Reactions and adverse events induced by T-cell engagers as anti-cancer immunotherapies, a comprehensive review.

T-cell engagers (TCE) are cancer immunotherapies that have recently demonstrated meaningful benefit for patients with hematological malignancies and solid tumors. The anticipated widespread use of T cell engagers poses implementation challenges and highlights the need for guidance to anticipate, mitigate, and manage adverse events. By mobilizing T-cells directly at the contact of tumor cells, TCE mount an obligatory and immediate anti-tumor immune response that could result in diverse reactions and adverse events. Cytokine release syndrome (CRS) is the most common reaction and is largely confined to the first drug administrations during step-up dosage. Cytokine release syndrome should be distinguished from infusion related reaction by clinical symptoms, timing to occurrence, pathophysiological aspects, and clinical management. Other common reactions and adverse events with TCE are immune effector Cell-Associated Neurotoxicity Syndrome (ICANS), infections, tumor flare reaction and cytopenias. The toxicity profiles of TCE and CAR-T cells have commonalities and distinctions that we sum-up in this review. As compared with CAR-T cells, TCE are responsible for less frequently severe CRS or ICANS. This review recapitulates terminology, pathophysiology, severity grading system and management of reactions and adverse events related to TCE.

Toxicity of immunotherapy combinations with chemotherapy across tumor indications: Current knowledge and practical recommendations.

Chemotherapy associated with Immune Checkpoint Inhibitors is currently the standard of care in several tumor indications. This combination approach improves progression free survival (PFS), overall survival (OS) and complete pathological response (pCR) in several cancer types both in the early and metastatic approaches. However, the distinct spectrum of toxicities between cytotoxic side effects and immune related adverse events (irAEs) with similar clinical presentations and different management strategies remains a challenge in daily practice for healthcare professionals. This review summarizes the most common toxicities reported in the randomized clinical trials that led to the subsequent FDA approval of these combinations, across tumor indications. We cite in particular: non-small cell lung cancer, small cell lung cancer, triple negative breast cancer, squamous cell carcinoma of the head and neck, gastric carcinoma, esophageal carcinoma, cervical carcinoma and biliary tract carcinoma. We found that the combination of chemotherapy and immunotherapy was associated with an increased incidence of all grade adverse events (RR 1.11 [1.09; 1.12]) without an excess in treatment related mortality when compared to chemotherapy alone. We report also an increase in the incidence of serious adverse events (grade ≥ 3) (RR 1.16 [1.10;1.24]); in particular: high grade diarrhea, dyspnea, fatigue, rash and elevated liver enzymes. Together with the collaboration of our institutional network of organ specialists with expertise in irAEs, we propose practical recommendations for physicians to enhance clinical care and management of patients undergoing treatment with combined ICI immunotherapy and chemotherapy.

Immunosuppressant mycophenolate mofetil for patients with steroid-refractory immune-related hepatitis induced by checkpoint inhibitors in oncology.

BACKGROUND: Immune-checkpoint inhibitor (ICI) hepatitis, which does not improve with steroids and requires additional immunosuppressant, is defined as steroid-refractory ICI hepatitis. The outcome of patients with steroid-refractory ICI hepatitis remains poorly determined. Herein, we investigated the incidence, clinical features, and outcome of patients treated with second-line immunosuppressant for steroid-refractory ICI hepatitis. METHODS: This is a retrospective analysis of patients who presented ICI hepatitis from 1st June 2016 to 30th September 2022. Steroid-refractory ICI hepatitis was defined as no clinical and biological improvement after systemic steroid therapy ≥1 mg/kg/d. Main objectives were to assess the frequency and risk factors associated with steroid-refractory ICI hepatitis and to evaluate the efficacy of second-line immunosuppressants. RESULTS: In total, 130 patients with grade ≥3 ICI hepatitis were screened, of them 60 (46.2%) were treated with systemic steroids. In total, 11/130 (8.5%) had steroid-refractory hepatitis. Statistically significant factors associated with steroid-refractory hepatitis included previous liver comorbidities (54.5% versus 11.6%; p < 0.01), hyperbilirubinemia (p < 0.001), and general symptoms (fever, jaundice, ascites, and/or encephalopathy) associated with hepatitis (72.7% versus 30.8%; p = 0.015). The 11 patients with steroid-refractory hepatitis were treated with mycophenolate mofetil. In total, resolution or return to grade ≤1 for hepatitis was observed in 81.8% (9/11) of patients. CONCLUSIONS: Steroid-refractory ICI hepatitis accounted for 8.5% of patients with grade ≥3 immune-related hepatitis and was statistically associated with previous liver comorbidities, hyperbilirubinemia, and general symptoms. Mycophenolate mofetil was a suitable option of therapy for steroid-refractory ICI hepatitis.

