Immune Checkpoint Inhibitor Rechallenge Research Articles

Immune checkpoint inhibitor (ICI) rechallenge after immune-related adverse events (irAE) requiring hospitalization: A single-center 10-year experience.

e14609 Background: ICI rechallenge after irAE has become a significant clinical dilemma, with irAE recurrence rates of 30-40% after rechallenge. Here we examine factors influencing ICI rechallenge rates across a 10-year period at the Massachusetts General Hospital (MGH), where the Severe Immunotherapy Complications service is available to provide multidisciplinary irAE expertise. Methods: We included patients admitted to MGH for an irAE from August 2011 to July 2023. We collected baseline demographics, ICI regimens, and irAE features. The choice of ICI used at rechallenge was grouped into 3 categories: 1) restarting an ICI within the same class, 2) switching classes (CTLA-4 to PD-(L)1 or vice versa), or 3) de-escalating from combination to monotherapy. Chi-square and Mann-Whitney U tests were applied to descriptive statistics. Results: Among 5882 patients treated with ICI, 671 (11.4%) patients were admitted for irAE. The median age was 67.6 (IQR, 59-74.9) years and 58% were male. Initial ICI regimens consisted of anti-PD-(L)1 (64.8%), anti-CTLA4 (10.9%), and ICI combinations (24.3%). 174 of 671 patients (25.9%) were rechallenged after an irAE requiring hospitalization. Rechallenge was common after rheumatologic, endocrine, dermatologic irAE and GI irAE, but rare after cardiac, neurologic, or pulmonary irAE (Table 1). The median time to rechallenge was 25 days (IQR 18-91) after endocrine irAE and 72 days (IQR 40-209) after non-endocrine irAE (p<0.001). Rechallenge was more common in melanoma (35%, p<0.001), and less common in lung (13.6%, p<0.001) and GU cancers (10%, p=0.003). Rechallenge rates were significantly higher in patients initially on combination therapy (39.6%) versus PD-(L)1 monotherapy (15.5%), p<0.001. Of those rechallenged, 43.2% initially on combination therapy were de-escalated to monotherapy and 53% were restarted within the same class. Amongst the PD-(L)1 monotherapy group, 88.4% were restarted within the same class and 11.6% switched classes. Conclusions: Here we examine practice patterns at a large academic center, where 25.9% of patients with irAE requiring hospitalization were rechallenged. Rechallenge was more prevalent in patients with melanoma or on ICI combination therapy, whereas it was less frequent following cardiac, neurologic, or pulmonary irAE. Under adequate risk-benefit evaluation, close monitoring, and multidisciplinary care, ICI rechallenge can be considered. [Table: see text]

Neurological Adverse Events Related to Immune Checkpoint Inhibitors: A Practical Review.

The increasing use of immune checkpoint inhibitors (ICI) in cancer therapy has brought attention to their associated neurotoxicities, termed neurological immune-related adverse events (n-irAEs). Despite their relatively rare incidence, n-irAEs pose a significant risk, potentially leading to severe, long-lasting disabilities or even fatal outcomes. This narrative review aims to provide a comprehensive overview of n-irAEs, focusing on their recognition and management. The review addresses a spectrum of n-irAEs, encompassing myositis, myasthenia gravis, various neuropathies, and central nervous system complications, such as encephalitis, meningitis, and demyelinating diseases. The key features of n-irAEs are emphasized in this review, including their early onset after initiation of ICIs, potential association with non-neurological irAEs and/or concurrent oncological response, the significance of ruling out other etiologies, and the expected improvement upon discontinuation of ICIs and/or immunosuppression. Furthermore, this review delves into considerations for ICI re-challenge and the intricate nature of n-irAEs within the context of pre-existing autoimmune and paraneoplastic syndromes. It underscores the importance of a multidisciplinary approach to diagnosis and treatment, highlighting the pivotal role of severity grading in guiding treatment decisions.

Clinical Manifestation, Risk Factors, and Immune Checkpoint Inhibitor Rechallenge of Checkpoint Inhibitor-Associated Pneumonitis in Patients With Lung Cancer.

