Collaborative Corneal Transplantation Studies (CCTS)
|The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details.|
|ClinicalTrials.gov Identifier: NCT00000137|
Recruitment Status : Completed
First Posted : September 24, 1999
Last Update Posted : September 17, 2009
|First Submitted Date ICMJE||September 23, 1999|
|First Posted Date ICMJE||September 24, 1999|
|Last Update Posted Date||September 17, 2009|
|Study Start Date ICMJE||May 1986|
|Primary Completion Date||Not Provided|
|Current Primary Outcome Measures ICMJE||Not Provided|
|Original Primary Outcome Measures ICMJE||Not Provided|
|Change History||Complete list of historical versions of study NCT00000137 on ClinicalTrials.gov Archive Site|
|Current Secondary Outcome Measures ICMJE||Not Provided|
|Original Secondary Outcome Measures ICMJE||Not Provided|
|Current Other Outcome Measures ICMJE||Not Provided|
|Original Other Outcome Measures ICMJE||Not Provided|
|Brief Title ICMJE||Collaborative Corneal Transplantation Studies (CCTS)|
|Official Title ICMJE||Not Provided|
|Brief Summary||To determine whether histocompatibility matching of corneal transplant donors and recipients can reduce the incidence of graft rejection in high-risk patients.|
Approximately 20 percent of corneal transplant patients, about 6,000 per year, face donor tissue rejection at rates of up to 60 percent because of corneal vascularization or prior graft rejection. Histocompatibility antigen matching and/or crossmatching may have offered these patients an improved chance for successful outcome.
The Collaborative Corneal Transplantation Studies Group conducted two controlled, double-masked studies addressing distinct scientific questions about donor-recipient histocompatibility matching. The Crossmatch Study was a randomized study assessing the effectiveness of crossmatching in preventing graft rejection among high-risk patients with lymphocytotoxic antibodies. The Antigen Matching Study was a prospective, double-masked, observational study of the effectiveness of HLA-A, -B, and -DR donor-recipient matching in high-risk patients who had no lymphocytotoxic antibodies.
Six clinical centers recruited high-risk patients and collaborated with their local eye banking and organ procurement agencies in procuring donor corneal tissue. For each of the two studies, a total of 400 patients were sought. Blood samples from each enrolled patient were sent to the local CCTS tissue typing laboratory for HLA typing, and serum samples were sent to the Central Laboratory to be screened for preformed lymphocytotoxic antibodies. Depending on the results of the testing, patients were entered into the Crossmatch Study or the Antigen Matching Study.
As corneal donors became available, donor blood samples were HLA typed at the local laboratories and crossmatched against all CCTS patients who awaited transplantation. Results of the testing were entered in a national, 24-hour computerized allocation system operated by the United Network for Organ Sharing (UNOS). Patients in the Crossmatch Study received a cornea from either a positively crossmatched donor or a negatively crossmatched donor. Patients in the Antigen Matching Study received a cornea with 0 to 6 matched antigens.
Transplant patients were followed intensively during the first months after surgery. The number of clinic visits was tapered to 2 during the third and final year of followup, resulting in a total of 17 postoperative visits. Irreversible failure of the corneal allograft due to all causes was the primary outcome variable in both studies. Allograft reaction episodes, irreversible failure due to rejection, and visual acuity were secondary outcome variables.
|Study Type ICMJE||Interventional|
|Study Phase||Phase 3|
|Study Design ICMJE||Allocation: Randomized
Primary Purpose: Treatment
|Intervention ICMJE||Procedure: Histocompatibility Matching|
|Study Arms||Not Provided|
* Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
|Recruitment Status ICMJE||Completed|
|Enrollment ICMJE||Not Provided|
|Original Enrollment ICMJE||Not Provided|
|Actual Study Completion Date||September 1989|
|Primary Completion Date||Not Provided|
|Eligibility Criteria ICMJE||
Males and females age 10 years or older with two to four quadrants of corneal stroma vascularization or a history of allograft rejection in the eye considered for surgery were eligible for both studies in the CCTS.
Patients must have been willing to participate in 3 years of followup. No one was eligible for the CCTS who had a condition that would greatly increase the risk of nonrejection graft failure, such as xerophthalmia or severe exposure keratopathy. Also excluded were patients with systemic diseases or with medication usage that might alter their immune response.
|Ages||10 Years and older (Child, Adult, Older Adult)|
|Accepts Healthy Volunteers||Not Provided|
|Contacts ICMJE||Contact information is only displayed when the study is recruiting subjects|
|Listed Location Countries ICMJE||Not Provided|
|Removed Location Countries|
|NCT Number ICMJE||NCT00000137|
|Other Study ID Numbers ICMJE||NEI-36|
|Has Data Monitoring Committee||Not Provided|
|U.S. FDA-regulated Product||Not Provided|
|IPD Sharing Statement||Not Provided|
|Responsible Party||Not Provided|
|Study Sponsor ICMJE||National Eye Institute (NEI)|
|Collaborators ICMJE||Not Provided|
|Investigators ICMJE||Not Provided|
|PRS Account||National Eye Institute (NEI)|
|Verification Date||September 2009|
ICMJE Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP