Safety of immune checkpoint inhibitor rechallenge after discontinuation for grade ≥2 immune-related adverse events in patients with cancer.

Safety of rechallenge of immune checkpoint inhibitor (ICI) after grade ≥2 immune-related adverse events (irAEs) leading to ICI discontinuation remains unclear. All adverse drug reactions involving at least one ICI reported up to December 31, 2019 were extracted from the French pharmacovigilance database. Patients were included if they experienced at least one grade ≥2 irAE resulting in ICI discontinuation, with subsequent ICI rechallenge. The primary outcome was the recurrence of at least one grade ≥2 irAE in these patients after ICI rechallenge. We included 180 patients: 61.1% were men (median age of 66 years), 43.9% had melanoma and 78.9% were receiving anti-programmed cell death 1. First ICI discontinuation was related to 191 irAEs. After ICI rechallenge, 38.9% of the patients experienced at least one grade ≥2 irAE. Among them, 70.0% experienced the same irAE, 25.7% a distinct irAE, and 4.3% both the same and a distinct irAE. Lower recurrence rates of irAEs were associated with rechallenge with the same ICI treatment (p=0.02) or first endocrine irAEs (p=0.003). Gastrointestinal irAEs were more likely to recur (p=0.007). The median duration from ICI discontinuation to rechallenge and the severity of the initial irAE did not predict recurrent irAEs after ICI rechallenge (p=0.53 and p=0.40, respectively). In this study, 61.1% of the patients who discontinued ICI treatment for grade ≥2 irAEs experienced no recurrent grade ≥2 irAEs after ICI rechallenge. Although ICI rechallenge appears to be safe under close monitoring, it should always be discussed balancing usefulness of rechallenge, patient comorbidities and risk of recurrence of first irAE(s). Due to inherent bias associated with pharmacovigilance studies, further prospective studies are needed to assess risk factors that may influence patient outcomes after ICI rechallenge.

Allouchery M ，Lombard T ，Martin M ，Rouby F ，Sassier M ，Bertin C ，Atzenhoffer M ，Miremont-Salame G ，Perault-Pochat MC ，Puyade M ，French Network of Regional Pharmacovigilance Centers ... -  《Journal for ImmunoTherapy of Cancer》

Immune Checkpoint Inhibitor Rechallenge After Immune-Related Adverse Events in Patients With Cancer.

Dolladille C ，Ederhy S ，Sassier M ，Cautela J ，Thuny F ，Cohen AA ，Fedrizzi S ，Chrétien B ，Da-Silva A ，Plane AF ，Legallois D ，Milliez PU ，Lelong-Boulouard V ，Alexandre J ... -  《-》

Safety and Efficacy of the Rechallenge of Immune Checkpoint Inhibitors After Immune-Related Adverse Events in Patients With Cancer: A Systemic Review and Meta-Analysis.

Little evidence exists on the safety and efficacy of the rechallenge of immune checkpoint inhibitors (ICIs) after immune-related adverse events (irAEs) in patients with cancer. We searched PubMed, Web of Science, Embase, and Cochrane for articles on ICI rechallenge after irAEs for systemic review and meta-analysis. The outcomes included the incidence and associated factors for safety and objective response rate (ORR) and disease control rate (DCR) for efficacy. A total of 789 ICI rechallenge cases from 18 cohort studies, 5 case series studies, and 54 case reports were included. The pooled incidence of all-grade and high-grade irAEs after rechallenge in patients with cancer was 34.2% and 11.7%, respectively. Compared with initial ICI treatment, rechallenge showed a higher incidence for all-grade irAEs (OR, 3.81; 95% CI, 2.15-6.74; p < 0.0001), but similar incidence for high-grade irAEs (p > 0.05). Types of initial irAEs (pneumonitis and global irAEs) and cancer (non-small cell lung cancer and multiple cancer) recapitulated these findings. Gastrointestinal irAEs and time interval between initial irAEs and ICI rechallenge were associated with higher recurrence of high-grade irAEs (p < 0.05), whereas initial anti-PD-1/PD-L1 antibodies were associated with a lower recurrence (p < 0.05). Anti-PD-1/PD-L1 antibodies rechallenge was associated with a lower all-grade irAE recurrence (p < 0.05). The pooled ORR and DCR after rechallenge were 43.1% and 71.9%, respectively, showing no significant difference compared with initial ICI treatment (p > 0.05). ICI rechallenge after irAEs showed lower safety and similar efficacy outcomes compared with initial ICI treatment. PROSPERO, identifier CRD42020191405.

Zhao Q ，Zhang J ，Xu L ，Yang H ，Liang N ，Zhang L ，Zhang F ，Zhang X ... -  《Frontiers in Immunology》

Durable responses in patients with genitourinary cancers following immune checkpoint therapy rechallenge after moderate-to-severe immune-related adverse events.