Immune-related adverse effects can lead to damage to various systems of the body, checkpoint inhibitor-associated pneumonitis (CIP) is one of the potentially lethal immune-related adverse effects. However, evidence regarding the risk factors associated with CIP is limited. To timely and accurate identification and prompt treatment of CIP, understanding the risk factors for multimorbidity among diverse study populations becomes crucial. We retrospectively analyzed the clinical data of 1131 patients with lung cancer receiving immunotherapy to identify 110 patients with CIP, the clinical characteristics and radiographic features of patients with CIP were analyzed. A case-control study was subsequently performed to identify the risk factors of CIP. The median treatment cycle was 5 cycles and the median time to onset of CIP was 4.2 months. CIP was mainly grade I or II. Most cases improved after discontinuation of immune checkpoint inhibitors (ICIs) or hormone therapy. Severe CIP tended to occur earlier in comparison to mild to moderate cases. The recurrence rate was 20.6% in ICI-rechallenged patients, and patients with relapsed CIP were usually accompanied by higher-grade adverse events than at first onset. Among the 7 patients with relapse, ICI-associated deaths occurred in 2 patients (28.6%). For rechallenging with ICIs after recovery from CIP, caution should be practiced. Male [odds ratio (OR): 2.067; 95% CI: 1.194-3.579; P = 0.009], history of chest radiation (OR: 1.642; 95% CI: 1.002-2.689; P = 0.049) and underlying lung disease (OR: 2.347; 95% CI: 1.008-5.464; P =0.048) was associated with a higher risk of CIP.

Abstract 5260: Combination activity of eribulin liposomal formulation and anti-PD-1 antibody after tumor regrowth during anti-PD-1 antibody treatment in mice

Abstract Eribulin (ERI) has been reported a microtubule dynamics inhibitor with unique tumor microenvironment modulations such as vascular remodeling activity. In the previous meeting (AACR2022, 2023), we reported that ERI and liposomal formulation of ERI (ERI-LF) also have immunomodulatory activity that induces CD8+ T cells via its vascular remodeling activity and ERI-LF showed more potent immune modulation and combination activities with anti-PD-1 antibody (PD-1 Ab) than ERI in syngeneic mice models and humanized mice models. Although immune-checkpoint inhibitors (ICI) are using as a key drug for various types of cancers in clinical setting, several clinical questions regarding suitable therapies after ICI therapy and efficacy of ICI rechallenge are remaining. In this study, we evaluated anti-tumor activities of combination of ERI-LF and PD-1 Ab in two syngeneic transplantation models using mouse non-small lung cancer cells, P-glycoprotein-knockout (Pgp-KO) KLN205 cells and Pgp-KO LL2 cells. As a result, combination of 1mg/kg ERI-LF (Q7D×2) with PD-1 Ab (200 ug/head, twice a week ×2 weeks) showed significant stronger antitumor activity compared with each monotherapy in only Pgp-KO KLN205 model, in which ERI-LF increased intratumoral microvascular density as a vascular remodeling activity, not in Pgp-KO LL2 model. We next conducted continuous treatment of PD-1 Ab in Pgp-KO KLN205 model to investigate tumor regrowth during treatment of PD-1 Ab. In this model, tumor growth was inhibited by PD-1 Ab until about two weeks after initiation of the treatment and then this inhibitory activity disappeared after two weeks even by continuous treatment of PD-1 Ab. We performed flow cytometry analysis (FCM) for tumor-infiltrating immune cells and RNAseq analysis using regrowing tumors compared with non-treatment tumors. Expressions of mRNA of several immune inhibitory receptors were upregulated in tumors with regrowth, although CD4+ cells and CD8+ cells were also increased in FCM using tumor samples. Furthermore, we investigated anti-tumor activity of combination of ERI-LF and PD-1 Ab against tumors which changed from inhibitory phase to regrowth phase during PD-1 Ab treatment in Pgp-KO KLN205 model. The combination of ERI-LF at 1mg/kg (Q7D×3) and PD-1 Ab (200 ug/head, twice a week ×3 weeks) also showed potent anti-tumor activity against tumors with regrowth by prior PD-1 Ab treatment as well as PD-1 Ab-naïve tumor, suggesting that this combination therapy might be effective after prior ICI therapy. Currently, Phase 1b/2 clinical trial of ERI-LF plus nivolumab in patients with selected solid cancers (NCT04078295) is underway. Patients with or without prior ICI therapy were enrolled in a small cell lung cancer cohort of this clinical study. Our preclinical results might provide a scientific rationale for a uniqueness of ERI-LF as a post ICI therapy. Citation Format: Moe Tamura, Yuki Niwa, Taro Semba. Combination activity of eribulin liposomal formulation and anti-PD-1 antibody after tumor regrowth during anti-PD-1 antibody treatment in mice [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5260.

