Meta-Analysis Shows Clinical Benefits of HOPE in Liver Transplantation

A recent Cochrane review and meta-analysis has revealed substantial benefits of hypothermic oxygenated machine perfusion (HOPE) for livers awaiting transplantation over normothermic machine perfusion (NMP) and static cold storage (SCS). Conducted by Samuel James Tingle, MD, and his team at Newcastle University, the study evaluated data from seven clinical trials involving 1,024 transplant recipients out of 1,301 randomized livers. The findings were presented during a late-breaker session at the 2024 International Congress of the International Liver Transplantation Society (ILTS) in Houston, Texas.

The analysis focused on comparing end-ischemic HOPE and NMP with SCS. Four trials compared HOPE with SCS, while three compared NMP with SCS. The results showed that HOPE significantly improved several clinically relevant outcomes compared to SCS. Specifically, HOPE was linked to better graft survival (HR=0.45, 95% CI=0.23-0.87; P=0.02; high-certainty evidence), fewer serious adverse events (OR=0.45, 0.22-0.91; P=0.03; moderate-certainty evidence), and a lower incidence of clinically significant ischemic cholangiopathy (OR=0.31, 0.11-0.92; P=0.03; high-certainty evidence). In contrast, NMP did not show similar benefits over SCS in these outcomes.

Lead author Samuel James Tingle, MD, highlighted that end-ischemic HOPE provides superior clinically relevant outcomes compared to SCS for DCD (donation after cardiac death) or marginal DBD (donation after brain death) livers. However, he noted that while NMP could potentially increase the utilization of grafts that might otherwise be discarded, further well-powered trials are necessary to evaluate this aspect comprehensively.

The research team utilized Cochrane's robust search methods and systematic review processes to identify relevant randomized machine perfusion trials. Data extraction was carried out independently by two authors, and pairwise random-effects meta-analysis was employed. The risk of bias was assessed using Risk of Bias 2, and the certainty of evidence was evaluated using GRADE.

Don Webber, CEO of Bridge to Life Ltd, expressed satisfaction with the meta-analysis results. He stated that the findings align with the company's observations from real-world scenarios outside the United States, where their VitaSmart system has been in use. Webber emphasized the system's user-friendly design and competitive pricing, which have made it a popular choice among transplant centers. He also mentioned plans to share their data with the FDA later this year.

Machine perfusion (MP) is an innovative technique for preserving organ grafts prior to transplantation. In the context of HOPE, donor livers are perfused via the portal vein with a cold, acellular, oxygenated fluid at low vascular pressures. This method aims to mitigate non-anastomotic biliary strictures (NAS), which are postoperative complications often seen in liver transplant patients.

Bridge to Life Ltd is a leading provider of organ preservation solutions, offering products like Belzer UW, EasiSlush, and the VitaSmart hypothermic oxygenated perfusion system. The company is committed to quality, innovation, and accessibility, partnering with top transplant centers and organ procurement offices worldwide. VitaSmart is currently available in several markets outside the United States and is awaiting FDA approval following the completion of a pivotal multicenter randomized clinical study in 2023.