[Electrolyte disorders in oncological patients]. / Principaux troubles hydro-électrolytiques chez le patient de cancérologie.

Electrolyte disorders (ED) are common in patients with cancer and in most cases, the etiologies do not differ from the general population. They may also be induced by the cancer, its therapy or paraneoplastic syndromes. ED are associated with poor outcomes, increased morbidity and mortality in this population. Hyponatremia is the most common disorder, often multifactorial, iatrogenic or secondary to the syndrome of inappropriate antidiuretic hormone secretion, usually due to small cell lung cancer. More rarely, hyponatremia may reveal adrenal insufficiency. Hypokalemia is generally multifactorial and associated with other ED. Cisplatin and ifosfamide induce proximal tubulopathies with hypokalemia and/or hypophosphatemia. Hypomagnesemia is often iatrogenic, related to cisplatin or cetuximab, but can be prevented by supplementation. Hypercalcemia can impair life quality and be life-threatening in the most severe cases. Hypocalcemia is less common and often of iatrogenic origin. Finally, the tumor lysis syndrome is a diagnostic and therapeutic emergency that affects the prognosis of patients. Its incidence tends to increase in solid oncology, related to the improvement of therapies. Prevention and early diagnosis of ED are essential to optimize the overall management of patients with underlying cancer and cancer therapy. The aim of this review is to synthesize most frequent ED and their management.

Immune-related generalised oedema - A new category of adverse events with immune checkpoint inhibitors.

BACKGROUND: Generalised oedema was occasionally reported associated with immune checkpoint inhibitors (ICPIs). The purpose of this study is to investigate immune-related generalised oedema (ir-GE) drug related to ICPI, through frequency, clinical and pathological characteristics, and patient's outcome. PATIENTS AND METHODS: Objectives of the study were to report on ir-GE associated with ICPI to define frequency, associated signs and symptoms, pathological characteristics, severity, and response to corticosteroids. To be included in the study, adult patients had to have ir-GE related to ICPI with certain or likely link, without any other known causes of generalised oedema. The study design was observational, over the period 2014-2020, from pharmacovigilance databases in France, including the prospective Registre des Effets Indésirables Sévères des Anticorps Monoclonaux Immunomodulateurs en Cancérologie (REISAMIC) registry. Calculation of the frequency of ir-GE was restricted to the prospective REISAMIC registry. RESULTS: Over 6633 screened patients, 20 had ir-GE confirmed drug related to ICPI. Based on the prospective REISAMIC registry, the frequency of ir-GE was 0.19% of ICPI-treated patients (3 cases out of 1598 screened patients). The 20 patients with ir-GE had a median (range) age of 62 (26-81) years, most frequent tumour types were melanoma (n = 9; 45%) and lung cancer (n = 6; 30%). The most frequent localisations of oedema were peripheral (n = 17; 85%), pleural (n = 13; 65%), and peritoneal (n = 10; 50%). Polyserositis was observed in 11 (55%) patients. The median (range) weight gain per patient was 9 (2-30) kg. Associated signs and symptoms met criteria for capillary leak syndrome (n = 4; 20%), sinusoidal obstruction syndrome/veno-occlusive disease (SOS/VOD) (n = 3; 15%), or subcutaneous autoimmune syndrome (n = 2; 10%). Corticosteroids were administered to 15 patients; of them, 10 (67%) improved clinically after corticosteroids. Based on CTCAEV5.0, the highest severity of ir-GE was grade ≥4 in 11 (55%) patients and four (20%) patients died due to ir-GE. CONCLUSIONS: Generalised immune system-related oedema is a new category of adverse event with immune checkpoint inhibitors and is often associated with a life-threatening condition. The pathophysiology may in some cases be related to endothelial dysfunctions, such as SOS/VOD or capillary leak syndrome.

Prevalence and outcome of steroid-resistant/refractory pneumonitis induced by immune checkpoint inhibitors.

