Functional Antigen Matching in Corneal Transplantation

Study Overview
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Brief Summary
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Penetrating keratoplasty is one of the most commonly performed transplantation surgeries. Graft rejection is a major complication. HLA compatibility has already been demonstrated an effective prophylaxis in several retrospective investigations. The purpose of the investigators randomized clinical trial is to demonstrate superiority of HLA matching in comparison to random graft assignment with respect to the endpoint 'time to first endothelial graft rejection' in penetrating keratoplasty. The investigators will perform DNA-based allele resolution typing.

Official Title
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Clinical Trial to Investigate Superiority of HLA Matching in Comparison to Random Graft Assignment With Respect to the Endpoint 'Time to First Endothelial Graft Rejection' in Penetrating Keratoplasty.

Conditions
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Corneal Diseases

Intervention / Treatment
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* Other: HLA Matching
* Procedure: Penetrating keratoplasty


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Predicted waiting time for a 4/6 match lower than 6 months. Exclusion Criteria: Minority Legal incapacity

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: HLA Matching<br>HLA matching is exerted by selecting the donor with least-most additional HLA alleles. We will predict the waiting time for such a donor in order to assess eligibility for the trial [8]. In addition, we will dynamically adopt the degree of matching that is aimed at depending on the predicted time interval and actual waiting time: the first donors not exerting more than 7 mismatches at the triplet-amino-acid-residue-level (HLAMatchmaker method [6]) is accepted if the patient is waiting less than half of his predicted waiting time. The next available donor exerting a 2/6 match (or better) is assigned thereafter. The next graft will be assigned, regardless of HLA matching after 6 months. | Other: HLA Matching<br>* HLA matching is exerted by selecting the donor with least-most additional HLA alleles. We will predict the waiting time for such a donor in order to assess eligibility for the trial [8]. In addition, we will dynamically adopt the degree of matching that is aimed at depending on the predicted time interval and actual waiting time: the first donors not exerting more than 7 mismatches at the triplet-amino-acid-residue-level (HLAMatchmaker method [6]) is accepted if the patient is waiting less than half of his predicted waiting time. The next available donor exerting a 2/6 match (or better) is assigned thereafter. The next graft will be assigned, regardless of HLA matching after 6 months.<br>Procedure: Penetrating keratoplasty<br>* Corneal transplantation.<br>|
| Placebo Comparator: Random graft assignment<br> | Procedure: Penetrating keratoplasty<br>* Corneal transplantation.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Time to first endothelial graft rejection. |  | Mostly within the first six months. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Penetrating keratoplasty, HLA matching, Corneal diseases that require penetrating keratoplasty