Immune checkpoint inhibitor-associated myocarditis: a systematic analysis of case reports

Immune-Related Adverse Events Associated with Atezolizumab: Insights from Real-World Pharmacovigilance Data

The advancement of immuno-oncology has brought about a significant shift in cancer treatment methods, with antibody-based immune checkpoint inhibitors like atezolizumab leading the way in this regard. However, the use of this checkpoint blockade can result in immune-related adverse events due to increased T-cell activity. The full spectrum of these events is not yet completely understood. In this study, the United States FDA Adverse Event Reporting System (FAERS) was utilized to investigate immune-related adverse events linked with the use of atezolizumab. The study identified forty-nine immune-related adverse events that affected multiple organ systems, including cardiovascular, respiratory, hematologic, hepatic, renal, gastrointestinal, neurologic, musculoskeletal, dermatologic, endocrine, and systemic disorders. The strongest signals for relative risk occurred for immune-mediated encephalitis (RR = 93.443), autoimmune myocarditis (RR = 56.641), immune-mediated hepatitis (RR = 49.062), immune-mediated nephritis (RR = 40.947), and autoimmune arthritis (RR = 39.382). Despite the morbidity associated with these adverse events, emerging evidence suggests potential associations with improved survival outcomes. Overall, this report sheds light on the widespread immune-related adverse events that cause significant morbidity and mortality in patients with cancer being treated with atezolizumab and brings attention to them for the clinicians treating these patients.

Case report: Regression after low-dose glucocorticoid therapy in a case of acute immune myocarditis induced by anti-PD-1 therapy for NSCLC

Background

PD-1 inhibitors exhibit efficacy in managing unresectable/metastatic driver gene-negative NSCLC, albeit with potential immune-related adverse events (irAEs). Among these, immune checkpoint inhibitor-associated myocarditis (ICI-M) is rare yet lethal. This study presents the initial successful instance of ICI-M in a lung cancer patient, rescued by low-dose glucocorticoids post-deterioration during treatment.

Case summary

A 78-year-old male with a medical history of stage IV pT3N2M1 NSCLC underwent four cycles of palliative chemotherapy, resulting in stable disease (SD). Subsequent to declining further chemotherapy, the patient was transitioned to a targeted therapy regimen comprising Anlotinib in conjunction with PD-1 inhibitor immunotherapy. On the 26th day post-administration of the PD-1 inhibitor, the patient manifested Grade 2 immune-mediated myocarditis. Treatment encompassing 1mg/kg methylprednisolone combined with immunoglobulin shock therapy was initiated for 3 days, achieving symptomatic control. Nonetheless, upon tapering methylprednisolone dosage to 4-8mg/3-4d, the condition deteriorated, necessitating transfer to the intensive care unit. Methylprednisolone dosage was escalated to 80mg/day for 3 days, followed by gradual reduction by one-third to two-thirds weekly, culminating in the patient's safe discharge from the hospital.

Conclusion

Immune-related myocarditis linked to checkpoint inhibitors is often managed effectively with high-dose glucocorticoid therapy. However, in Asian populations, low-dose glucocorticoids are increasingly utilized for salvage therapy, yielding favorable outcomes and improving prognosis compared to European populations.

Immune Checkpoint Inhibitors-Associated Myocarditis: Diagnosis, Treatment and Current Status on Rechallenge

Immune checkpoint molecules like cytotoxic T-lymphocyte antigen 4 (CTLA-4), programmed cell death 1 (PD-1) or its ligand, programmed cell death ligand 1 (PD-L1), play a critical role in regulating the immune response, and immune checkpoint inhibitors (ICIs) targeting these checkpoints have shown clinical efficacy in cancer treatment; however, their use is associated with immune-related adverse events (irAEs), including cardiac complications. The prevalence of cardiac irAEs, particularly myocarditis, is relatively low, but they can become a severe and potentially life-threatening condition, usually occurring shortly after initiating ICI treatment; moreover, diagnosing ICI-related myocarditis can be challenging. Diagnostic tools include serum cardiac biomarkers, electrocardiography (ECG), echocardiography, cardiac magnetic resonance (CMR) and endomyocardial biopsy (EMB). The treatment of ICI-induced myocarditis involves high-dose corticosteroids, which have been shown to reduce the risk of major adverse cardiac events (MACE). In refractory cases, second-line immunosuppressive drugs may be considered, although their effectiveness is based on limited data. The mortality rates of ICI-induced myocarditis, particularly in severe cases, are high (38-46%). Therapy rechallenge after myocarditis is associated with a risk of recurrence and severe complications. The decision to rechallenge should be made on a case-by-case basis, involving a multidisciplinary team of cardiologists and oncologists. Further research and guidance are needed to optimize the management of cancer patients who have experienced such complications, evaluating the risks and benefits of therapy rechallenge. The purpose of this review is to summarize the available evidence on cardiovascular complications from ICI therapy, with a particular focus on myocarditis and, specifically, the rechallenge of immunotherapy after a cardiac adverse event.