Preliminary Results From A Non-Inferiority Trial: Novel Hypothermic Conservation Medium Xtra4 Vs. Standard Eusol-C
Published 2026 - 44th Congress of the ESCRS
Reference: POCOR283 | Type: Free paper | DOI: 10.82333/qrrg-eh23
Authors: Dr Valentin Jünger* 1 , Dr Andrea Margarella 2 , A/Prof. Carlo Nucci 3 , Dr Rossella Anna Maria Gisoldi Colabelli 4 , A/Prof. Augusto Pocobelli 4
1Department of Ophthalmology and Experimental Medicine,University of Rome Tor Vergata,Rome,Italy;Department of Ophthalmology,Rome Eye Bank, San Giovanni Addolorata Hospital,Rome ,Italy, 2Department of Clinical Medicine, Public health, Life and Environmental Sciences,University of L’Aquila,L’Aquila,Italy;Department of Ophthalmology,Rome Eye Bank, San Giovanni Addolorata Hospital,Rome,Italy, 3Department of Ophthalmology and Experimental Medicine,University of Rome Tor Vergata,Rome,Italy, 4Department of Ophthalmology,Rome Eye Bank, San Giovanni Addolorata Hospital,Rome,Italy
Purpose
Standard hypothermic corneal storage is limited to 14 days and is associated with progressive tissue swelling over time. Hyperthermic (organ culture) storage allows preservation up to 28 days but requires a deswelling phase before transplantation, limiting its suitability for urgent surgery. XTRA4, a novel hypothermic corneal preservation medium, has demonstrated promising preclinical results in maintaining physiological corneal thickness and endothelial integrity beyond 14 days and may provide the necessary logistical flexibility for urgent surgery; however, clinical post-transplant outcomes have not yet been evaluated.
Setting
This prospective, randomized, controlled, single-center non-inferiority trial is the first clinical post-transplant investigation evaluating the safety and performance of XTRA4 versus Corneal Chamber (AL.CHI.MI.A. SRL, Moria Group) in patients undergoing endothelial keratoplasty (EK) under routine clinical practice conditions
Methods
9 patients undergoing EK (4 DMEK; 5 DSAEK) received donor corneas stored in XTRA4 and 9 patients tissues stored in Corneal Chamber (3 DMEK; 6 DSAEK). The primary endpoint was relative reduction of recipient central corneal thickness (rrCCT) at 1 month postoperatively. Secondary endpoints included relative changes in pre-transplant donor central corneal thickness (dCCT) and relative changes in donor endothelial cell density (dECD) during tissue preservation; postoperative recipient CCT, and graft detachment with indication for rebubbling. Safety endpoints included adverse events and primary graft failure.
Results
Preliminary analysis demonstrated no statistically significant difference in the primary endpoint rrCCT at 1 month (XTRA4: 23,7%; Corneal Chamber: 23,4%; p=0,97), meeting non-inferiority criteria. No significant differences were observed in donor dCCT (XTRA4: 564 µm ; Corneal Chamber: 608µm; p=0,14) and dECD (XTRA4: 2601 cells/mm2; Corneal Chamber: 2544 cells/mm2; p=0,16), postoperative recipient CCT (XTRA4: 545,75 µm ; Corneal Chamber: 574,75 µm; p=0,45) or rebubbling rates. EK outcomes were consistent with expected standards in both groups. No unexpected device-related adverse events were reported. Six-month follow-up is ongoing
Conclusions
XTRA4 demonstrated non-inferior clinical performance compared with Corneal Chamber, maintaining donor corneal quality and supporting favorable early postoperative outcomes after EK. Preliminary findings confirm its safety and suitability for hypothermic storage and indicate a beneficial performance in long-term storage. By enabling extended cold preservation with tissue ready for immediate use, XTRA4 may provide increased flexibility for eye banks, facilitating urgent surgical scheduling without the delays associated with warm storage deturgescence. Completion of follow-up will further clarify its long-term clinical impact.