Timing of basiliximab induction and development of acute rejection in lung transplant patients

Current perspective of immunomodulators for lung transplant

Lung transplantation is an effective treatment option for selected patients suffering from end-stage lung disease. More intensive immunosuppression is enforced after lung transplants owing to a greater risk of rejection than after any other solid organ transplants. The commencing of lung transplantation in the modern era was in 1983 when the Toronto Lung Transplant Group executed the first successful lung transplant. A total of 43,785 lung transplants and 1365 heart-lung transplants have been performed from 1 Jan 1988 until 31 Jan 2021. The aim of this review article is to discuss the existing immunosuppressive strategies and emerging agents to prevent acute and chronic rejection in lung transplantation.

Review: immunosuppression for the lung transplant patient

Lung transplantation (LTx) has evolved significantly since its inception and the improvement in LTx outcomes over the last three decades has predominantly been driven by advances in immunosuppression management. Despite the lack of new classes of immunosuppression medications, immunosuppressive strategies have evolved significantly from a universal method to a more targeted approach, reflecting a greater understanding of the need for individualized therapy and careful consideration of all factors that are influenced by immunosuppression choice. This has become increasingly important as the demographics of lung transplant recipients have changed over time, with older and more medically complex candidates being accepted and undergoing LTx. Furthermore, improved survival post lung transplant has translated into more immunosuppression related comorbidities long-term, predominantly chronic kidney disease (CKD) and malignancy, which has required further nuanced management approaches. This review provides an update on current traditional lung transplant immunosuppression strategies, with modifications based on pre-existing recipient factors and comorbidities, peri-operative challenges and long term complications, balanced against the perpetual challenge of chronic lung allograft dysfunction (CLAD). As we continue to explore and understand the complexity of LTx immunology and the interplay of different factors, immunosuppression strategies will require ongoing critical evaluation and personalization in order to continue to improve lung transplant outcomes.

A virtual crossmatch-based strategy for perioperative desensitisation in lung transplant recipients with preformed donor-specific antibodies: 3-year outcome

BACKGROUND

Preformed donor-specific antibodies (DSAs) are associated with worse outcome after lung transplantation (LTx) and migvaht limit access to LTx. A virtual crossmatch (CXM)-based strategy for perioperative desensitisation protocol has been used for immunised LTx candidates since 2012 at Foch hospital. We compared the outcome of desensitised LTx candidates with high DSA mean fluorescence intensity (MFI) and those with low or no preformed DSAs, not desensitised.

METHODS

For all consecutive LTx recipients (January-2012/March-2018), freedom from CLAD and graft survival were assessed by Kaplan-Meier analysis and Cox multivariate analysis.

RESULTS

We compared outcomes for desensitised patients with high preformed DSAs (n=39) and those with no (n=216) or low pre-formed DSAs (n=66). The desensitisation protocol decreased the level of immunodominant DSA (class I/II) at 1, 3, and 6 month post-LTx (p<0.001, p<0.01, p<0.001, respectively). Freedom from CLAD and graft survival at 3 years was similar in the desensitised group as a whole and other groups. Nevertheless, incidence of CLAD was higher with persistent high- than cleared high-level (p=0.044) or no DSAs (p=0.014). Conversely, graft survival was better with cleared high DSAs than persistent high-, low-level, and no pre-formed DSAs (p=0.019, p=0.025, and p=0.044, respectively). On multivariate analysis, graft survival was associated with cleared high DSAs (HR: 0.12 [95%CI: 0.02-0.85] versus no DSAs, p=0.035) and CLAD with persistent DSAs (HR: 3.04 [1.02-9.17] versus no preformed DSAs, p=0.048).

CONCLUSION

The desensitisation protocol in LTx recipients with high preformed DSAs was associated with satisfactory outcome, with cleared high pre-formed DSAs after desensitisation identified as an independent predictor of graft survival.

Impact of induction strategy change on first-year rejection in pediatric heart transplantation at a single center-From postoperative basiliximab to either postoperative anti-thymocyte globulin or preoperative basiliximab

BACKGROUND

Our pediatric heart transplant center transitioned from post-bypass basiliximab (BAS) induction to either anti-thymocyte globulin (ATG) or pre-bypass BAS. The purpose of this study was to compare first-year rejection rates before and after this change.

METHODS

A single-center retrospective analysis was conducted of pediatric heart transplant recipients from 2010 to 2019. Primary outcome was first-year rejection. Bivariate analysis, Kaplan-Meier curves, and multivariable regression were performed across eras.

