen cross-linking alone in
reducing corneal curvature in patients with keratoconus. Patients will be randomized into one
of two treatment groups: Vedera KXS combined with corneal collagen cross-linking or collagen
cross-linking alone. The Vedera KXS procedure performs a controlled application of microwave
energy in an annular configuration. The goal of this procedure is to reshape the cornea to
flatten the cornea and improve corneal topography in patients with keratoconus. The primary
goal of collagen crosslinking is to stabilize the corneal shape in keratoconus and prevent
progression of the disease. Moreover, investigations of crosslinking have shown the procedure
not only to decrease keratoconus progression, but also to decrease the steepness of the cone
and improve uncorrected and best corrected visual acuity in some cases. Since the mechanism
of improvement differs between the procedures, this study will compare the combined
microwave/crosslinking treatment to crosslinking alone.

Inclusion Criteria:

- Be at least 18 years of age

- Provide written consent and sign a HIPAA form

- Willingness and ability to follow all instructions and comply with schedule for
follow-up visits

- For females capable of becoming pregnant, agree to have urine pregnancy testing
performed prior to treatment; must not be lactating, and must agree to use a medically
acceptable form of birth control for at least one week prior to the treatment and
continue to use the method until 1 month after the last dose of investigational
product.

- Having topographic evidence of keratoconus which is graded as moderate or severe
keratoconus

- Presence of central or inferior steepening on the Pentacam map

- Steepest keratometry (Kmax) value greater than or equal to 51.00D

- BSCVA of 80 letters or fewer for keratoconus on ETDRS chart

- Contact lens wearers only: remove contact lenses one week prior to the screening
refraction

- Contact lens wearers only: manifest refraction must be stable between two visits that
occur at least 7 days apart.

Exclusion Criteria:

- Contraindications, sensitivity or known allergy to the use of the test articles(S) or
their components

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

- Eyes classified as either normal,atypical normal,keratoconus suspect or mild
keratoconus on the severity grading scheme

- A history of the insertion of INTACS in the eye to be treated

- A history of previous limbal relaxing incision procedure in the eye to be treated

- Corneal pachymetry that is <350 microns at the thinnest point measured by Pentacam in
the eye to be treated

- Eyes which are aphakic

- Eyes which are pseudophakic and do not have a UV blocking lens implanted

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

- A history of delayed epithelial healing in the eye to be treated

- Patients with nystagmus or any other condition that would prevent a steady gaze during
the treatment or other diagnostic tests

- Patients with a current condition that, in the investigator's opinion,would interfere
with or prolong epithelial healing

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

- A history of previous corneal cross-linking treatment in the eye to be treated

- Have used an investigational drug or device within 30 days of the study or be
concurrently enrolled in another investigational drug or device study within 30 days
of the study