Retrospective analysis of hospital admissions due to immune checkpoint inhibitor-induced immune-related adverse events (irAE)

Outcomes of High-Grade Immune Checkpoint Inhibitor Hepatitis in Hospitalized and Nonhospitalized Patients

BACKGROUND & AIMS

Guidelines recommend hospitalization for severe immune checkpoint inhibitor (ICI) hepatitis. We compared patient outcomes in the inpatient versus outpatient settings.

METHODS

We conducted a multicenter, retrospective cohort study of 294 ICI-treated patients who developed grade 3-4 ICI hepatitis. The primary outcome was time to alanine aminotransferase (ALT) normalization (≤40); secondary outcomes included time to ALT ≤100 U/L and time to death. To account for confounding by indication, inverse probability of treatment weighting was applied to perform Cox regression. A sensitivity analysis was performed excluding patients with grade 4 hepatitis.

RESULTS

One hundred and sixty-six patients (56.5%) were hospitalized for a median of 6 (interquartile range, 3-11) days. On inverse probability of treatment weighting Cox regression, hospitalization was not associated with time to ALT normalization (hazard ratio [HR], 1.11; 95% confidence interval [CI], 0.86-1.43; P = .436) or time to ALT ≤100 U/L (HR, 1.11; 95% CI, 0.86-1.43; P = .420). In the sensitivity analysis limited to patients with grade 3 hepatitis, hospitalization was also not associated with time to ALT normalization (HR, 1.11; 95% CI, 0.83-1.50; P = .474) or time to ALT ≤100 U/L (HR, 1.19; 95% CI, 0.90-1.58; P = .225). In a subgroup analysis of 152 patients with melanoma, hospitalization was not associated with reduced risk of all-cause death (HR, 0.93; 95% CI, 0.53-1.64; P = .798). Notably, despite their Common Terminology Criteria for Adverse Events classification of high-grade hepatitis, 94% of patients had "mild" liver injury based on International Drug-Induced Liver Injury Criteria.

CONCLUSIONS

Hospitalization of patients with high-grade ICI hepatitis was not associated with faster hepatitis resolution and did not affect mortality. Routine hospitalization may not be necessary in all patients with high-grade ICI hepatitis and Common Terminology Criteria for Adverse Events criteria may overestimate severity of liver injury.

Treatment patterns and survival outcomes of patients admitted to the intensive care unit due to immune-related adverse events of immune checkpoint inhibitors

INTRODUCTION

Severe immune-related adverse events (irAEs) due to immune checkpoint inhibitors (ICIs) can lead to admission to the intensive care unit (ICU). In this retrospective study, we determined the incidence, treatment patterns and survival outcomes of this patient population at a comprehensive cancer center.

METHODS

All patients admitted to the ICU due to irAEs from ICI treatment between January 2015 and July 2022 were included. Descriptive statistics were reported on patient characteristics and treatment patterns during hospital admission. Overall survival (OS) from the time of ICU discharge to death was estimated using the Kaplan-Meier method.

RESULTS

Over the study period, 5561 patients received at least one ICI administration, of which 32 patients (0.6%) were admitted to the ICU due to irAEs. Twenty patients were treated with anti-PD-1 plus anti-CTLA-4 treatment, whereas 12 patients were treated with ICI monotherapy. The type of irAEs were de novo diabetes-related ketoacidosis (n = 8), immune-related gastrointestinal toxicity (n = 8), myocarditis or myositis (n = 10), nephritis (n = 3), pneumonitis (n = 2), and myelitis (n = 1). The median duration of ICU admission was 3 days (interquartile range: 2-6 days). Three patients died during ICU admission. The median OS of the patients who were discharged from the ICU was 18 months (95% confidence interval, 5.0-NA).

CONCLUSION

The incidence of irAEs leading to ICU admission in patients treated with ICI was low in this study. ICU mortality due to irAEs was low and a subset of this patient population even had long-term survival.