Efficacy of NSCLC Rechallenge with Immune Checkpoint Inhibitors following Disease Progression or Relapse.

Immune checkpoint inhibitors (ICIs) are at the forefront of advanced non-small-cell lung cancer (NSCLC) treatment. Still, only 27-46% of patients respond to initial therapy with ICIs, and of those, up to 65% develop resistance within four years. After disease progression (PD), treatment options are limited, with 10% Objective Response Rate (ORR) to second or third-line chemotherapy. In this context, ICI rechallenge is an appealing option for NSCLC. Most data on the efficacy of ICI rechallenge are based on retrospective real-world studies of small, heavily pretreated, and heterogeneous patient groups. Despite these limitations, these studies suggest that ICI monotherapy rechallenge in unselected NSCLC patient populations who discontinued initial ICI due to PD is generally ineffective, with a median Progression-Free Survival (PFS) of 1.6-3.1 months and a Disease Control Rate (DCR) of 21.4-41.6%. However, there is a subpopulation that benefits from this strategy, and further characterization of this subgroup is essential. Furthermore, immunotherapy rechallenge in patients who discontinued initial immunotherapy following treatment protocol completion and progressed after an immunotherapy-free interval showed promising efficacy, with a DCR of 75-81%, according to post hoc analyses of several clinical trials. Future research on ICI rechallenge for NSCLC should focus on better patient stratification to reflect the underlying biology of immunotherapy resistance more accurately. In this review, we summarize evidence regarding rechallenge immunotherapy efficacy following NSCLC disease progression or relapse, as well as ongoing trials on immunotherapy rechallenge.

Efficacy and safety analysis of immune checkpoint inhibitor rechallenge therapy in locally advanced and advanced non-small cell lung cancer: a retrospective study.

Immune checkpoint inhibitors (ICIs) have dramatically changed the first-line treatment pattern of non-small cell lung cancer (NSCLC) without driver gene alterations. However, the optimal choice for second-line treatment after initial treatment with ICIs is unclear. This study aimed to clarify the efficacy and safety of ICI rechallenge therapy in locally advanced and advanced NSCLC. We retrospectively analyzed the histories of 224 patients with locally advanced or advanced NSCLC treated with programmed death-1 (PD-1)/programmed death-ligand 1 (PD-L1) inhibitors alone or in combination with chemotherapy and/or antiangiogenic therapy in first-line treatment. Progression-free survival 2 (PFS2) was the time from the first defined progress disease (PD) to the second disease progression or death. Efficacy evaluation was performed directly in accordance with RECIST v1.1 criteria. Adverse events (AEs) were graded following the National Cancer Institute Common Terminology Criteria for Adverse Events v5.0. Survival data were estimated using the Kaplan-Meier method or Cox survival regression model and compared using the log-rank test in overall cohort and other subgroups. There were no significant differences in objective response rate (ORR) and median PFS2 (mPFS2) between the ICI rechallenge group and non-rechallenge group (ORR: 10.3% vs. 15.3%, P=0.308; mPFS2: 5.33 vs. 4.40 months, P=0.715). And the ICI rechallenge group showed no new safety signals compared with non-rechallenge group. In ICI rechallenge group, patients resistant to first-line immunotherapy had a lower ORR and shorter PFS2 compared with those who responded to initial ICIs treatment (ORR: 7.0% vs. 17.6%, P=0.038; mPFS2: 3.68 vs. 5.91 months, P=0.014). No significant difference in mPFS2 was observed among different second-line treatment groups (P=0.362). Radiotherapy in second-line treatment and ICI rechallenge therapy were not the main factors affecting PFS2. ICI rechallenge therapy beyond disease progression did not improve clinical outcomes in patients with NSCLC, but no new safety signals emerged. However, patients with favorable response to initial ICIs treatment still showed significant efficacy of subsequent ICI rechallenge therapy.