Immune checkpoint therapy (ICT) prolongs survival in subsets of patients with cancer but can also trigger immune-related adverse events (irAEs) requiring treatment discontinuation. Recent studies have investigated safety of ICT rechallenge after irAEs, and evidence suggests that rechallenge may be associated with improved antitumor responses. However, data are limited on response duration after ICT rechallenge, particularly after severe irAEs. To evaluate safety and efficacy of ICT rechallenge after moderate-to-severe irAEs in patients with renal cell carcinoma (RCC), urothelial carcinoma (UC), and prostate cancer. In this retrospective cohort study, medical records from September 25, 2013, to June 1, 2020, for patients with genitourinary (GU) cancers at MD Anderson Cancer Center who were rechallenged with the same or different ICT following irAEs were reviewed. Demographics, ICT exposure, irAEs (grade and treatment), ICT discontinuation or rechallenge, rates of subsequent irAEs (new or recurrent) and antitumor activity (objective response rates and response duration) were reviewed. Sixty-one patients with RCC, UC, and prostate cancer were rechallenged with ICT after experiencing 105 total irAEs. Objective response rates after rechallenge, that is, upgrade in response, were 14% in RCC (4/28), 21% in UC (3/14), and 0% in prostate cancer. All seven patients who achieved upgrade in response had initial grade 2 or 3 irAEs. Responses were durable among these seven patients, with median radiographic progression-free survival not reached (range: 3.7-66.4 months) as of the March 8, 2021, data cut-off (median follow-up 40.9 months (95% CI 35.3 to 46.5)). All achieved complete response except one patient who was lost to follow-up. The rate of subsequent grade 3 or 4 irAEs after rechallenge was 30%, with no fatal irAEs. The rate of recrudescence of the same irAE was 26% (16/61). 54% of patients received corticosteroids (33/61), and 21% received targeted immunosuppression (13/61) for the initial irAEs. ICT rechallenge after moderate-to-severe irAEs was associated with deep and durable responses in a subset of patients with RCC and UC, with acceptable safety and no fatal events. Strategies to enable ICT resumption after moderate-to-severe irAEs, such targeted immunosuppression, warrant further study.

Siddiqui BA ，Gheeya JS ，Goswamy R ，Bathala TK ，Surasi DS ，Gao J ，Shah A ，Campbell MT ，Msaouel P ，Goswami S ，Wang J ，Zurita AJ ，Jonasch E ，Corn PG ，Aparicio AM ，Siefker-Radtke AO ，Sharma P ，Subudhi SK ，Tannir N ... -  《Journal for ImmunoTherapy of Cancer》

Patterns and outcomes of immune-related adverse events in solid tumor patients treated with immune checkpoint inhibitors in Thailand: a multicenter analysis.

Most immune-related adverse event (irAE) patterns and treatment guidelines are based on western clinical data. We evaluated the incidence and patterns of irAEs in patients treated with immune-checkpoint inhibitors (ICI) in Thailand. All solid tumor patients treated with ICIs were retrospectively reviewed in a multicenter analysis. The study aims to evaluate the incidence of irAEs and their characteristics, treatments, outcomes, and impact on survival. All irAEs were graded using the CTCAE version 4.0. Characteristics of irAEs including time to onset, duration of irAEs, specific treatments, and outcomes of irAEs were reviewed. The Chi-square or Fisher's exact test was used to compare variables. Overall survival (OS) was estimated by the Kaplan-Meier method, and compared by the log-rank test. A p-value < 0.05 was considered statistically significant. irAEs of any grade were observed in 98 of 414 patients (24%), whereas grades 3-4 irAEs were observed in 5.6%. The majority of patients (78%) were treated with monotherapy ICI (anti-PD1/PD-L1 92%). The most common all-grade irAEs were hypothyroidism (7.5%), hepatitis (6.5%), and rash (4.8%). Median onset of overall irAEs was 63 days. Pancreatitis and pneumonitis had the earliest onset at 30 and 34 days, respectively. ICIs were rechallenged in 68 of 98 patients with irAE. Eleven of sixty-eight patients (11.2%) with initial irAE had reoccurrence after ICI rechallenge. Based on a multivariate analysis, pre-existing hypothyroidism, ICI used in a clinical trial setting, and combinations of ICI/ICI were independent factors predicting irAE occurrence. Patients with irAE had a statistically significant longer overall survival (OS) when compared to patients without irAE (p = 0.019). A multivariate analysis revealed that occurrence of irAE was an independent prognostic factor for OS (HR 0.70, 95% CI 0.51-0.96; p = 0.028). irAE was commonly observed in Thai cancer patients treated with ICIs. Most irAEs were low-grade and manageable. Re-occurrence of irAE after re-challenging ICI was not uncommonly observed. Patients who experienced irAEs might have significantly longer OS compared to patients without irAEs. However, OS in this study should be interpreted with caution since it might be affected by various tumor types, treatment settings, dosing schedule, and ICI combinations.

Ngamphaiboon N ，Ithimakin S ，Siripoon T ，Sintawichai N ，Sriuranpong V ... -  《BMC CANCER》