BACKGROUND: Anticancer immune-checkpoint inhibitors (ICI) can cause immune-related adverse events (irAEs), including interstitial pneumonitis, which is managed chiefly with systemic corticosteroids. When corticosteroids fail, second-line immunosuppressive therapy is indicated. Our objective was to evaluate the prevalence and outcomes of ICI-induced pneumonitis requiring second-line immunosuppressive therapy (IS). METHODS: We collected data form the REISAMIC pharmacovigilance registry and the multidisciplinary immunological toxicity board at Gustave Roussy (France). No response to steroids was called steroid-refractory pneumonitis and relapse after an initial response was defined as steroid-resistant pneumonitis. RESULTS: Of the 1187 patients screened from the REISAMIC register, 48 (4%) patients had pneumonitis treated with corticosteroids. Five of them (10%) had corticosteroid refractory/resistant disease but only 2 were treated with immunosuppressive therapy. Four additional patients requiring immunosuppressive therapy identified via the immunological toxicity board were included. Immunosuppressive therapy were cyclophosphamide (n=4 pts), infliximab (n=1 pt), intravenous immunoglobulins (n=1 pt). Five of these six patients had corticosteroid-refractory disease and one had corticosteroid-resistant pneumonitis. Five patients had severe pneumonitis (Common Terminology Criteria for Adverse Events grade ≥3) at initial pneumonitis diagnosis. Two months mortality rate in patients treated with IS was 67% (4/6). Among the patients treated with IS, the two patients alive at 5 months were treated with cyclophosphamide. CONCLUSION: Patients with ICI-pneumonitis treated by steroids received IS in 10% of cases. High mortality at 67% of patients was observed in ICI-pneumonitis after steroid failure. Cyclophosphamide could be a treatment option for pneumonitis after corticosteroid failure that requires further investigations.

The Polarity and Specificity of Antiviral T Lymphocyte Responses Determine Susceptibility to SARS-CoV-2 Infection in Patients with Cancer and Healthy Individuals.

Vaccination against coronavirus disease 2019 (COVID-19) relies on the in-depth understanding of protective immune responses to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). We characterized the polarity and specificity of memory T cells directed against SARS-CoV-2 viral lysates and peptides to determine correlates with spontaneous, virus-elicited, or vaccine-induced protection against COVID-19 in disease-free and cancer-bearing individuals. A disbalance between type 1 and 2 cytokine release was associated with high susceptibility to COVID-19. Individuals susceptible to infection exhibited a specific deficit in the T helper 1/T cytotoxic 1 (Th1/Tc1) peptide repertoire affecting the receptor binding domain of the spike protein (S1-RBD), a hotspot of viral mutations. Current vaccines triggered Th1/Tc1 responses in only a fraction of all subject categories, more effectively against the original sequence of S1-RBD than that from viral variants. We speculate that the next generation of vaccines should elicit Th1/Tc1 T-cell responses against the S1-RBD domain of emerging viral variants. SIGNIFICANCE: This study prospectively analyzed virus-specific T-cell correlates of protection against COVID-19 in healthy and cancer-bearing individuals. A disbalance between Th1/Th2 recall responses conferred susceptibility to COVID-19 in both populations, coinciding with selective defects in Th1 recognition of the receptor binding domain of spike. See related commentary by McGary and Vardhana, p. 892. This article is highlighted in the In This Issue feature, p. 873.

Anti-programmed death ligand 1 immunotherapies in cancer patients with pre-existing systemic sclerosis: A postmarketed phase IV safety assessment study.

OBJECTIVES: Cancer patients with pre-existing autoimmune disease, such as systemic sclerosis (SSc), are excluded from clinical trials, so the data on tolerability and efficacy of immune checkpoint inhibitors in these patients are limited. This study investigated the tolerability and efficacy of anti-programmed death ligand 1 (PD (L)1) immunotherapies in patients with pre-existing SSc. METHODS: Scleronco-01 was a multicentre, nationwide, open-label, phase IV observational study, from 2019 to 2021. RESULTS: Seventeen SSc patients receiving treatment for lung carcinoma (n = 13, 77%), head and neck cancer (n = 2, 12%), melanoma (n = 1, 6%), and colorectal carcinoma (n = 1, 6%) were included. The median (interquartile range) patient age was 60 (34-82) years. Fifteen (88%) patients received anti-PD1 (nivolumab and pembrolizumab) and two (12%) anti-PD-L1 (durvalumab). The median follow-up duration was 12 (range, 2-38) months. Four patients (24%) experienced flare-up of SSc symptoms. Ten patients (59%) developed an immune-related adverse event (grade I-II in 11 patients [65%], grade III-IV in one [6%]) without grade V. The overall response rate was 41% (7/17 patients). The median overall survival was 15.8 (95% confidence interval: 7.3 to not reached) months. CONCLUSION: Anti-PD1 or PD-L1 immunotherapies are suitable options for cancer patients with pre-existing SSc. Longer follow-up periods are required for long-term safety analyses.

