Induction Strategies in Lung Transplantation: Alemtuzumab vs. Basiliximab a Single-Center Experience

Basiliximab induction immunosuppression and lung transplant outcomes: Propensity analysis in a multicenter cohort

BACKGROUND

Basiliximab induction immunosuppression is increasingly employed in lung transplant recipients despite limited prospective evidence to support its use in this population. We sought to determine the relationship between basiliximab induction and development of acute rejection, chronic lung allograft dysfunction, and other clinically relevant outcomes in a multicenter lung transplant cohort with variable induction practice patterns.

METHODS

We applied propensity-based statistical methods to rigorous, prospectively collected longitudinal data from 768 newly transplanted adult lung recipients at 5 North American centers (368 who received basiliximab induction immunosuppression and 400 who received no induction immunosuppression). Treatment effects were estimated using outcome-specific propensity score regression models, weighted by the outcome-specific overlap weights, and stratified by center strata.

RESULTS

Basiliximab induction immunosuppression was associated with a significant reduction in any grade acute rejection (HR 0.65, 95% CI 0.46-0.92; p=0.015), organizing pneumonia histology (HR 0.38, 95% CI 0.16-0.90; p=0.028), acute lung injury histology (HR 0.28, 95% CI 0.13-0.61; p=0.001), and development of class II donor specific antibodies (HR 0.51, 95% CI 0.27-0.95; p=0.034) within the first posttransplant year. However, there was no significant association between basiliximab and development of chronic lung allograft dysfunction, mortality, or graft loss. For select infections during the first posttransplant year, there was no evidence of a difference in risk between patients who did versus did not receive basiliximab.

CONCLUSIONS

Basiliximab induction immunosuppression is associated with a significant reduction in early posttransplant cellular and humoral immune events and lung injury histologies but not chronic lung allograft dysfunction or mortality.

Inefficiency Rates of Biological Immunosuppressive Induction Agents Used in Organ Transplantation: A Pharmacovigilance Study

Effective immunosuppressant pharmacotherapy is essential for successful organ transplantation. Background/Objectives: Generally, induction therapy includes basiliximab (BAS) or anti-thymocyte globulin (THY). However, other biological molecules have been used to accelerate firm immunosuppression. A reduced effectiveness of these induction agents increases the risk of graft rejection. This study aims to evaluate the ineffectiveness rate of biological molecules based on spontaneous reports uploaded to the EudraVigilance database. Methods: Specific topics related to the safety profiles of alemtuzumab, BAS, belatacept, and THY were analyzed. A total of 23 preferred terms describing drug resistance, drug ineffectiveness, and transplant rejection were used as the inclusion criteria. Descriptive and disproportionality analyses were performed. Results: Regarding the four molecules, 18,564 safety reports were communicated, with n = 5089 (27.4%) for THY and n = 3469 (18.7%) for BAS. Most adverse drug reactions (ADRs) for THY, BAS, and belatacept affected the adult male population. As expected, the majority of the ADRs were linked to infections, followed by general disorders. BAS presented higher probabilities of drug resistance and transplant rejection being reported among the four molecules. A higher probability of reporting drug ineffectiveness was noted for THY than for the other molecules. Conclusions: All the molecules showed small frequencies regarding resistance. As expected, transplant rejection was more frequently reported for all molecules (especially for BAS), accompanied by a notable variability in reporting frequencies. However, a causal relationship between the reported adverse reactions and drug efficacy cannot be established based on the present results. Further real-world evidence studies will enhance our understanding of the safety and efficacy of these drugs in transplant patients.

The role of induction therapy in lung transplantation

Induction immunosuppression in solid organ transplantation involves a short course of potent immunosuppression in the perioperative period, with the goal of preventing early acute rejection and delaying initiation or reducing the dose of calcineurin inhibitors to minimize kidney injury. The use of induction immunosuppression in lung transplantation has increased over time, with over 80% of adult lung transplant recipients receiving some form of induction therapy. Currently, more than 70% of lung transplant recipients receive induction with an interleukin-2 receptor antagonist, and basiliximab is the most used agent. Despite this now common practice, the evidence to support and guide induction immunosuppression following lung transplantation is limited, making the use of induction somewhat controversial. Here, we review the available literature addressing the use of induction immunosuppression in lung transplant recipients.

