Incidence and risk factors of acute kidney injury in cancer patients treated with immune checkpoint inhibitors: a systematic review and meta-analysis

Disproportionality Analysis of Renal Adverse Events Associated with a Combination of Immune Checkpoint Inhibitors and Acid-Suppressing Agents-A Pharmacovigilance Study Based on the FAERS Database

Background/Objectives: The nephrotoxicity of immune checkpoint inhibitors (ICIs) combined with proton pump inhibitors (PPIs) has been recognized but lacks a comprehensive analysis. We conducted an in-depth investigation of renal adverse events (rAEs) associated with ICIs and different acid-suppressing agents (ASAs)-including PPIs, histamine-2 receptor antagonists (H2RAs), and potassium-competitive acid blockers (P-CABs)-using real-world data from the FDA's Adverse Event Reporting System (FAERS). Methods: We analyzed rAE reports from the FAERS database covering Q1 2004 to Q1 2023. Disproportionality analysis was conducted to identify rAEs associated with ICI or ASA monotherapy or combination therapy. Univariate logistic regression was employed to explore influencing factors. Results: No eligible rAE reports were retrieved for H2RAs and P-CABs. However, 6,775 reports in the ICI group, 54,055 reports in the PPI group, and 210 reports in the ICI-PPI combination therapy group were included in the final analysis. In PPI-ICI combination settings, tubulointerstitial nephritis had the highest reporting frequency and signal intensity; the overall risk of rAEs was significantly elevated compared to ICI or PPI monotherapy, with reporting odds ratios of 14. 65 (95% confidence interval [CI] 12.93-16.58) and 3.24 (95% CI 2.87-3.66), respectively; the median onset time was shortest at 21 days (interquartile range 5.5-135); and PD-1 monotherapy, omeprazole, and rabeprazole were associated with higher rAE risks. Conclusions: Our findings confirm that the combination of PPIs (but not other ASAs) with ICIs further increases the risk of various acute and chronic rAEs. Healthcare providers should exercise caution when managing patients on these therapies.

The differentiation and intervention strategies for acute kidney injury after or induced by immune checkpoint inhibitors

With the increasing popularity of immune checkpoint inhibitors (ICIs) in tumor treatment, the incidence of immune-related adverse events (irAEs), including acute kidney injury (AKI), is on the rise. Renal biopsy serves as the gold standard for determining the true etiology of AKI following ICIs administration; however, due to potential risks and associated losses with this procedure, comprehensive analysis of physiological data and predictive models are gradually being incorporated into clinical practice to differentiate AKI etiologies. These include criteria such as a ≥ 100% increase in serum creatinine (Scr) from baseline or a 50% increase accompanied by other pathological manifestations, renal replacement therapy (RRT), or absence of any other reasonable cause. Currently, cessation of ICIs and steroid therapy represent commonly employed treatment approaches; nevertheless, these strategies have inherent side effects and may not be feasible for certain patient populations, such as those with diabetes, posing challenges for clinicians. Recent studies have demonstrated that rituximab, mycophenolate mofetil (MMF), and infliximab can potentially replace steroid therapy in managing ICIs-induced AKI (ICIs-AKI), offering a novel therapeutic perspective. This review provides an overview of non-invasive methods for distinguishing between AKI following ICIs use and ICIs-AKI while discussing strategies for treating ICIs-AKI.

Acute Kidney Injury Associated with Novel Anticancer Therapies: Immunotherapy

The landscape of cancer survival has been positively affected by the introduction and dissemination of immunotherapy with the wide usage of immune checkpoint inhibitors and chimeric antigen receptors cell therapies. The success of these novel therapies can, however, be limited to a certain extent by systemic inflammatory toxicities affecting, directly or indirectly, the kidney. In the case of immune checkpoint inhibitors, severe acute interstitial nephritis is the main adverse event and can lead to permanent discontinuation of the therapy. In turn, chimeric antigen receptor cell therapy can cause cytokine release syndrome and immune effector cell-associated hemophagocytic lympho-histiocytosis, with kidney damage through various mechanisms, and be life threatening. Prompt diagnosis and management of these entities is essential to preserve kidney function and ensure the best possible kidney and overall outcomes to patients with cancer.

Nephrotoxicity of Immune Checkpoint Inhibitors in Single and Combination Therapy-A Systematic and Critical Review

Background/Objectives: Immune checkpoint inhibitors (ICIs) have generated a revolutionary approach in the treatment of cancer, but their effectiveness has been compromised by immune-related adverse events, including renal damage. Although rare, these effects are relevant because they have been related to poor patient prognoses. The objective of this review was to estimate the current incidence of nephrotoxicity in patients treated with single and double ICI therapies. Methods: A total of 1283 potential articles were identified, which were reduced to 50 after applying the exclusion and inclusion criteria. Results: This study reveals the increase in acute kidney injury associated with these drugs in the last decade and shows that, interestingly, combined therapies with ICIs does not lead to an increase in kidney damage compared with anti-CTLA-4. It also suggests that kidney damage could be underdiagnosed when it comes to interstitial nephritis, because definitive evidence requires a renal biopsy. Conclusions: In perspective, these conclusions could guide clinicians in making decisions for therapy personalization and highlight the need to search for new diagnostic systems that are more sensitive and specific to the type of damage and could replace the biopsy.