The determinants of very severe immune-related adverse events associated with immune checkpoint inhibitors: A prospective study of the French REISAMIC registry.

BACKGROUND: Immune-related adverse events (irAEs) remain generally unpredictable, and severe irAEs remain challenging to detect early and manage. Very severe (grade IV-V) irAEs have not been extensively characterised in prospective studies, and their predictive factors remain unknown. OBJECTIVE: The objective of the study was to describe and identify predictive factors of very severe (grade IV-V) irAEs. DESIGN: The French Registre des Effets Indésirables Sévères des Anticorps Monoclonaux Immunomodulateurs en Cancérologie (REISAMIC) registry has prospectively collected all clinically significant irAEs occurring in patients treated with immune checkpoint inhibitors at Gustave Roussy Institute since 2014. SETTING: This was a single-centre prospective cohort study at the Gustave Roussy Institute cancer centre (Villejuif, France). PARTICIPANTS: The participants were all adult patients with a solid or haematological cancer treated with an anti-programmed cell death 1 (PD-1) or an anti-programmed cell death-ligand 1 (PD-L1) and who presented a clinically significant irAE. MAIN OUTCOMES AND MEASURES: The main outcomes included the clinical and laboratory characteristics of patients with very severe irAEs, including tumour type, affected organs, time to irAE occurrence, blood cell count and serum biochemistry parameters. RESULTS: Of the 1187 patients prospectively followed in REISAMIC between December 2014 and January 2020, 380 (32.0%) had at least one irAE, and 34 (2.86%) presented with very severe irAEs (grades IV-V). Among the 380 patients with an irAE, the distribution of very severe irAEs (grades IV-V) was 8.95% and death (grade V) was 3.95%. Among the 34 patients with very severe irAEs, 33 were treated with monotherapy of PD-1 or PD-L1 inhibitors, and one patient was treated with a combination of PD-1 and cytotoxic T-lymphocyte-associated protein 4 inhibitors. The median time to occurrence was shorter for very severe irAEs (median [interquartile range]: 41 days [0-634] for grades IV-V; versus 91 days [0-1123] for grades I-III; p = 0.01680). On initiation of immunotherapy, the predictive factors for very severe irAEs were performance status ≥2, elevated neutrophil/lymphocyte ratio and treatment for lung cancer. CONCLUSIONS: Very severe (grade IV-V) immunological toxicities occurred earlier than mild severe toxicities. On initiation of immunotherapy, patients with poor performance status, elevated neutrophil/lymphocyte ratio and lung cancer are identified at risk of developing these very severe toxicities. These results could help to develop risk scores to identify patients at risk of developing severe toxicities.

Neurological complications induced by immune checkpoint inhibitors: a comprehensive descriptive case-series unravelling high risk of long-term sequelae.

