Combined low-dose everolimus and low-dose tacrolimus after Alemtuzumab induction therapy: a randomized prospective trial in lung transplantation

Conventional and Novel Approaches to Immunosuppression in Lung Transplantation

Most therapeutic advances in immunosuppression have occurred over the past few decades. Although modern strategies have been effective in reducing acute cellular rejection, excess immunosuppression comes at the price of toxicity, opportunistic infection, and malignancy. As our understanding of the immune system and allograft rejection becomes more nuanced, there is an opportunity to evolve immunosuppression protocols to optimize longer term outcomes while mitigating the deleterious effects of traditional protocols.

Risk of melanoma and nonmelanoma skin cancer with immunosuppressants, part I: Calcineurin inhibitors, thiopurines, IMDH inhibitors, mTOR inhibitors, and corticosteroids

Immunosuppression is a well-documented risk factor for skin cancer, as exemplified by the 65- to 250-fold higher squamous cell carcinoma risk, 10-fold higher basal cell carcinoma risk, and 0 to 8-fold higher melanoma risk in solid organ transplant recipients (SOTRs) receiving potent, prolonged courses of immunosuppressive therapies. Numerous immune system components have been shown to either suppress or promote tumor growth, and immunosuppressive drugs may have additional effects on proliferative pathways independent of the immune system. Thus, evaluation of the specific regimen by the dermatologist is key for assessing skin cancer risk in each patient. In the present manuscript, the immune-mediated mechanisms of skin cancer development and regression are first reviewed. Next, a synthesis of the evidence shows the differing effects of immunosuppressive agents commonly used in SOTRs on melanoma and nonmelanoma skin cancer risk. These include systemic calcineurin inhibitors, thiopurines, IMDH (inosine monophosphate dehydrogenase) inhibitors, mTOR (mammalian target of rapamycin) inhibitors, and systemic corticosteroids. Finally, recommendations for skin cancer screening in SOTRs are discussed. We further offer recommendations for select nontransplant patients who may benefit from routine skin cancer screening due to risks associated with specific immunosuppressant exposure, and we propose evidence-based strategies for minimizing high-risk immunosuppressant use in clinical practice.

Rescue Everolimus Post Lung Transplantation is Not Associated With an Increased Incidence of CLAD or CLAD-Related Mortality

Everolimus (EVE) has been used as a calcineurin inhibitor (CNI) minimization/ elimination agent or to augment immunosuppression in lung transplant recipients (LTR) with CNI-induced nephrotoxicity or neurotoxicity. The long-term evidence for survival and progression to chronic lung allograft dysfunction (CLAD) is lacking. The primary aim was to compare survival outcomes of LTR starting EVE-based immunosuppression with those remaining on CNI-based regimens. The secondary outcomes being time to CLAD, incidence of CLAD and the emergence of obstructive (BOS) or restrictive (RAS) phenotypes. Single center retrospective study of 91 LTR starting EVE-based immunosuppression matched 1:1 with LTR remaining on CNI-based immunosuppression. On multivariate analysis, compared to those remaining on CNI-based immunosuppression, starting EVE was not associated with poorer survival [HR 1.04, 95% CI: 0.67-1.61, p = 0.853], or a statistically significant faster time to CLAD [HR 1.34, 95% CI: 0.87-2.04, p = 0.182]. There was no difference in the emergence of CLAD (EVE, [n = 57, 62.6%] vs. CNI-based [n = 52, 57.1%], p = 0.41), or the incidence of BOS (p = 0.60) or RAS (p = 0.16) between the two groups. Introduction of EVE-based immunosuppression does not increase the risk of death or accelerate the progression to CLAD compared to CNI-based immunosuppression.

Everolimus Use in Lung Transplant Recipients

BACKGROUND

Most lung transplantation centers prefer triple immunosuppressive therapy with tacrolimus, mycophenolate mofetil, and corticosteroids. However, to prevent complications and comorbidities caused by tacrolimus, replacing the drug with everolimus has been considered.

METHODS

This is a retrospective observational study investigating everolimus switch for different reasons. The population was divided into 3 groups: chronic lung allograft dysfunction (CLAD), kidney impairment, and malignant neoplasm groups. We investigated whether we achieved the goal of the switch and the frequency of rejection, cytomegalovirus and fungal infections, and everolimus adverse effects.

RESULTS

Nineteen patients received everolimus therapy, and 5 of these were for CLAD, 7 for tacrolimus nephrotoxicity, and 7 for explant/de novo malignant neoplasm. The patients were followed up for a mean (SD) of 30 (16.7) months under the therapy. The number of acute cellular rejection, cytomegalovirus infection, and aspergillosis infection cases before switch were 7, 13, and 2, respectively, and 7, 2, and 3 after that. The mean values of creatinine and estimated glomerular filtration rate of the whole population after the switch improved with no statistical significance, whereas it was significant in tacrolimus nephrotoxicity group. Three patients in the CLAD group remained stable after switching, whereas 2 progressed. Only 1 of the 7 patients with malignant neoplasms had a recurrence during 31.1 (16.5) months of median follow-up. Eleven cases of everolimus adverse effects occurred in 9 patients (47.3%), with 2 (10.5%) withdrawal events. Kidney impairment (P = .02) and age (P = .05) stood out as significant risk factors for drug adverse effects.

CONCLUSIONS

After lung transplant, everolimus can be a safe alternative for immunosuppression with acceptable adverse effects.

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.