Amikacin Dosing Adjustment in Critically Ill Oncologic Patients: A Study with Real-World Patients, PBPK Analysis, and Digital Twins

Background/Objectives: Guidelines recommend adjusting amikacin dosing based on patients' renal function. Nevertheless, for critically ill cancer patients, the renal function equations based on serum creatinine levels have low or no correlation with amikacin clearance. Considering this, using real-world data, we built an amikacin PBPK model to predict amikacin plasma concentrations in critically ill oncologic patients stratified by renal impairment levels. Further, the model was applied for dose stratification and individualization (digital twin strategy) in this population. Methods: In the Therapeutic Drug Monitoring (TDM) study, 368 amikacin pharmacokinetic analyses from 184 critically ill cancer patients were enrolled in three cohorts. A full-body PBPK model was developed using PK-Sim v. 11.3. Results: The final PBPK model accounted for two groups of critically ill cancer patients with mild (creatinine clearance; CLcr ≥ 60 mL/min) or severe (CLcr < 60 mL/min) renal dysfunction. In the dose stratification strategy, at the 7th dose, cancer patients with CLcr ≥ 60 mL/min under regimens 20 mg/kg (q24h); 25 mg/kg (q24h); 25 mg/kg (q48h); and 30 mg/kg (q72h) have probability of ≥69% of the patients achieving the efficacy target (AUC/MIC > 80, MIC of 4 mg/L), while cancer patients with CLcr < 60 mL/min under regimens 7.5 mg/kg (q24h); 15 mg/kg (q24h); 15 mg/kg (q48h); and 20 mg/kg (q36h) have ≥90% probability of achieving the same efficacy target. Conclusions: Our MIPD approach demonstrates potential in optimizing amikacin dosing for critically ill cancer patients. However, it does not eliminate the need for TDM due to unexplained variability still not accounted for by the PBPK model.

Clinical outcomes after immune checkpoint inhibitor-associated acute kidney injury: a cohort study

OBJECTIVES

Immune checkpoint inhibitors (ICPi) have significantly improved survival for patients with advanced cancers. However, the occurrence of ICPi-associated acute kidney injury (AKI) and its clinical impact remains unclear. This study evaluates the effects of ICPi-associated AKI (ICPi-AKI) on mortality, kidney and cardiovascular outcomes in patients undergoing ICPi treatments.

DESIGN

This multicentre retrospective cohort study with propensity score matching to balance baseline characteristics. The International Classification of Diseases, 10th Revision codes were used to identify individuals with cancer and treated with ICPi concurrently. Kaplan-Meier analyses coupled with log-rank tests were conducted to estimate the survival probabilities.

SETTING

Data were sourced from the TriNetX database spanning records from 25 March 2011 to 5 April 2024.

PARTICIPANTS

Patients with cancer aged ≥18 years treated with ICPi with or without AKI occurrence.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcome was all-cause mortality, and secondary outcomes included major adverse kidney events (MAKE), major adverse cardiovascular events (MACE), the composite of MAKE or MACE with death, and end-stage renal disease.

RESULTS

The study identified 926 patients with cancer who developed ICPi-AKI (mean age, 67.1±11.8 years; 57.4% men). The control group consisted of 48 147 patients treated with ICPi but did not develop AKI (mean age, 65.3±13.1 years; 53.7% men). After matching, the ICPi-AKI group exhibited a higher risk of all-cause mortality (HR=1.27; 95% CI 1.02 to 1.61), MAKE (HR=3.83; 95% CI 1.72 to 8.40), MACE (HR=1.35; 95% CI 1.03 to 1.75)) compared with the non-ICPi-AKI group. Subgroup analyses confirmed these findings across various patient's characteristics.

CONCLUSION

Individuals with ICPi-AKI are associated with an increased risk of all-cause mortality, MAKE and MACE. Enhancing awareness and timely intervention for ICPi-AKI are crucial for improving prognosis and reducing complications among patients with cancer.

Pharmacotherapy considerations in patients who develop acute kidney injury during anti-cancer therapy

INTRODUCTION

Acute kidney injury (AKI) frequently develops in patients receiving cancer therapy and requires a wide differential diagnosis due to possible role of unique cancer and drug-related factors, in addition to common pre- and post-renal causes. Rapid development of new molecular targeted anti-cancer drugs and immunotherapies has opened unprecedented possibilities of treatment at the price of an increased spectrum of renal side effects.

AREAS COVERED

The present review aims at providing a state-of-the-art picture of AKI in cancer patient (PubMed and Embase libraries were searched from inception to January 2024), with a focus on differential diagnosis and management of diverse clinical settings. Reports of parenchymal AKI due to glomerular, microvascular, tubular and interstitial damage have been constantly increasing. Complex electrolyte and acid-base disorders can coexist. The role of renal biopsy and possible therapeutic approaches are also discussed.