Immune checkpoint inhibitors and acute kidney injury.

As a new type of anti-tumor immunotherapy, immune checkpoint inhibitors (ICIs) have improved the prognosis of multiple malignancies. However, renal complications are becoming more frequent. Nephrotoxicity often manifests as acute kidney injury (AKI), and the most common histopathological type is acute tubulointerstitial nephritis (ATIN). Based on previous studies of the incidence and potential risk factors for nephrotoxicity, in this review, we describe the mechanism of AKI after ICIs treatment, summarize the incidence, risk factors, and outcomes of AKI, and discuss the diagnosis and management of immune checkpoint inhibitors-associated acute kidney injury (ICI-AKI). In addition, we review the current status of ICIs rechallenge and the therapeutic strategies of ICIs applied in kidney transplant recipients. Finally, we emphasize the importance of collaboration between nephrologists and oncologists to guide the treatment of ICIs and the management of renal complications.

Immunotherapy in Gastric Cancer: A Review

Globally, gastric cancer (GC) ranks fourth in terms of cancer-related mortality. Patients diagnosed with advanced gastric cancer (AGC) frequently have a median survival around 12-15 months, depending to the therapy. Immunotherapy is becoming an essential therapeutic strategy in medical oncology, and it is projected to make major advances to the way gastric cancer cure. The phase III ATTRACTION-2 showed that nivolumab, a monoclonal antibody targeting programmed cell death 1 (PD-1), substantially increased overall survival (OS) in patients with advanced gastric cancer (AGC) when given as a third- or later-line treatment, as compared to a placebo. Furthermore, nivolumab in combination with 5-fluorouracil and platinum as a first-line treatment increased OS in patients with human epidermal growth factor receptor-2 (HER2)-negative AGC in the international phase III CheckMate-649 investigation. Pembrolizumab, an additional anti PD-1 antibody, when used with trastuzumab and cytotoxic chemotherapy as first line treatment, demonstrated a substantial enhancement in the overall response rate among patients diagnosed with HER2-positive AGC. Hence, immune checkpoint inhibitors (ICIs) are crucial in the present management of GC. Current research is actively investigating alternative treatment following ICI combination therapy, including ICI rechallenge or combination therapy with drugs that have distinct mechanisms of action. Several clinical trials are presently being done to employ immunotherapy as a treatment option in the perioperative and postoperative settings for patients with early gastric cancer, based on the success of immunotherapy in treating advanced gastric cancer (AGC). This article gives an overview of the recent breakthroughs in immunotherapy.

Safety and efficacy of immune checkpoint inhibitor rechallenge in advanced non-small cell lung cancer: a retrospective study

We conducted a retrospective study to evaluate the efficacy of immune checkpoint inhibitor (ICI) rechallenge in patients with advanced non-small cell lung cancer (NSCLC). The study included 111 patients who had previously received ICI therapy and experienced disease progression. The primary endpoints assessed were overall survival (OS), progression-free survival (PFS), and objective response rate (ORR). Our findings revealed that the ICI rechallenge showed promising results in improving patient outcomes. OS (r) is the time from rechallenging with immune checkpoint inhibitors to the last follow-up or death from any cause. The median OS (r) was 14.3 months (95% CI 11.3–17.3 months), with a median PFS (r) of 5.9 months (95% CI 4.1–7.7 months). The ORR was 17.1%; the DCR was 82.3%. Subgroup analysis demonstrated that patients without brain or liver metastases had a longer OS (r) compared to those with metastases (21.6 vs. 13.8 months, χ2 = 3.873, P = 0.046; 20.8 vs. 9.1 months, χ2 = 10.733, P = 0.001, respectively). Moreover, patients without driver gene mutations exhibited significantly longer OS than those with mutations or wild-type patients (22.9 vs. 16.1 vs. 7.5 months, χ2 = 10.710, P = 0.005). Notably, patients who switched to a different ICI during the rechallenge had shorter OS than those who did not change medications (10.4 vs. 21.1 months, χ2 = 9.014, P = 0.003). The incidence of immune-related adverse events did not significantly differ between the two treatment phases. These findings suggest that ICI rechallenge may be a viable therapeutic strategy for select NSCLC patients. Further prospective studies are needed to validate these results and guide treatment decisions for advanced NSCLC.