RESULTS

Forty-three early era patients (55%) received post-bypass BAS, and 35 late era patients (45%) received pre-bypass BAS (n = 17) or ATG (n = 18). First-year rejection decreased in the late era (31% vs 53%, p = .05). This finding was more pronounced after excluding infants (38% vs 73%, p = .006). Late era was associated with a decreased likelihood of rejection (all cohort OR 0.19, 95% CI 0.05-0.66; infants excluded OR 0.17, 95% CI 0.04-0.61). No differences in post-transplant lymphoproliferative disease, donor-specific antibody, or infection were observed.

CONCLUSIONS

Fewer late era patients receiving ATG or pre-bypass BAS induction had first-year rejection compared to the early era patients receiving standard post-bypass BAS induction. This programmatic shift in induction strategy was readily achievable and potentially effective in reducing first-year rejection.

Association between diverticular disease requiring surgical intervention and mortality in the postlung transplant population - a retrospective cohort study

Lung Transplant recipients are at increased risk of complicated diverticular disease. We aim to assess the rate of diverticular surgery in a postlung transplantation population and identify risk factors for surgery. We performed a retrospective cohort study of lung transplant recipients from 2007 to 2011. Demographic variables were evaluated with the Mann-Whitney U and chi-squared tests. Cox regression was performed to evaluate 1- and 2-year landmark survival, assess predictor variables of diverticular surgery and evaluate impact of surgery on CLAD development. Of 17 of 158 patients (10.7%) underwent diverticular-related surgery. Surgical patients had significantly worse survival than nonsurgical patients at 1 year [aHR 2.93 (1.05-8.21), P = 0.041] and 2 year [aHR 4.17 (1.26-13.84), P = 0.020] landmark analyses. Transplant indication of alpha-1 antitrypsin disease and cystic fibrosis were significantly associated with the need for diverticular surgery. Emergent surgery was associated with poorer survival [aHR 5.12(1.00-26.27), P = 0.050]. Lung transplant patients requiring surgery for complicated diverticular disease have significantly poorer survival than those who do not require surgery. Surgery was more common in patients transplanted for A1AT and CF. Optimal assessment and risk stratification of diverticular disease is necessary to prevent excessive morbidity and mortality following transplantation.

New frontiers in immunosuppression

Immunosuppressive therapy is arguably the most important component of medical care after lung transplantation. The goal of immunosuppression is to prevent acute and chronic rejection while maximizing patient survival and long-term allograft function. However, the benefits of immunosuppressive therapy must be balanced against the side effects and major toxicities of these medications. Immunosuppressive agents can be classified as induction agents, maintenance therapies, treatments for acute rejection and chronic rejection and antibody directed therapies. Although induction therapy remains an area of controversy in lung transplantation, it is still used in the majority of transplant centers. On the other hand, maintenance immunosuppression is less contentious; but, unfortunately, since the creation of three-drug combination therapy, including a glucocorticoid, calcineurin inhibitor and anti-metabolite, there have been relatively modest improvements in chronic maintenance immunosuppressive regimens. The presence of HLA antibodies in transplant candidates and development of de novo antibodies after transplantation remain a major therapeutic challenge before and after lung transplantation. In this chapter we review the medications used for induction and maintenance immunosuppression along with their efficacy and side effect profiles. We also review strategies and evidence for HLA desensitization prior to lung transplantation and management of de novo antibody formation after transplant. Finally, we review immune tolerance and the future of lung transplantation to limit the toxicities of conventional immunosuppressive therapy.

Basiliximab application on liver recipients: a meta-analysis of randomized controlled trials

BACKGROUND

The benefits of the application of basiliximab induction therapy in liver transplantation are not clear. The present meta-analysis was to evaluate the pros and cons of basiliximab use in liver transplantation.

DATA SOURCES

We searched the associated publications in English from July 1998 to December 2015 in the following databases: MEDLINE, PubMed, Ovid, EMBASE, Web of Science and Cochrane Library.

RESULTS

Basiliximab significantly decreased the incidence of de novo diabetes mellitus after liver transplantation (RR=0.56; 95% CI: 0.34-0.91; P=0.02). Subgroup analysis showed that basiliximab in combination with steroids-free immunosuppressant significantly decreased the incidence of biopsy-proven acute rejection (RR=0.62; 95% CI: 0.39-0.97; P=0.04) and new-onset hypertension (RR=0.62; 95% CI: 0.42-0.93; P=0.02).

CONCLUSIONS

Basiliximab may be effective in reducing de novo diabetes mellitus. What is more, basiliximab in combination with steroids-free immunosuppressant shows statistical benefit to reduce biopsy-proven acute rejection and de novo hypertension.

