Rituximab for severe immune checkpoint inhibitor-related adverse events: a multicenter case series

Area of Science:

• Oncology
• Immunology
• Pharmacology

Background:

• Immune checkpoint inhibitors (ICIs) can cause severe, life-threatening immune-related adverse events (irAEs).
• Standard immunosuppressive therapies may be ineffective for refractory irAEs.
• Rituximab is a potential treatment, but clinical evidence is limited.

Purpose of the Study:

• To evaluate the efficacy and safety of rituximab for severe immune-related adverse events (irAEs) induced by immune checkpoint inhibitors (ICIs).
• To assess rituximab as a second- or third-line therapy for refractory irAEs.
• To analyze outcomes in patients treated with rituximab for ICI-induced irAEs.

Main Methods:

• Retrospective multicenter study of patients treated with rituximab for severe ICI-related irAEs (2018-2023).
• Data collected included clinical characteristics, irAE type/severity, prior treatments, outcomes, and oncologic status.
• Overall survival was estimated from rituximab initiation.

Main Results:

• Eighteen patients (median age 66) with grade 3-4 irAEs (neurological, myositis/myocarditis, ILD) refractory to standard therapy were included.
• Rituximab, used as second- or third-line treatment, led to clinical improvement in 83% of patients, with 39% achieving complete resolution.
• After median follow-up of 9.7 months, 39% of patients died, but only 17% succumbed directly to irAEs.

Conclusions:

• Rituximab is an effective option for selected severe ICI-related irAEs, especially when conventional immunosuppression fails.
• Real-world data support B-cell-targeted therapy for managing complex irAEs.
• Further prospective studies are warranted to confirm these findings.