Immune Checkpoint Inhibitor-Associated Myocarditis: A Literature Review.

Recently in the field of oncology, immune checkpoint inhibitors (ICI) are being increasingly utilized both in clinical trials and in clinical practice. It is a form of biological therapy that targets tumors by activating the immune system, which in turn eliminates proliferating cancer cells. These have numerous immune-related adverse events (irAEs), one of which is myocarditis, which has high rates of mortality. This article was a narrative review of myocarditis related to ICI use. Studies from the PubMed, Cochrane, and American Society of Clinical Oncology (ASCO) databases were used in writing this review. The databases were searched for original publications for adverse effects related to ICI use and myocarditis specifically.There are numerous published instances of cancer immunotherapy causing myocarditis. ICI therapy has numerous benefits, as it upregulates the immune system to target cancer cells, utilizing the body's own defense mechanisms to target proliferating cells. Myocarditis is a serious side effect, however. Therefore, on balance, these monotherapies are worth using. While this literature review primarily identifies cross-reaction as the main mechanism of myocarditis, there are other possible mechanisms. One proposed mechanism involves a shared antigen between the myocardial tissue and the tumor. This mechanism is called molecular mimicry, where the monoclonal antibody attacks both the myocardial tissue and the tumor cell. Management of ICI-induced myocarditis has not been studied by randomized controlled trials or prospective studies, but based on previous case reports and case series it is mostly treated with steroids initially. An ICI rechallenge after temporary discontinuation appears conceivable in many cases, especially given its therapeutic effects, but only limited data are available on the safety of a rechallenge after an irAE. The lack of RCTs regarding rechallenge with an ICI after irAE, more so specifically about myocarditis, along with the overall results and the complexity involved in such cases once again emphasize the need to make decisions on an individual basis by a multidisciplinary expert working group. At the same time, the focus should also be on publishing more data as the need will grow along with the indications for ICI therapies.

Rechallenge of immune checkpoint inhibitors in advanced non-small cell lung cancer.

Immune checkpoint inhibitor (ICI) rechallenge in non-small cell lung cancer (NSCLC) is a promising therapeutic strategy. The situation for ICI rechallenge can be divided into three categories: adverse events (AEs); resistance to ICIs, and rechallenge becomes compulsive because of tumor relapse while the patients had completed a 2 year course of immunotherapy. However, these categories are still controversial and should be explored further. Through voting at the 6th Straits Summit Forum on Lung Cancer, in this study we summarize the consensus of 147 experts in ICI rechallenges. A total of 97.74% experts agreed to rechallenge; 48.87% experts rechallenge with the original drug, and the others rechallenge with a different drug; 40.3% agreed to rechallenge directly after progression; 88.06% experts agreed to ICI rechallenge with a combination regimen; and factors such as previous performance status score, PD-1 expression, and age should also be considered. Understanding the the clinical studies in ICI rechallenge could bring us one step closer to understanding the consensus. In patients with advanced NSCLC who have suffered recurrent or distant metastasis after immunotherapy, the option of rechallenge with ICIs is a promising treatment option.

Clinical characteristics and novel strategies of immune checkpoint inhibitor rechallenge therapy for non-small cell lung cancer: a comprehensive review.

Treatment of non-small-cell lung cancer (NSCLC) has entered the immunotherapy era, marked by significant survival improvements due to the use of immune checkpoint inhibitors (ICIs). However, owing to factors, such as disease progression, long-term use, and side effects, some patients discontinue immunotherapy, resulting in limited subsequent treatment option and a negative impact on their survival and quality of life. We have collected relevant data which reveal that ICI rechallenge may be an effective clinical strategy. However, many factors affect the efficacy of rechallenge, including patient characteristics, initial treatment drugs, treatment duration, efficacy, toxicity, and side effects. Additionally, the side effects of rechallenge and mechanisms of reversing drug resistance play crucial roles. Identifying suitable candidates, optimizing treatment plans and duration, enhancing treatment efficacy, and minimizing toxicity and adverse effects in rechallenges are pressing clinical needs. Addressing these issues can provide guidance for the clinical use of immunotherapy rechallenges to better serve patients. This review focuses on the clinical considerations and strategies for immune therapy rechallenges in NSCLC.

