A Randomized Trial Comparing Imlifidase to Plasmapheresis in Kidney Transplant Recipients With Antibody-Mediated Rejection.

BACKGROUND: Antibody-mediated rejection (ABMR) poses a barrier to long-term graft survival and is one of the most challenging events after kidney transplantation. Removing donor specific antibodies (DSA) through therapeutic plasma exchange (PLEX) is a cornerstone of antibody depletion but has inconsistent effects. Imlifidase is a treatment currently utilized for desensitization with near-complete inactivation of DSA both in the intra- and extravascular space. METHODS: This was a 6-month, randomized, open-label, multicenter, multinational trial conducted at 14 transplant centers. Thirty patients were randomized to either imlifidase or PLEX treatment. The primary endpoint was reduction in DSA level during the 5 days following the start of treatment. RESULTS: Despite considerable heterogeneity in the trial population, DSA reduction as defined by the primary endpoint was 97% for imlifidase compared to 42% for PLEX. Additionally, imlifidase reduced DSA to noncomplement fixing levels, whereas PLEX failed to do so. After antibody rebound in the imlifidase arm (circa days 6-12), both arms had similar reductions in DSA. Five allograft losses occurred during the 6 months following the start of ABMR treatment-four within the imlifidase arm (18 patients treated) and one in the PLEX arm (10 patients treated). In terms of clinical efficacy, the Kaplan-Meier estimated graft survival was 78% for imlifidase and 89% for PLEX, with a slightly higher eGFR in the PLEX arm at the end of the trial. The observed adverse events in the trial were as expected, and there were no apparent differences between the arms. CONCLUSION: Imlifidase was safe and well-tolerated in the ABMR population. Despite meeting the primary endpoint of maximum DSA reduction compared to PLEX, the trial was unsuccessful in demonstrating a clinical benefit of imlifidase in this heterogenous ABMR population. TRIAL REGISTRATION: EudraCT number: 2018-000022-66, 2020-004777-49; ClinicalTrials.gov identifier: NCT03897205, NCT04711850.

The evolving use of biomarkers in heart transplantation: Consensus of an expert panel.

In heart transplantation, the use of biomarkers to detect the risk of rejection has been evolving. In this setting, it is becoming less clear as to what is the most reliable test or combination of tests to detect rejection and assess the state of the alloimmune response. Therefore, a virtual expert panel was organized in heart and kidney transplantation to evaluate emerging diagnostics and how they may be best utilized to monitor and manage transplant patients. This manuscript covers the heart content of the conference and is a work product of the American Society of Transplantation's Thoracic and Critical Care Community of Practice. This paper reviews currently available and emerging diagnostic assays and defines the unmet needs for biomarkers in heart transplantation. Highlights of the in-depth discussions among conference participants that led to development of consensus statements are included. This conference should serve as a platform to further build consensus within the heart transplant community regarding the optimal framework to implement biomarkers into management protocols and to improve biomarker development, validation and clinical utility. Ultimately, these biomarkers and novel diagnostics should improve outcomes and optimize quality of life for our transplant patients.

IL-6 receptor blockade for allograft dysfunction after lung transplantation in a patient with COPA syndrome.

OBJECTIVE: COPA syndrome is a genetic disorder of retrograde cis-Golgi vesicle transport that leads to upregulation of pro-inflammatory cytokines (mainly IL-1ß and IL-6) and the development of interstitial lung disease (ILD). The impact of COPA syndrome on post-lung transplant (LTx) outcome is unknown but potentially detrimental. In this case report, we describe progressive allograft dysfunction following LTx for COPA-ILD. Following the failure of standard immunosuppressive approaches, detailed cytokine analysis was performed with the intention of personalising therapy. METHODS: Multiplexed cytokine analysis was performed on serum and bronchoalveolar lavage (BAL) fluid obtained pre- and post-LTx. Peripheral blood mononuclear cells (PMBCs) obtained pre- and post-LTx were stimulated with PMA, LPS and anti-CD3/CD28 antibodies. Post-LTx endobronchial biopsies underwent microarray-based gene expression analysis. Results were compared to non-COPA LTx recipients and non-LTx healthy controls. RESULTS: Multiplexed cytokine analysis showed rising type I/II IFNs, and IL-6 in BAL post-LTx that decreased following treatment of acute rejection but rebounded with further clinical deterioration. In vitro stimulation of PMBCs suggested that myeloid cells were driving deterioration, through IL-6 signalling pathways. Tocilizumab (IL-6 receptor antibody) administration for 3 months (4 mg kg-1, monthly) effectively suppressed IL-6 levels in BAL. Mucosal gene expression profile following tocilizumab suggested greater similarity to normal. CONCLUSION: Clinical effectiveness of IL-6 receptor blockade was not observed. However, we identified IL-6 upregulation associated with graft injury, effective IL-6 suppression with tocilizumab and evidence of beneficial effect on molecular transcripts. This mechanistic analysis suggests a role for IL-6 blockade in post-LTx care that should be investigated further.

Efficacy and safety of colonic stenting for malignant disease in the elderly.

BACKGROUND: Self-expandable metal stents (SEMS) are an accepted palliation for malignant colorectal obstruction. Outcomes of stent insertion solely in older patients are unknown. OBJECTIVE: To compare outcomes of SEMS insertion for malignant colorectal disease, in older versus younger patients. METHODS: Forty-three patients were retrospectively identified as having undergone SEMS insertion for obstructing colorectal cancer. Of these, 24 were > or = 70 years of age (older patient group) and 19 were <70 years of age (younger patient group). RESULTS: There was no significant difference in successful SEMS insertion between the groups (88% in older versus 100% in younger patients, p > 0.05). Furthermore, the complication rate was similar in both groups (12.5% versus 26%, p > 0.10). There was no difference in median survival (113 days versus 135 days, p > 0.09). CONCLUSION: Colorectal stenting for malignant disease in older patients is both safe and effective with comparative success and complication rates to a younger population.

A randomized, controlled trial of daclizumab vs anti-thymocyte globulin induction for lung transplantation.

BACKGROUND: Rejection remains a significant cause of morbidity and mortality after lung transplantation. The purpose of this study was to test the efficacy and safety of daclizumab (DZM) vs anti-thymocyte globulin (ATG) as a component of induction therapy. METHODS: Fifty adults undergoing lung transplantation were randomized to receive either ATG or DZM during induction therapy. Patients were followed for 1 year after transplant. RESULTS: Although there was no significant difference in the number of acute or chronic rejections between groups, there was a trend toward a delay in time to first acute rejection with DZM induction. Average absolute lymphocytes and average platelet count were significantly higher in the DZM group. Cytomegalovirus (CMV) serology mismatch was higher in the DZM group (7 vs 1, p = 0.05). The DZM group had a greater number of infections (83 vs 47, p = 0.02); however, the number of CMV infections was also significantly greater (18 vs 6, p = 0.03), corresponding to a higher incidence of CMV mismatch. A cost analysis revealed no difference between total drug costs, intensive-care unit (ICU) costs and total hospital costs. One-year survival was 96% in the DZM group and 88% in the ATG group. CONCLUSIONS: DZM is a safe component of induction therapy in lung transplantation. In addition, DZM may prolong freedom from acute rejection. Significant infections were more frequent in the DZM group, but this was likely due to a higher incidence of CMV mismatch. Both methods of induction therapy worked well, with excellent 1-year survival.