Clinical Research Directory

A Comparative Effectiveness Study in Heart Transplant Patients of Rejection Surveillance With Cell-free DNA Versus Endomyocardial Biopsy

This is an open label Comparative Effectiveness Research (CER) study in which patients will be randomized at the site level to Prospera surveillance or EMB surveillance in a 2:1 ratio (Prospera to EMB) at each site. Subjects will be enrolled into the study while under evaluation for heart transplantation or on the transplant waiting list prior to heart transplantation. All subjects will follow the center's standard of care surveillance schedule from transplant through 4 weeks post-transplantation. EMB during this phase is expected to occur roughly weekly or bi-weekly. Study group assignment will take place at randomization. Subjects will be randomized 30 days (± 10 days) post-transplant to Prospera surveillance versus EMB surveillance in a 2:1 ratio. Rejection surveillance (Prospera Group and EMB Group) will be performed at times corresponding to the institutional standard of care schedule for rejection surveillance.

Valganciclovir vs. Letermovir for CMV Prophylaxis in Heart Transplant

The purpose of this study is to compare the safety and efficacy of letermovir with valganciclovir for prevention of Cytomegalovirus (CMV) viremia in moderate to high risk serostatus heart transplant recipients.

HEARTBiT: Multi-Marker Blood Test for Acute Cardiac Transplant Rejection

Heart transplantation is a life saving therapy for people with end stage heart failure. Acute rejection, a process where the immune system recognizes the transplanted heart as foreign and mounts a response against it, remains a clinical problem despite improvements in immunosuppressive drugs. Acute rejection occurs in 20-30% of patients within the first 3 months post-transplant, and is currently detected by highly invasive heart tissue biopsies that happen 12-15 times in the first year post-transplant. Replacing the biopsy with a simple blood test is of utmost value to patients and will reduce healthcare costs. The goal of our project is to develop a new blood test to monitor heart transplant rejection. Advances in biotechnology have enabled simultaneous measurement of many molecules (e.g., proteins, nucleic acids) in blood, driving the development of new diagnostics. Our team is a leader in using computational tools to combine information from numerous biological molecules and clinical data to generate "biomarker panels" that are more powerful than existing diagnostic tests. Our sophisticated analytic methods has recently derived HEARTBiT, a promising test of acute rejection comprising 9 RNA biomarkers, from the measurement of 30,000 blood molecules in 150 Canadian heart transplant patients. Our objective is to study a custom-built HEARTBiT test in a setting and on a technology that enable clinical adoption. We will evaluate the new test on 400 new patients from 5 North American transplant centres. We will also track patients' HEARTBiT scores over time to help predict future rejection, and explore use of proteins and micoRNAs to improve HEARTBiT. Our work will provide the basis for a future clinical trial. The significance of this work rests in that it will provide a tool to identify acute cardiac rejection in a fast, accurate, cost-effective and minimally invasive manner, allowing for facile long-term monitoring and therapy tailoring for heart transplant patients.

Allograft Dysfunction in Heart Transplant

The investigators will evaluate for early evidence of cardiac allograft dysfunction by cardiac MRI and single cell sequencing to determine underlying molecular and macroscopic causes.

Precision Guided Tacrolimus Dosing in Pediatric Heart Transplant

Immunosuppressive therapy is required to prevent organ rejection, however, dosing of immunosuppressive agents is complicated by patient-specific differences impacting the body's absorption and elimination of these agents. The goal of this research proposal is to clinically validate an innovative precision medicine strategy for dosing the immunosuppressant tacrolimus in pediatric heart transplant, which will in turn lead to improvements in long-term transplant survival outcomes. The strategy and techniques used in this project can be extended to improve drug therapy across multiple pediatric diseases requiring chronic therapy.

Brazilian Clinical Registry of Heart Transplantation

Prospective cohort clinical study, registry-based, multicenter, national, with the consecutive inclusion of patients with a history of Heart Transplantation in Brazil. The clinical registry will involve the participation until 25 centers. Patients will be included up to 30 days after Heart Transplant surgery and will be followed for one year. Laboratory tests and clinical parameters wil be collected in two clinical visits (6mo and 12 mo). The outcomes evaluate will be the total hospitalizations and all-cause death. It is expected to include 730 patients with a 12-month follow-up from the day of the transplant surgery. The findings of the HESTIA Registry may guide the management of post-heart transplant patients, aiming at reducing morbidity and mortality within 12 months after heart transplant surgery.

A Clinical Study of Association Between Postoperative Dyslipidemia and Organ Rejection in Transplant Patients

Abnormal lipid metabolism is a common complication after organ transplantation, with pathological changes in lipid parameters occurring in approximately 60-80% of cardiac transplant recipients receiving triple immunotherapy with cyclosporine, imid azathioprine, and methylprednisolone. With the significant increase in long-term survival and increasing age of transplant patients, atherosclerotic cardiovascular diseases, such as those caused by dyslipidemia, have become a major cause of transplant organ failure and recipient death. However, the causes of dyslipidemia after organ transplantation, as well as the effects and mechanisms of dyslipidemia on transplant rejection, are unknown. Previous studies have found that 1. increased lipid levels occur in recipients after heart transplantation; 2. during rejection, hepatic PCSK9 expression is increased in recipients; 3. a high-fat environment increases the immunoreactivity of human peripheral blood lymphocytes. It is suggested that PCSK9-lipid disorder-immune cell interactions may be associated with the development of transplant rejection. In this project, we propose to (1) establish a long-term follow-up system for postoperative cardiac transplantation patients in our department to track the characteristics of lipid changes in transplantation patients, to clarify the link between dyslipidemia and rejection, and to provide a strong evidence-based medical basis for the management of lipids during the perioperative period and in the postoperative period; (2) expand the dimensions of lipid-related assays under the support of the above system, and to incorporate transcriptomic, proteomic, and metabolomic research methods to elucidate transplantation rejection in a multidimensional manner. (ii) Expanding the dimensions of lipid-related assays to include transcriptomic, proteomic, and metabolomic studies to elucidate the relationship between PCSK9 and dyslipidemia in transplant patients; (iii) Adopting single-cell sequencing technology to deeply reveal the potential mechanism by which changes in lipids affect T-cell-mediated rejection of cardiac transplants. The mechanism of T-cell-mediated cardiac transplantation rejection is revealed by single-cell sequencing.