Immunosuppressive Agents and Infectious Risk in Transplantation: Managing the "Net State of Immunosuppression".
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ABSTRACT: Successful solid organ transplantation reflects meticulous attention to the details of immunosuppression, balancing risks for graft rejection against risks for infection. The "net state of immune suppression" is a conceptual framework of all factors contributing to infectious risk. Assays that measure immune function in the immunosuppressed transplant recipient relative to infectious risk and allograft function are lacking. The best measures of integrated immune function may be quantitative viral loads to assess the individual's ability to control latent viral infections. Few studies address adjustment of immunosuppression during active infections; thus, confronted with infection in solid organ recipients, the management of immunosuppression is based largely on clinical experience. This review examines known measures of immune function and the immunologic effects of common immunosuppressive drugs and available studies reporting modification of drug regimens for specific infections. These data provide a conceptual framework for the management of immunosuppression during infection in organ recipients.
Project description:Excellent outcomes have been achieved in the field of renal transplantation. A significant reduction in acute rejection has been attained at many renal transplant centers using contemporary immunosuppressive, consisting of an induction agent, a calcineurin inhibitor, an antiproliferative agent plus or minus a corticosteroid. Despite improvements with these regimens, chronic allograft injury and adverse events still persist. The perfect immunosuppressive regimen would limit or eliminate calcineurin inhibitors and/or corticosteroid toxicity while providing enhanced allograft outcomes. Potential improvements to the calcineurin inhibitor class include a prolonged release tacrolimus formulation and voclosporin, a cyclosporine analog. Belatacept has shown promise as an agent to replace calcineurin inhibitors. A novel, fully-human anti-CD40 monoclonal antibody, ASKP1240, is currently enrolling patients in phase 2 trials with calcineurin minimization and avoidance regimens. Another future goal of transplant immunosuppression is effective and safe treatment of allograft rejection. Novel treatments for antibody mediated rejection include bortezomib and eculizumab. Several investigational agents are no longer being pursed in transplantation including the induction agents, efalizumab and alefacept, and maintenance agents, sotrastaurin and tofacitinib. The purpose of this review is to consolidate the published evidence of the effectiveness and safety of investigational immunosuppressive agents in renal transplant recipients.
Project description:BackgroundMajor hurdles for survival after lung transplantation are rejections and infectious complications. Adequate methods for monitoring immune suppression status are lacking. Here, we evaluated quantification of torque teno virus (TTV) and Epstein-Barr virus (EBV) as biomarkers for defining the net state of immunosuppression in lung-transplanted patients.MethodsThis prospective single-center study included 98 patients followed for 2 years after transplantation. Bacterial infections, fungal infections, viral respiratory infections (VRTI), cytomegalovirus (CMV) viremia, and acute rejections, as well as TTV and EBV levels, were monitored.ResultsThe levels of torque teno virus DNA increased rapidly after transplantation, likely due to immunosuppressive treatment. A modest increase in levels of Epstein-Barr virus DNA was also observed after transplantation. There were no associations between either TTV or EBV and infectious events or acute rejection, respectively, during follow-up. When Tacrolimus was the main immunosuppressive treatment, TTV DNA levels were significantly elevated 6-24 months after transplantation as compared with Cyclosporine treatment.ConclusionsAlthough replication of TTV, but not EBV, appears to reflect the functionality of the immune system, depending on the type of immunosuppressive treatment, quantification of TTV or EBV as biomarkers has limited potential for defining the net state of immune suppression.
Project description:Cancer is a widely recognized complication of transplantation, and the effects of various immunosuppressive drugs on cancer risk remains controversial. This randomized trial allocated 489 recipients of first cadaveric renal transplants to one of three groups: Azathioprine and prednisolone, cyclosporine monotherapy, or cyclosporine monotherapy followed by a switch to azathioprine and prednisolone after 3 months. Here, we report cancer outcomes by non-skin cancer (including melanoma) and skin cancer (excluding melanoma) for 481 patients during a median follow-up of 20.6 years. A total of 226 patients developed at least one cancer: 95 with non-skin cancer and 171 with skin cancer. In the intention-to-treat analysis, mean times to first non-skin cancer (16.0, 15.3, and 15.7 years for groups 1 through 3, respectively) and first skin cancer (13.6, 14.3, and 15.2 years, respectively) were not different among the three groups or between any subgroup. In multivariate analyses, non-skin cancer associated with increasing age and previous smoking history, whereas skin cancer associated with increasing age, nonbrown eye color, fairer skin, and a functioning transplant. Treatment allocation did not associate with development of either form of cancer in multivariate analyses. In conclusion, these immunosuppressive regimens, widely used in recent decades, carry similar risks for carcinogenicity after kidney transplantation.
Project description:The decision algorithm for treatment of advanced myelodysplastic syndrome (MDS) (intermediate- to very high-risk by the revised International Prognostic Scoring System [IPSS-R]) is complex. Often, the appropriate choice is unknown and not currently addressed by available clinical evidence. Although allogeneic hematopoietic cell transplantation (alloHCT) is curative for some patients with MDS, there is a concurrent high risk of mortality and morbidity. Alternatively, although hypomethylating agents (HMAs) have low toxicity, they are not thought to be curative, with a median increase in overall survival of only 9 months. Initial attempts to improve outcomes with HMAs through addition of novel agents failed, but there is hope that newer combination strategies will improve outcomes. Challenging clinical questions include who should be considered for alloHCT, appropriate timing and preparation for alloHCT, and appropriate therapeutic choices for patients who are not candidates for alloHCT. Given the interplay between alloHCT and non-alloHCT approaches, a unified coordinated approach is optimal for patients with advanced MDS. When possible, patients with advanced MDS should be encouraged to enroll into clinical trials that include alloHCT and non-alloHCT approaches.
