Overview
The trial evaluates the effect of corneal crosslinking as pre-treatment before corneal transplantation. The goal is to improve graft survival by reducing pathological vessels through pre-treatment.
Description
Multicenter, two armed, controlled, open randomised parallel-group study to evaluate the effect of corneal crosslinking as pre-treatment vs. no pre-treatment ahead of full-thickness penetrating corneal transplantation.
After screening of inclusion and exclusion criteria, eligible subjects will be included after obtaining informed consent. Randomisation will be performed at a 5:4 ratio.
At the baseline assessment, a slit lamp examination and photo documentation as well as LaserFlareCellMeter (if available), corneal tomography, and Slit lamp Adapted Optical Coherence Tomography (SL-OCT) measurements will be performed. In addition, visual acuity and a vision-related quality of life will be assessed.
In the intervention arm, the study intervention (CXL) will then be administered to reduce CoNV 10-8 weeks prior to corneal transplantation. Two weeks after CXL a control will be performed including AE documentation, slit lamp examination, SL-OCT, corneal tomography, visual acuity and photo documentation. The study intervention will be repeated once if insufficient (less than 50%) reduction of CoNV should be observed (4 weeks after first CXL at the earliest and 4 weeks prior to corneal transplantation at the latest). All subjects in the intervention arm will then be scheduled for corneal transplantation.
In the control arm, subjects will be directly scheduled for corneal transplantation. Corneal transplantation will be performed as standard full-thickness penetrating procedure, and the graft (7.75 mm in diameter) will be secured with 16-24 interrupted single or double running 10-0 nylon single sutures (decision by the surgeon).
Postoperatively, follow-up assessments will be performed at 3, 6, 12, 18, and 24 months for all subjects and every 6 months thereafter until the end of the trial. A slit lamp examination, AE and photo documentation as well as LaserFlareCellMeter (if available), corneal tomography, SL-OCT, and corneal endothelial cell count measurements will be performed. In addition, visual acuity and a vision-related quality of life will be assessed.
Eligibility
Inclusion Criteria:
- Pathologically prevascularized cornea with need for corneal transplantation
- Written informed consent by subject and/or witness/legal representative, prior to any study-related procedures
- Adult male and female subjects ≥ 18 years old
- ≥ 2 corneal quadrants covered by pathological corneal neovascularization
- Absence of other clinical contraindications to any part or product of the treatment plan
- A cooperative attitude to follow up the study procedures
Exclusion Criteria:
- < 2 corneal quadrants covered by pathological neovascularization
- Corneal stromal thickness below 400 μm
- Active or suspected intraocular inflammation
- Active corneal ulceration
- Compromised eyelid mobility and/or symblepharon
- Allergy, sensitivity or intolerance to riboflavin or UV
- Contraindications to the local or systemic antibiotics and/or corticosteroids foreseen by the protocol
- Contraindications to the surgical protocol
- Clinically significant or unstable concurrent disease or other medical condition affecting grafting procedure
- Rheumatic diseases
- Subjects unlikely to comply with the study protocol
- Participation in another clinical trial where an investigational drug was received less than 4 weeks prior to screening visit
- Positive for human immunodeficiency virus (HIV)
- Known abuse of alcohol, drugs, or medicinal products
- Evidence of any other medical conditions (such as psychiatric illness, physical examination, or laboratory findings) that may interfere with the planned treatment, affect the subject's compliance, or place the subject at high risk of complications related to the treatment
- Employees of the sponsor, or employees or relatives of the investigator.
- Pregnant women and nursing mothers as corneal transplantation in standard care is performed under general anesthesia
- Persons held in an institution by legal or official order