This Study is a First In Human clinical investigation addressed to evaluate the safety and efficacy of a novel intra-corneal nitinol device (Investigational Medical Device: GROSSO® implant) for the treatment of advanced keratoconus disease of the eye.

The medical device under investigation is a sterile thin 8-mm diameter circular scaffold made of a nickel-titanium alloy (nitinol) that is intended as a permanent implant that is surgically inserted into the cornea in order to modify force by inducing a change in corneal shape and consequently improving vision. This study is aimed at adults with a stage 3- 4 keratoconus, a central K reading > 47.2 D and RMS of coma aberration > 2.5 μm, which are not recommended for Intrastromal Corneal Ring Segments (ICRS) and are recommended for keratoplasty. Therefore, this study represents a salvage route to preserve the cornea. Envisaged worst case scenario of failure of the experimental device patients would be redirected to keratoplasty.

Study aims to treat 12 patients separated by a safety period of at least 14 days between each one allowing safety monitoring. For each patient, the following treatment strategy will be applied:

• Unilateral KC: the affected eye meeting the eligibility criteria will be treated.
• Bilateral KC, one eye meeting the eligibility criteria: the eligible eye will be treated.
• Bilateral KC, both eyes meeting the eligibility criteria: the most severely compromised eye will be treated. Primary study objective is safety by identification or any local or systemic adverse events. Secondary objective will aim to evaluate efficacy that means a consequently improving of vision. Patients will be monitored at 1, 7, 21, 60, 180 and 365 days post implant surgery. Upon observance or any serious adverse event, increase in ocular pressure, device migration or discomfort, medical criteria or patient request, the patient will be offered for the device removed. The study will be early terminated if 3 patients have the experimental device removed for any reason or 4 patients withdraw from study.

Inclusion Criteria:

• Signed and dated informed consent form.
• Male and female ≥ 18 years old.
• Not recommended for ICRS.
• Recommended for keratoplasty.
• Minimum corneal thickness ≥ 350 μm.
• Best Distance Spectacle Corrected Visual Acuity (BDSCVA) with the ETDRS test ≥ 0.30 logMAR (<= 0,50 decimal notation).
• BCVA with RGP contact lens with the ETDRS test 10 letters or more than BCVA with spectacles.
• Have stable or stabilized disease for 12 months (in case of crosslinking, it must have been done at least 12 months prior to intervention).
• Have a KC stage 3-4 according to Investigator's judgement, with a central K readings > 47.2 D and RMS of coma aberration > 2.5 μm.
• Have no known or suspected allergy to nickel.
• Female subject of childbearing potential is eligible to participate if declaring she is not pregnant, or not breastfeeding and agree to use highly effective contraception (defined as method which results in a failure rate of <1% annually) and must abstain from egg donation or storage throughout the study period.

Exclusion Criteria:

• Inability of patient and/or relatives to understand the clinical investigation procedures and thus inability to give informed consent.
• Untreated progressive KC.
• Single functioning eye.
• Other ocular diseases (eyelids malposition, uveitis, ocular hypertension, glaucoma, cataract, retinal disorders) or corneal surgeries (refractive corneal surgery, keratoplasty), except corneal crosslinking.
• Systemic collagenopathies and/or vasculitis, and other diseases that in the opinion of the principal Investigator, may be contraindicated.
• Suspected or known intolerance or hypersensitivity to any of the treatments indicated in the CIP and/or to any component of the device (i.e. nickel).

De-identified individual participant data that underlie the results reported in this study will be made available upon reasonable request from qualified researchers, subject to the sponsor's discretion, in order to protect participant privacy and sponsor confidentiality.