Safety of Immunotherapy Rechallenge After Immune-related Adverse Events in Patients With Advanced Cancer
Adi Kartolo, Ryan Holstead, Sidra Khalid, Jeffrey Emack, Wilma M. Hopman, Tara Baetz
Abstract
This retrospective study aimed to investigate the safety profile of continuing or rechallenging patients with advanced cancer who developed grade≥2 immune-related adverse events (irAEs) on immunotherapy-based regimens. Our study had 25, 20, and 40 patients (N=85) in the Treatment Continuation (TCG), Non-Rechallenge (NRG), and Rechallenge Groups (RG), respectively. Subsequent irAEs recurrence were more common in RG than TCG and NRG (78% vs. 56% vs. 25%, P<0.001). The same subsequent irAEs recurrences occurred on 42% of RG, 4% of TCG, and 15% of NRG (P<0.001). On the RG, there was a nonstatistical trend of shortening interval time between time from treatment rechallenge to subsequent irAEs when compared with time from first treatment to initial grade≥2 irAEs (5.86 vs. 8.86 wk, P=0.114). Patients who had cardiac irAEs were not rechallenged. Several high-risk features were identified to prognosticate risk of irAEs recurrences upon treatment rechallenge, including age 65 years and above (P=0.007), programmed cell death protein 1 inhibitors (P<0.001), grade 3 irAEs (P=0.003), pneumonitis type (P=0.048), any systemic corticosteroid use (P=0.001)/high-dose systemic corticosteroid use (P=0.007)/prolonged ≥4-week corticosteroid use (P=0.001) for irAEs management, and early development of irAEs (P=0.003). Our study concluded that it was relatively safe to continue or rechallenge patients with advanced cancers on immunotherapy-based regimens postdevelopment of certain grade≥2 irAEs, except for cardiac, neurological, or any grade 4 irAEs. Subsequent irAEs were common, no more severe, involved the same organ sites, and occurred more quickly than the original irAE. Close monitoring of all potential irAEs is required when rechallenging a patient on immunotherapy, especially for patients with high-risk features.