Safety and Efficacy Outcomes in Immune Checkpoint Inhibitor-Treated Patients With Metastatic Urothelial Carcinoma Requiring Treatment Interruption or Discontinuation Due to Immune-Related Adverse Events

IntroductionAs most patients with metastatic urothelial carcinoma (mUC) will be treated with immune checkpoint inhibitors (ICI), familiarity with their associated immune-related adverse events (irAEs) is critical. We describe the characteristics and outcomes of ICI-treated mUC patients who experienced irAEs requiring treatment interruption (TI) or permanent discontinuation. Materials and MethodsICI-treated mUC patients who developed grade ≥2 irAEs were reviewed. Clinical-, treatment-, and toxicity-related data were evaluated. Toxicity was graded per common terminology for categorization of adverse events v5.0. Cohorts were divided into patients who underwent ICI rechallenge and those who required permanent ICI discontinuation. Time to treatment interruption (TTI), time to next treatment, and duration of clinical benefit were assessed descriptively. Progression-free survival and overall survival (OS) were estimated using Kaplan-Meier methodology. ResultsOf 200 ICI-treated mUC patients at Cleveland Clinic between October 2015 and October 2020, 16 (8%) experienced ≥ grade 2 irAEs necessitating TI. Median TTI among all patients was 6.5 months (range, 1-19). Eleven patients (69%) required corticosteroids. ICI were held and rechallenged in 10 patients (62%) and permanently discontinued in 6 patients (38%). Of the 10 ICI-rechallenged patients, 7 (70%) experienced another irAE upon rechallenge with median time to irAE recurrence of 2.9 months (range, 0.1-10.9); 3 (30%) eventually discontinued ICI due to recrudescent irAEs. Four (40%) of the 10 ICI-rechallenged patients received subsequent therapy. Five (83%) of the 6 patients who permanently discontinued ICI demonstrated durable clinical benefit off therapy with median duration of clinical benefit 17.7 months (range, 14.2-55.2). Two-year OS was 40% (95% CI: 19%-86%) in the ICI rechallenge cohort and 67% (95% CI: 38%-100%) in the permanent discontinuation cohort. ConclusionICI-treated mUC patients who developed irAEs requiring TI had a high rate of subsequent irAEs upon ICI rechallenge. Importantly, patients who permanently discontinued ICI due to irAE demonstrated durable clinical benefit off treatment.

Immune checkpoint inhibitor-induced colitis with endoscopic evaluation in Chinese cancer patients: a single-centre retrospective study

BackgroundWe investigated the clinical and endoscopic features, management strategies, and outcomes of Chinese cancer patients with immune checkpoint inhibitor (ICI)-induced colitis.MethodThis single-centre retrospective study included patients who developed ICI-induced colitis and underwent endoscopic evaluation from June 1, 2019 to October 1, 2023. We analysed clinical features, ICI-induced colitis-related information, management strategies, and outcomes.ResultsA total of 25 patients were included; most were male (88%) with a median age of 59 years. Eleven (44%) patients had grade 2 colitis, and 14 (56%) had grade 3 colitis. The median time from ICI initiation to colitis onset was 105 days. The median duration from symptom onset to endoscopic evaluation was 11 days. Regarding endoscopic evaluation, colitis involved the entire colon in 13 (52%) patients, and 15 (60%) had ulcers. Twenty-three (92%) patients received steroids, and 3 (12%) added infliximab (IFX). Most patients (n=19, 76%) achieved remission with complete tapering of the steroid taken for the first colitis episode. Among the 6 (24%) patients who did not taper initial, 5 patients increased their steroid dosage with 2 added IFX, leading to symptom remission and successful steroid tapering, while one patient experienced continuous non-remission despite increasing the steroid and receiving two infusions of IFX. Of the 8 (32%) ICI rechallenge patients, 4 achieved long-lasting benefit without colitis recurrence. The other 4 experienced recurrent colitis after ICI rechallenge and permanently discontinued ICIs. The median duration from ICI rechallenge to colitis recurrence was shorter than the time to colitis onset. One patient developed steroid-refractory colitis and recovered with one infusion of IFX.ConclusionEndoscopy has value in the evaluation and optimal management of ICI-induced colitis in Chinese cancer patients. IFX is necessary for treating colitis, especially in steroid-refractory/resistant patients. ICI rechallenge can achieve benefit, but permanently discontinuing ICIs is needed if colitis recurs. Future large-scale prospective studies are required for more accurate assessments and validation.