Rescue alemtuzumab for refractory acute cellular rejection and bronchiolitis obliterans syndrome after lung transplantation

Refractory acute cellular rejection (rACR) is associated with death and bronchiolitis obliterans syndrome (BOS) post-lung transplantation. We report the largest cohort of lung transplant recipients (LTRs) treated with rescue alemtuzumab for rACR or BOS. RACR outcomes included burden of ACR 30 days before and 180 days after rescue assessed by a novel composite rejection standardized score (CRSS, range 0-6) and freedom from ≥A2 ACR. BOS outcomes included freedom from BOS progression and FEV1 decline >10%. Univariate parametric and nonparametric statistical approaches were used to assess treatment response. Kaplan-Meier method with log rank conversion was used to assess freedom from events. Fifty-seven alemtuzumab doses (ACR 40 and BOS 17) given to 51 patients were included. Median time to rescue was 722 (IQR 42-1403) days. CRSS declined significantly (3 vs 0.67, P<0.001) after rescue. Freedom from ≥A2 was 62.5% in rACR. Freedom from BOS progression was 52.9% at 180 days in the BOS cohort. Freedom from FEV1 decline >10% was 70% in BOS grade 1 and 14.3% in advanced BOS grades 2-3. Infections developed in 72.5% and 76.5% of rACR and BOS groups. Rescue alemtuzumab appears useful for rACR. Patients with BOS 1 may have transient benefit, and patients with advanced BOS seem not to respond to alemtuzumab.

Efficacy and safety of basiliximab in liver transplantation for patients with hepatitis B virus-related diseases: a single centre study

AIMS

We aim to evaluate the efficacy and safety of basiliximab in liver transplantation (LT) for patients with hepatitis B virus-related diseases.

METHODS

A total of 268 patients with hepatitis B virus-related diseases undergoing LT were enrolled and divided into two groups according to the usage of basiliximab. Total survival, the survival of high-risk patients defined by the posttransplant model for predicting mortality, acute rejection rate, biochemical parameters and other follow-up data were compared between the two groups.

RESULTS

Group Bas was composed of 131 patients who received basiliximab, and Group Triple enrolled the other 137 patients who did not. Between the two groups, there was no significant difference in the cumulative survival of patients without hepatocellular carcinoma (HCC) or in the cumulative survival of patients with HCC. For patients with benign end-stage liver diseases, Group Bas had more patients with a high risk of short- and medium-term mortality than Group Triple (22.81% vs. 8.85%, p = 0.017), but the survival curves of the two groups were not significantly different. The 1-year incidence of acute rejection was lower in Group Bas, although the difference was not significant (8.75% vs. 15.33%, p > 0.05). In both Group Bas and Group Triple, the level of serum creatinine (Scr) at 1 week posttransplantation was significantly lower than pretransplantation (61.00 vs. 88.50 μmol/l, p < 0.001; 61.50 vs. 74.00 μmol/l, p < 0.001; respectively). There was a significant difference in the pretransplantation Scr between the two groups (88.50 vs. 74.00 μmol/l, p = 0.005), but the values of Scr decreased to the same level 1 week (61.00 vs. 61.50 μmol/l, p > 0.05) and 4 weeks (61.00 vs. 59.00 μmol/l, p > 0.05) after transplantation. Significantly fewer recipients in Group Bas experienced hepatitis B relapse than in Group Triple (2/131 vs. 13/137, p = 0.006).

CONCLUSIONS

A basiliximab-induced immunosuppressive protocol is a safe regimen that achieves similar survival without increasing the acute rejection rate for LT recipients with hepatitis B virus-related diseases. For patients with benign end-stage liver diseases, this regimen reduces medium-term mortality in high-risk patients. This regimen remarkably improves renal function in the first month after LT and is correlated with a decreased hepatitis B recurrence rate in adult patients after LT.

Lung transplantation: a treatment option in end-stage lung disease

BACKGROUND

Lung transplantation is the final treatment option in the end stage of certain lung diseases, once all possible conservative treatments have been exhausted. Depending on the indication for which lung transplantation is performed, it can improve the patient's quality of life (e.g., in emphysema) and/ or prolong life expectancy (e.g., in cystic fibrosis, pulmonary fibrosis, and pulmonary arterial hypertension). The main selection criteria for transplant candidates, aside from the underlying pulmonary or cardiopulmonary disease, are age, degree of mobility, nutritional and muscular condition, and concurrent extrapulmonary disease. The pool of willing organ donors is shrinking, and every sixth candidate for lung transplantation now dies while on the waiting list.

METHOD

We reviewed pertinent articles (up to October 2013) retrieved by a selective search in Medline and other German and international databases, including those of the International Society for Heart and Lung Transplantation (ISHLT), Eurotransplant, the German Institute for Applied Quality Promotion and Research in Health-Care (Institut für angewandte Qualitätsförderung und Forschung im Gesundheitswesen, AQUA-Institut), and the German Foundation for Organ Transplantation (Deutsche Stiftung Organtransplantation, DSO).