Clinical guideline highlights for the hospitalist: Management of immune-related adverse events in patients treated with immune checkpoint inhibitor therapy

GUIDELINE TITLE

Management of Immune-Related Adverse Events in Patients Treated with Immune Checkpoint Inhibitor Therapy: ASCO Guideline Update RELEASE DATE: November 1, 2021 PRIOR VERSION(S): February 14, 2018 DEVELOPER: American Society of Clinical Oncology FUNDING SOURCE: American Society of Clinical Oncology TARGET POPULATION: Adult patients with cancer receiving treatment with immune checkpoint blockade inhibitors alone.

Out-of-hours admissions in patients treated with immune checkpoint inhibitors and their primary management with steroids

INTRODUCTION

The incidence of immune-related adverse events (irAEs) from immune checkpoint inhibitors (ICI) is well described. However, the impact on emergency care services is not. This study investigated the incidence of irAEs out-of-hours, and the management used to mitigate symptoms and side effects.

METHODS

This retrospective cohort study reviewed all emergency presentations triaged by the acute oncology team between December 2021 and June 2022, between 5 pm and 9 am. Patients were identified from triage audit sheets and remaining data points were retrieved from electronic health records. Inclusion criteria included all adult patients admitted on an ICI at one tertiary centre.

RESULTS

In 7 months, 970 patients called the acute oncology helpline 11% (n = 109) of patients were on an ICI treatment. After clinical review, 78% (n = 70) resulted in hospital admissions, with length of stay cumulating to 496 bed days. 56% (n = 39) of patients delayed reporting symptoms, ranging between 12 hours and 10 days from symptom onset to seeking support. 49% (n = 34) patients received steroids to manage suspected irAEs. Dexamethasone was the most common steroid used in 71% (n = 24) of patients, and variation was found in prescribed doses.

CONCLUSIONS

These results underline the urgent need to address patient and staff education on adverse effects related to ICI. Patients require a comprehensive understanding of the symptoms and importance of prompt reporting. Staff education on recognition and treatment management is needed to reduce variation in practice. Further research is needed to identify barriers in symptom reporting and focus on realtime reporting to reduce the out-of-hours burden on services.

Machine Learning Models Using Routinely Collected Clinical Data Offer Robust and Interpretable Predictions of 90-Day Unplanned Acute Care Use for Cancer Immunotherapy Patients

PURPOSE

Clinical management of patients receiving immune checkpoint inhibitors (ICIs) could be informed using accurate predictive tools to identify patients at risk of short-term acute care utilization (ACU). We used routinely collected data to develop and assess machine learning (ML) algorithms to predict unplanned ACU within 90 days of ICI treatment initiation.

METHODS

We used aggregated electronic health record data from 7,960 patients receiving ICI treatments to train and assess eight ML algorithms. We developed the models using pre-SARS-COV-19 COVID-19 data generated between January 2016 and February 2020. We validated our algorithms using data collected between March 2020 and June 2022 (peri-COVID-19 sample). We assessed performance using area under the receiver operating characteristic curves (AUROC), sensitivity, specificity, and calibration plots. We derived intuitive explanations of predictions using variable importance and Shapley additive explanation analyses. We assessed the marginal performance of ML models compared with that of univariate and multivariate logistic regression (LR) models.

RESULTS

Most algorithms significantly outperformed the univariate and multivariate LR models. The extreme gradient boosting trees (XGBT) algorithm demonstrated the best overall performance (AUROC, 0.70; sensitivity, 0.53; specificity, 0.74) on the peri-COVID-19 sample. The algorithm performance was stable across both pre- and peri-COVID-19 samples, as well as ICI regimen and cancer groups. Type of ICI agents, oxygen saturation, diastolic blood pressure, albumin level, platelet count, immature granulocytes, absolute monocyte, chloride level, red cell distribution width, and alcohol intake were the top 10 key predictors used by the XGBT algorithm.