Immune checkpoint inhibitor rechallenge in patients who previously experienced immune-related inflammatory arthritis: a multicentre observational study

ObjectiveAnother course of immune checkpoint inhibitors (ICIs) is often considered in patients with cancer progression and previous immune-related adverse events, including inflammatory arthritis (ICI-IA), but there are limited data regarding...

2176P Rechallenge of immune checkpoint inhibitors after immune-related adverse events: A systematic review

2176P Rechallenge of immune checkpoint inhibitors after immune-related adverse events: A systematic review

Occurrence of irAEs after Immune Checkpoint Inhibitor Rechallenge: An Updated Meta-Analysis

What Is Known? and Objective. Immune checkpoint inhibitors (ICIs) play an important role in various cancers. The efficacy and safety of rechallenge with ICIs after immune-related adverse events (irAEs) were not well known. Accumulating studies report inconsistent findings. Thus, we conducted an updated meta-analysis by including more studies. Methods. We searched PubMed, Web of Science, Embase, and Cochrane Library for studies reporting the rechallenge of ICIs after irAEs. The evaluation outcomes included the incidence of irAEs, objective response rate (ORR), and disease control rate (DCR). Results and Discussion. A total of 896 ICI rechallenge cases from 24 studies were included. Compared to the initial treatment with ICIs, rechallenge showed a higher incidence of all-grade irAEs (OR, 2.78; 95% CI, 1.51–5.10; p = 0.001 ) and high-grade irAEs (OR, 1.88; 95% CI, 1.27–2.78; p = 0.002 ), but ORR (OR, 1.01; 95% CI, 0.55–1.84; p = 0.97 ) and DCR (OR, 1.21; 95% CI, 0.68–2.15; p = 0.52 ) were not further improved after the rechallenge of ICIs. What Is New? and Conclusion. More studies are included in this paper to compare and analyze the efficacy and safety of ICIs after rechallenge, so as to update the previous meta-analyses, and finally get different conclusions from the previous meta-analyses in terms of safety. Our results suggest that rechallenged ICIs after irAEs showed similar efficacy and lower safety than initial ICIs. However, these results need to be further verified by high-quality studies with large samples. In addition, we added subgroup analysis not available in previous meta-analyses to explore the association of cancer type, age, and gender factors with the incidence of irAE after ICI rechallenge.

Efficacy and safety of immune checkpoint inhibitor rechallenge in non-small cell lung cancer: A systematic review and meta-analysis.

The aim of the study was to explore the efficacy and safety of immune checkpoint inhibitor (ICI) rechallenge in patients with non-small cell lung cancer (NSCLC). Studies that enrolled NSCLC patients treated with two lines of ICIs were included using four databases. The initial line (1L-) and subsequent lines (2L-) of ICIs were defined as 1L-ICI and 2L-ICI, respectively. A total of 17 studies involving 2100 patients were included. The pooled objective response rate (ORR), disease control rate (DCR), median progression-free survival (mPFS), and median overall survival (mOS) for 2L-ICIs were 10%, 50%, 3.0 months, and 13.1 months, respectively. The 2L-ICI discontinuation rates caused by toxicities ranged from 0% to 23.5%. Original data were extracted from six studies, covering 89 patients. Patients in whom 1L-ICIs were discontinued following clinical decision (the mPFS of 2L-ICIs was not reach) achieved a more prolonged mPFS of 2L-ICIs than those due to toxicity (5.2 months) and progressive disease (2.1 months) (p < 0.0001). Patients' 1L-PFS for more than 2-years had preferable 2L-ORR (35.0% vs. 9.8%, p = 0.03), 2L-DCR (85.0% vs. 49.0%, p = 0.007), and 2L-mPFS (12.4 vs. 3.0 months, p < 0.0001) than those less than 1-year. Patients administered the same drugs achieved a significantly prolonged mPFS compared with the remaining patients (5.4 vs. 2.3 months, p = 0.0004), and those who did not accept antitumor treatments during the intervals of two lines of ICIs achieved a prolonged mPFS compared to those patients who did accept treatments (7.6 vs. 1.9 months, p < 0.0001). ICI rechallenge is a useful therapeutic strategy for NSCLC patients, especially suitable for those who achieve long-term tumor remission for more than 2-years under 1L-ICIs.