RESULTS

The short- and long-term results have markedly improved in recent years: the 1-year survival rate has risen from 70.9% to 82.9%, and the 5-year survival rate from 46.9% to 59.6%. The 90-day mortality is 10.0%. The postoperative complications include acute (3.4%) and chronic (29.0%) transplant rejection, infections (38.0%), transplant failure (24.7%), airway complications (15.0%), malignant tumors (15.0%), cardiovascular events (10.9%), and other secondary extrapulmonary diseases (29.8%). Bilateral lung transplantation is superior to unilateral transplantation (5-year survival rate 57.3% versus 47.4%).

CONCLUSION

Seamless integration of the various components of treatment will be essential for further improvements in outcome. In particular, the follow-up care of transplant recipients should always be provided in close cooperation with the transplant center.

Role of HLA-G as a predictive marker of low risk of chronic rejection in lung transplant recipients: a clinical prospective study

Human leukocyte antigen G (HLA-G) expression is thought to be associated with a tolerance state following solid organ transplantation. In a lung transplant (LTx) recipient cohort, we assessed (1) the role of HLA-G expression as a predictor of graft acceptance, and (2) the relationship between (i) graft and peripheral HLA-G expression, (ii) HLA-G expression and humoral immunity and (iii) HLA-G expression and lung microenvironment. We prospectively enrolled 63 LTx recipients (median follow-up 3.26 years [min: 0.44-max: 5.03]). At 3 and 12 months post-LTx, we analyzed graft HLA-G expression by immunohistochemistry, plasma soluble HLA-G (sHLA-G) level by enzyme-linked immunosorbent assay, bronchoalveolar lavage fluid (BALF) levels of cytokines involved in chronic lung allograft dysfunction (CLAD) and anti-HLA antibodies (Abs) in serum. In a time-dependent Cox model, lung HLA-G expression had a protective effect on CLAD occurrence (hazard ratio: 0.13 [0.03-0.58]; p = 0.008). The same results were found when computing 3-month and 1-year conditional freedom from CLAD (p = 0.03 and 0.04, respectively [log-rank test]). Presence of anti-HLA Abs was inversely associated with graft HLA-G expression (p = 0.02). Increased BALF level of transforming growth factor-β was associated with high plasma sHLA-G level (p = 0.02). In conclusion, early graft HLA-G expression in LTx recipients with a stable condition was associated with graft acceptance in the long term.

Lower incidence of CMV infection and acute rejections with valganciclovir prophylaxis in lung transplant recipients

Background

Cytomegalovirus (CMV) is the most common opportunistic infection following lung transplantation. CMV replication in the lung allograft is described as accelerating the development of bronchiolitis obliterans syndrome (BOS). Finding a strategy to prevent CMV infection is an important issue.

Methods

We performed a retrospective, single-centre study of 114 lung transplant recipients (LTRs) who underwent lung transplantation from January 2001 to December 2006. In a smaller cohort of 88 CMV seropositive (R+) LTRs, three months of valganciclovir prophylaxis (2004-2006) was compared to three months of oral ganciclovir (2001-2003) with respect to the incidence of CMV infection/disease, the severity of CMV disease, acute rejection, BOS-free 4 year survival and 4 year survival. In the whole group of 114 LTRs the impact of CMV infection on long-term survival (BOS free 4 year survival and 6 year survival) was assessed.

Results

For the cohort of 88 CMV seropositive LTRs, the incidence of CMV infection/disease at one year was lower in the valganciclovir group compared to the ganciclovir group (24% vs. 54%, p = 0.003). There was a tendency towards reduced CMV disease, from 33% to 20% and a significant lower incidence of asymptomatic CMV infection (22% vs. 4%, p = 0.005). A lower incidence of acute rejection was observed in the valganciclovir group. However, there was no significant difference between the two groups in BOS free 4 year survival and 4 year survival.

For the entire group of 114 LTRs, BOS-free 4 year survival for recipients with CMV disease was (32%, p = 0.005) and among those with asymptomatic CMV infection (36%, p = 0.061) as compared with patients without CMV infection (69%). Six year survival was lower among patients with CMV disease, (64%, p = 0.042) and asymptomatic CMV infection (55%, p = 0.018) than patients without CMV infection (84%).

Conclusions

A lower incidence of CMV infection/disease and acute rejections was observed with valganciclovir (3 months) when compared to oral ganciclovir (3 months). The long-term impact of CMV infection/disease was significant for BOS-free survival and survival.