EXPERT OPINION

Onconephrology has become an important subspecialty of clinical nephrology, requiring constantly updated skills and a high degree of interdisciplinary integration to tackle diagnostic challenges and even therapeutic and ethical dilemmas. Integrated onconephrological guidelines and availability of biomarkers may provide new tools for management of this unique type of patients in the near future.

Metastatic Melanoma Treatment in Special Populations

ABSTRACT

This review outlines the most up-to-date metastatic melanoma treatment recommendations and relevant risks for patients with solid organ transplants, patients with renal dysfunction, and patients with preexisting autoimmune conditions. These specific treatment populations were excluded from the original clinical trials, which studied immune checkpoint inhibitors and BRAF/MEK inhibitors in the advanced melanoma setting. We have synthesized the current body of literature, mainly case series and retrospective analyses, to reflect the evidence for the treatment of these special patient populations at present.

Immune checkpoint inhibitors and acute kidney injury

As a new type of anti-tumor immunotherapy, immune checkpoint inhibitors (ICIs) have improved the prognosis of multiple malignancies. However, renal complications are becoming more frequent. Nephrotoxicity often manifests as acute kidney injury (AKI), and the most common histopathological type is acute tubulointerstitial nephritis (ATIN). Based on previous studies of the incidence and potential risk factors for nephrotoxicity, in this review, we describe the mechanism of AKI after ICIs treatment, summarize the incidence, risk factors, and outcomes of AKI, and discuss the diagnosis and management of immune checkpoint inhibitors-associated acute kidney injury (ICI-AKI). In addition, we review the current status of ICIs rechallenge and the therapeutic strategies of ICIs applied in kidney transplant recipients. Finally, we emphasize the importance of collaboration between nephrologists and oncologists to guide the treatment of ICIs and the management of renal complications.

Severe Acute Kidney Injury in Hospitalized Cancer Patients: Epidemiology and Predictive Model of Renal Replacement Therapy and In-Hospital Mortality

BACKGROUND

Acute kidney injury (AKI) is a common complication among cancer patients, often leading to longer hospital stays, discontinuation of cancer treatment, and a poor prognosis. This study aims to provide insight into the incidence of severe AKI in this population and identify the risk factors associated with renal replacement therapy (RRT) and in-hospital mortality.

METHODS

This retrospective cohort study included 3201 patients with cancer and severe AKI admitted to a Comprehensive Cancer Center between January 1995 and July 2023. Severe AKI was defined according to the KDIGO guidelines as grade ≥ 2 AKI with nephrological in-hospital follow-up. Data were analyzed in two timelines: Period A (1995-2010) and Period B (2011-2023).

RESULTS

A total of 3201 patients (1% of all hospitalized cases) were included, with a mean age of 62.5 ± 17.2 years. Solid tumors represented 75% of all neoplasms, showing an increasing tendency, while hematological cancer decreased. Obstructive AKI declined, whereas the incidence of sepsis-associated, prerenal, and drug-induced AKI increased. Overall, 20% of patients required RRT, and 26.4% died during hospitalization. A predictive model for RRT (AUC 0.833 [95% CI 0.817-0.848]) identified sepsis and hematological cancer as risk factors and prerenal and obstructive AKI as protective factors. A similar model for overall in-hospital mortality (AUC 0.731 [95% CI 0.71-0.752]) revealed invasive mechanical ventilation (IMV), sepsis, and RRT as risk factors and obstructive AKI as a protective factor. The model for hemato-oncological patients' mortality (AUC 0.832 [95% CI 0.803-0.861]) included IMV, sepsis, hematopoietic stem cell transplantation, and drug-induced AKI. Mortality risk point score models were derived from these analyses.

CONCLUSIONS

This study addresses the demographic and clinical features of cancer patients with severe AKI. The development of predictive models for RRT and in-hospital mortality, along with risk point scores, may play a role in the management of this population.

Proton pump inhibitors and adverse kidney outcomes during immune checkpoint blockade: time to sound the alarm?

Immune checkpoint inhibitors (ICIs) have significantly altered the treatment landscape for cancer in the last decade. However, their benefits are often offset by therapy-limiting immune-related adverse events (irAEs). Acute interstitial nephritis (AIN) is the most common renal irAE, but the exact mechanisms underlying its development are poorly understood. ICI-induced immune activation against drug-derived antigens, leading to an inflammatory response within the kidney interstitium, has been postulated, evidenced by current observations of a higher incidence of ICI-associated AIN in patients receiving AIN-inducing drugs such as proton pump inhibitors (PPIs). The role of PPIs in this specific context has garnered significant attention, given their ubiquitous use and sometimes misuse. In this issue of CKJ Miao et al. summarise and synthesize the best available evidence to clarify the interactions of PPIs with ICIs in the development of AIN and other adverse kidney outcomes. The sum of evidence provided appear to implicate PPIs in the development of clinically significant short- and long-term kidney-related adverse effects in patients on immune checkpoint blockade, although causality cannot be proven. In this editorial we discuss the key practical implications of these findings and emphasize the need for further quality studies to delineate the true relationship of ICIs and PPIs in the development of AIN.