Efficacy of Immune Checkpoint Inhibitor (ICI) Rechallenge in Advanced Melanoma Patients' Responders to a First Course of ICI: A Multicenter National Retrospective Study of the French Group of Skin Cancers (Groupe de Cancérologie Cutanée, GCC).

The long-term effectiveness of immune checkpoint inhibitor (ICI) rechallenge for progressive or recurrent advanced melanoma following previous disease control induced by ICI has not been thoroughly described in the literature. In this retrospective multicenter national real-life study, we enrolled patients who had been rechallenged with an ICI after achieving disease control with a first course of ICI, which was subsequently interrupted. The primary objective was to evaluate tumor response, while the secondary objectives included assessing the safety profile, identifying factors associated with tumor response, and evaluating survival outcomes. A total of 85 patients from 12 centers were included in the study. These patients had advanced (unresectable stage III or stage IV) melanoma that had been previously treated and controlled with a first course of ICI before undergoing rechallenge with ICI. The rechallenge treatments consisted of pembrolizumab (n = 44, 52%), nivolumab (n = 35, 41%), ipilimumab (n = 2, 2%), or ipilimumab plus nivolumab (n = 4, 5%). The best overall response rate was 54%. The best response was a complete response in 30 patients (35%), a partial response in 16 patients (19%), stable disease in 18 patients (21%) and progressive disease in 21 patients (25%). Twenty-eight adverse events (AEs) were reported in 23 patients (27%), including 18 grade 1-2 AEs in 14 patients (16%) and 10 grade 3-4 AEs in nine patients (11%). The median progression-free survival (PFS) was 21 months, and the median overall survival (OS) was not reached at the time of analysis. Patients who received another systemic treatment (chemotherapy, targeted therapy or clinical trial) between the two courses of ICI had a lower response to rechallenge (p = 0.035) and shorter PFS (p = 0.016). Rechallenging advanced melanoma patients with ICI after previous disease control induced by these inhibitors resulted in high response rates (54%) and disease control (75%). Therefore, ICI rechallenge should be considered as a relevant therapeutic option.

Role of Underlying Liver Pathology in the Development of Immune-Related Hepatitis: A Case-Control Study.

Immune-related hepatitis (irH) is a serious immune-related adverse event (IRAE) that may result in morbidity, immune checkpoint inhibitor (ICI) therapy interruption and, rarely, mortality. The impact of underlying liver pathology, including liver metastasis, on the incidence of irH remains poorly understood. We hypothesized that the presence of underlying liver pathology increased the risk of irH in patients with cancer treated with ICI. We conducted a retrospective case-control study of irH in patients with cancer receiving first ICI treatment from 2016-2020. Provider documented cases of ≥ grade 2 irH were identified and control matched in a 2:1 ratio based on age, sex, time of ICI initiation, and follow-up time. Conditional logistic regression was used to estimate the relationship between irH and liver metastasis at ICI initiation. Ninety-seven cases of irH were identified, 29% of which had liver metastases at time of ICI initiation. Thirty-eight percent of patients developed grade 2, 47% grade 3, and 14% grade 4 irH. When adjusted for covariates/confounders, the presence of liver metastasis was associated with increased odds of irH (aOR 2.79 95% CI 1.37-5.66, p = 0.005). The presence of liver metastases did not correlate with irH grade or rate of irH recurrence after ICI rechallenge. Presence of liver metastases increased the odds of irH in patients with first-time ICI therapy. Limitations include the retrospective nature, moderate sample size, possible selection bias and confounding. Our findings are hypothesis-generating and warrant external validation as well as tissue and circulating biomarker exploration.