Small airway brush gene expression predicts chronic lung allograft dysfunction and mortality

BACKGROUND

Chronic lung allograft dysfunction (CLAD) limits survival following lung transplant, but substantial lung damage occurs before diagnosis by traditional methods. We hypothesized that small airway gene expression patterns could identify CLAD risk before spirometric diagnosis and predict subsequent graft failure.

METHODS

Candidate genes from 4 rejection-associated transcript sets were assessed for associations with CLAD or graft failure in a derivation cohort of 156 small airway brushes from 45 CLAD cases and 37 time-matched controls with >1-year stable lung function. Candidate genes not associated with CLAD and time to graft failure were excluded, yielding the Airway Inflammation 2 (AI2) gene set. Area under the receiver operating curve (AUC) for CLAD and competing risks of death or graft failure were assessed in an independent validation cohort of 37 CLAD cases and 37 controls.

RESULTS

Thirty-two candidate genes were associated with CLAD and graft failure, comprising the AI2 score, which clustered into 3 subcomponents. The AI2 score identified CLAD before its onset, in early and late post-CLAD brushes, as well as in the validation cohort (AUC 0.69-0.88). The AI2 score association with CLAD was independent of positive microbiology, CLAD stage, or CLAD subtype. However, transcripts most associated with CLAD evolved over time from CLAD onset. The AI2 score predicted time to graft failure and retransplant-free survival in both cohorts (p ≤ 0.03).

CONCLUSIONS

This airway inflammation gene score is associated with CLAD development, graft failure, and death. Future studies defining the molecular heterogeneity of airway inflammation could lead to endotype-targeted therapies.

Donor and recipient risk factors for the development of primary graft dysfunction following lung transplantation

Primary Graft Dysfunction (PGD) is a major cause of both short-term and long-term morbidity and mortality following lung transplantation. Various donor, recipient, and technical risk factors have been previously identified as being associated with the development of PGD. Here, we present a comprehensive review of the current literature as it pertains to PGD following lung transplantation, as well as discussing current strategies to mitigate PGD and future directions. We will pay special attention to recent advances in lung transplantation such as ex-vivo lung perfusion, thoracoabdominal normothermic regional perfusion, and up-to-date literature published in the interim since the 2016 ISHLT consensus statement on PGD and the COVID-19 pandemic.

Risk Factors and Outcomes of Postoperative Hepatic Dysfunction After Lung Transplantation

BACKGROUND

Hepatic dysfunction is a morbid complication of lung transplantation. Little is known about risk factors for postoperative hepatic dysfunction or its impact on survival after lung transplantation.

METHODS

This retrospective analysis of 1406 adult lung transplant recipients was performed at the University of Pittsburgh Medical Center in Pittsburgh, Pennsylvania between January 1, 2007 and December 1, 2019. Patients were excluded for redo lung transplantation, concomitant cardiac surgery, or concurrent solid organ transplantation. Postoperative liver dysfunction was classified as either ischemic liver injury or nonischemic dysfunction (transaminitis, hyperbilirubinemia).

RESULTS

Among the 1155 primary lung transplant recipients included, postoperative hepatic dysfunction developed in 96 (8.3%) after lung transplantation. A history of liver disease was the greatest predictor of postoperative hepatic dysfunction (odds ratio, 6.19; CI, 2.13-17.4; P < .001). Patients with postoperative hepatic dysfunction had a greater need for intraoperative blood products (ischemic, 12 U [range, 6-21 U]; nonischemic, 10 U [range, 4-28 U]; vs none, 4 U [range, 1-12 U]; P < .001) and an increased need for postoperative circulatory support (ischemic, 16 [76%]; nonischemic, 25 [33%]; none, 117 [11%]; P < .001). Both ischemic liver injury and nonischemic dysfunction were associated with diminished 1-, 3-, and 5-year term survival (ischemic, 27.5%, 16.5%, and 0%, respectively; nonischemic, 60%, 49.6%, and 46.9%, respectively; none, 87.3%, 72.3%, and 59.5%, respectively; P < .001).

CONCLUSIONS

Hepatic dysfunction after lung transplantation is associated with significant morbidity and mortality. A history of liver disease was the best positive predictor for postoperative dysfunction. Additional studies are necessary to identify the best treatment algorithm to avoid hepatic dysfunction more effectively in the postoperative setting after lung transplantation.