Project description:Islet transplantation can temporarily cure type 1 diabetes mellitus (T1DM) but requires simultaneous immunosuppression to avoid allograft rejection. In this issue of the JCI, Monti et al. report that immune conditioning via use of the Edmonton protocol - a treatment approach in which T1DM patients infused with pancreatic islets from multiple cadaveric donors simultaneously receive immunosuppressive drugs - results in lymphopenia that is associated with elevated serum levels of the homeostatic cytokines IL-7 and IL-15, which causes in vivo expansion of the autoreactive CD8(+) T cell population (see the related article beginning on page 1806). Reemergence of autoreactivity is likely the main culprit underlying long-term islet graft failure, and new strategies will need to be tested to circumvent this homeostatic expansion and recurrent autoreactivity.
Project description:Rationale & objectiveDisorders of bone and mineral metabolism frequently develop with advanced kidney disease, may be exacerbated by immunosuppression after kidney transplantation, and increase the risk of fractures.Study designRetrospective database study.Setting & participantsKidney-only transplant recipients aged ≥18 years from 2005 to 2016 in the United States captured in US Renal Data System records, which integrate Organ Procurement and Transplantation Network/United Network for Organ Sharing records with Medicare billing claims.ExposuresVarious immunosuppression regimens in the first 3 months after kidney transplantation.OutcomesThe development of fractures, as ascertained using diagnostic codes on Medicare billing claims.Analytical approachWe used multivariable Cox regression with inverse propensity weighting to compare the incidence of fractures >3 months-to-3 years after kidney transplantation associated with various immunosuppression regimens compared to a reference regimen of antithymocyte globulin (TMG) or alemtuzumab (ALEM) with tacrolimus + mycophenolic acid + prednisone using inverse probability treatment weighting.ResultsOverall, fractures were identified in 7.5% of kidney transplant recipients (women, 8.8%; men, 6.7%; age < 55 years, 5.9%; age ≥ 55 years, 9.3%). In time-varying regression, experiencing a fracture was associated with a substantially increased risk of subsequent death within 3 months (adjusted hazard ratio [aHR], 3.06; 95% confidence interval [CI], 2.45-3.81). Fractures were also associated with increased Medicare spending (first year: $5,122; second year: $10,890; third year: $11,083; [P < 0.001]). Induction with TMG or ALEM and the avoidance or early withdrawal of steroids significantly reduced the risk of fractures in younger (aHR, 0.63; 95% CI, 0.54-0.73) and older (aHR, 0.83; 95% CI, 0.74-0.94) patients. The avoidance or early withdrawal of steroids with any induction was associated with a reduced risk of fractures in women.LimitationsThis was a retrospective study which lacked data on immunosuppression levels.ConclusionsFractures after kidney transplantation are associated with significantly increased mortality risk and costs. The early avoidance or early withdrawal of steroids after induction with TMG or ALEM reduces the risk of fractures after kidney transplantation and should be considered for patients at high-risk of this complication, including older adults and women.
Project description:Hematopoietic stem cell transplantation (HSCT) is often the only curative treatment option for patients suffering from various types of malignant diseases and some non-cancerous conditions. Nevertheless, it is associated with a high risk of complications leading to transplant-related mortality and long-term morbidity. An increasing number of therapeutic and prevention strategies have been developed over the last few years to tackle the complications arising in patients receiving an HSCT. These strategies have been mainly carried out in adults and some are now being translated into children. In this manuscript, we review the recent advancements in the development and implementation of treatment options for post-HSCT non-infectious complications in pediatric patients with leukemia and other non-malignant conditions, with a special attention on the new agents available within clinical trials. We focused on the following conditions: graft failure, prevention of relapse and early interventions after detection of minimal residual disease positivity following HSCT in acute lymphoblastic and myeloid leukemia, chronic graft versus host disease, non-infectious pulmonary complications, and complications of endothelial origin.
Project description:This study was conducted to elucidate the influence of immunosuppressive treatment (IST) and GVHD on risk of recurrent malignancy after allogeneic hematopoietic cell transplantation (HCT). The study cohort included 2656 patients who received allogeneic HCT after high-intensity conditioning regimens for treatment of hematologic malignancies. Rates and hazard ratios of relapse and mortality were analyzed according to GVHD and IST as time-varying covariates. Adjusted Cox analyses showed that acute and chronic GVHD were both associated with statistically similar reductions in risk of relapse beyond 18 months after HCT but not during the first 18 months. In patients with GVHD, resolution of GVHD followed by withdrawal of IST was not associated with a subsequent increase in risk of relapse. In patients without GVHD, withdrawal of IST was associated with a reduced risk of relapse during the first 18 months, but the risk of subsequent relapse remained considerably higher than in patients with GVHD. In summary, the association of GVHD with risk of relapse changes over time after HCT. In patients without GVHD, early withdrawal of IST might help to prevent relapse during the first 18 months, but other interventions would be needed to prevent relapse at later time points.