CONCLUSION

Machine learning algorithms trained using routinely collected data outperformed traditional statistical models when predicting 90-day ACU. The XGBT algorithm has the potential to identify high-ACU risk patients and enable preventive interventions to avoid ACU.

Exploring the educational needs for severe immune-related adverse events of PD-1/PD-L1 inhibitors in advanced lung cancer : A single-center observational study

Objective

With the expanded use of immunotherapy in medical oncology, effective patient education regarding immune-related adverse events (irAEs) is crucial for oncology nursing. Therefore, this study aimed to identify educational needs for preventing unscheduled hospitalizations due to severe irAEs.

Methods

We retrospectively reviewed the medical records of 159 consecutive patients with lung cancer who received programmed cell death-1 (PD-1)/programmed death-ligand 1 (PD-L1) inhibitors in 2020. We evaluated the frequency, severity, and unscheduled hospitalization due to irAEs based on the PD-1/PD-L1 inhibitor use. Educational needs were assessed based on initial symptoms, reporters, telephone consultation, and the time lag between symptom onset and hospital visit.

Results

Among 159 patients evaluable for irAEs, 73 (45.9%) experienced 91 irAEs during the study period. Seventeen patients (10.7%) required unscheduled hospitalization due to severe irAEs after a median duration of 4.1 days from symptom onset, and 52.9% visited hospitals after telephone consultations from caregivers. Pneumonitis (10 events) was the most frequent irAE requiring hospitalization, followed by adrenal insufficiency (three events). The type and severity of irAEs varied based on PD-1/PD-L1 inhibitor use.

Conclusions

The frequency of severe irAEs requiring hospitalization was high in patients who received PD-1/PD-L1 inhibitors for advanced lung cancer. The early detection of severe irAEs may be possible through education focusing on common irAEs that are potentially severe. Patients and caregivers should be aware of the importance of reporting slight changes in symptoms after PD-1/PD-L1 therapy initiation in a timely manner. Healthcare professionals need to acknowledge common irAEs and be qualified to implement systematic telephone triage of irAEs.

Immune-related adverse events and immune checkpoint inhibitor tolerance on rechallenge in patients with irAEs: a single-center experience

BACKGROUND

Given the widespread use of immune checkpoint inhibitors (ICIs), newer immune related adverse events (irAEs) have come to light, including flare-ups of preexisting autoimmune disorders (AIDs) and delayed immune-related events. We aimed to identify the frequency and severity of new IRAEs, including AID flares in cancer patients treated with ICIs at our institution. We also studied the tolerability of ICIs upon rechallenge in patients with irAEs and hospital admissions due to irAEs in a community setting in rural Maine.

METHODS

We conducted a retrospective chart review analysis of all patients with cancer who received anti-PDL1/PDL1 inhibitors nivolumab, pembrolizumab, atezolizumab, and durvalumab at our tertiary care center from November 2015 to March 2019. Demographic data, cancer type and stage, irAEs, hospital admissions due to irAEs, and drug treatment information was extracted.

RESULTS

We included 465 patients who received ICIs, 115 (out of 465 25%) developed new irAEs. Preexisting AID were identified in 47 (out of 465) (10%), AID flares were observed in 12 patients (25% of 47). 17 (out of 47 36%) were on immunosuppression for underlying AID, 5 (out of 17, 29%) developed flares. Overall, 148 (32% of 465) irAEs occurred, as some patients had multiple toxicities. Majority were treated for Lung cancer (63%), followed by melanoma and genitourinary cancers. Due to irAE severity, treatment was permanently discontinued in 15% (out of 465) patients. Hospital admissions due to irAEs were required for 34 patients (7.3% of 465). ICI rechallenge was performed in 27 patients (6% of 465), and majority tolerated well.

CONCLUSION

Our study shows that ICIs were generally well tolerated and can be used safely even in patients with preexisting AIDs; it is encouraging to see majority tolerated rechallenge with ICIs well.