Neurological immune-related adverse events are complications of programmed-cell death 1 or programmed-cell death 1 ligand immunotherapies that can be life threatening and often lead to anticancer immunotherapy withdrawal. Scant clinical data are available that integrate the clinical presentation, therapeutic management and long-term outcome. All consecutive adult patients treated by programmed-cell death 1 or programmed-cell death 1 ligand immunotherapies, given alone or in combination with other treatment, who experienced a neurological immune-related adverse event with a severity grade ≥2 in Paris Saclay-University hospitals were investigated from June 2014 to February 2019. The frequency of neurological immune-related adverse events was calculated from the prospective Registre des Effets Indésirables Sévères des Anticorps Monoclonaux Immunomodulateurs en Cancérologie cohort. Forty patients presenting with 51 distinct neurological immune-related adverse events were included. The prevalence of grade ≥2 neurological immune-related adverse events was estimated to be 1.22% in the Registre des Effets Indésirables Sévères des Anticorps Monoclonaux Immunomodulateurs en Cancérologie cohort. Among 40 patients with neurological immune-related adverse events, 65% received programmed-cell death 1 or programmed-cell death 1 ligand monotherapy and 35% received a combination of programmed-cell death 1 plus anti-CTLA4 (Common Terminology Criteria for Adverse Events). Clinical neurological presentations were peripheral (48%), central (35%), or mixed (18%). The severity of neurological immune-related adverse events was grade 2 for 14 (35%) and ≥grade 3 for 26 patients (65%). The mortality rate related to neurological immune-related adverse events was 8%. Corticosteroid treatment led to neurological recovery in 74%. Long-term follow-up highlighted that 53% of patients experienced long-term neurological sequelae. Five patients were rechallenged by programmed-cell death 1 monotherapy without recurrence of their neurological immune-related adverse event(s). Neurological immune-related adverse events induced by programmed-cell death 1 or programmed-cell death 1 ligand are rare but are severe with a mortality rate of 8% and long-term sequelae for 53% of patients. Corticosteroids should be started when neurological immunological complications are identified to avoid long-term sequelae.

Circulating acetylated polyamines correlate with Covid-19 severity in cancer patients.

Cancer patients are particularly susceptible to the development of severe Covid-19, prompting us to investigate the serum metabolome of 204 cancer patients enrolled in the ONCOVID trial. We previously described that the immunosuppressive tryptophan/kynurenine metabolite anthranilic acid correlates with poor prognosis in non-cancer patients. In cancer patients, we observed an elevation of anthranilic acid at baseline (without Covid-19 diagnosis) and no further increase with mild or severe Covid-19. We found that, in cancer patients, Covid-19 severity was associated with the depletion of two bacterial metabolites, indole-3-proprionate and 3-phenylproprionate, that both positively correlated with the levels of several inflammatory cytokines. Most importantly, we observed that the levels of acetylated polyamines (in particular N1-acetylspermidine, N1,N8-diacetylspermidine and N1,N12-diacetylspermine), alone or in aggregate, were elevated in severe Covid-19 cancer patients requiring hospitalization as compared to uninfected cancer patients or cancer patients with mild Covid-19. N1-acetylspermidine and N1,N8-diacetylspermidine were also increased in patients exhibiting prolonged viral shedding (>40 days). An abundant literature indicates that such acetylated polyamines increase in the serum from patients with cancer, cardiovascular disease or neurodegeneration, associated with poor prognosis. Our present work supports the contention that acetylated polyamines are associated with severe Covid-19, both in the general population and in patients with malignant disease. Severe Covid-19 is characterized by a specific metabolomic signature suggestive of the overactivation of spermine/spermidine N1-acetyl transferase-1 (SAT1), which catalyzes the first step of polyamine catabolism.

Absence of significant clinical benefit for a systematic routine creatine phosphokinase measurement in asymptomatic patients treated with anti-programmed death protein (ligand) 1 immune checkpoint inhibitor to screen cardiac or neuromuscular immune-related toxicities.

AIM: Despite unprecedented results of anti-programmed death protein (ligand) 1 (PD-(L)1) immune checkpoint inhibitor in the oncology's armamentarium, immune-related adverse events (irAEs) represent a therapeutic hurdle. Currently, there is no consensual recommendation on a routinely monitored biomarker to early detect irAE. Biological markers such as serum creatine phosphokinase (CPK) are commonly used to measure muscular tissue injury. The potential of routine serum CPK monitoring to predict cardiac or neuromuscular irAE in patients treated with immunotherapy remains unknown. METHODS: In this retrospective study between January 2016 and December 2018 at Gustave Roussy Cancer Campus, 1151 cancer patients treated with anti-PD-(L)1 immunotherapy were systematically monitored with serum CPK measurements before each immunotherapy cycle. We considered significant CPK increases according to Common Terminology Criteria for Adverse Events v5.0 (CTCAEV5) of grade ≥2 severity. Comparisons were performed in patients with immune-related CPK (ir-CPK) elevations symptomatic versus asymptomatic. RESULTS: Overall, 53 of 1151 (4.6%) patients showed a CPK increase. Elevations of CPK were deemed to be immunotherapy-related in 31 of 1151 (2.7%) patients. Among them, 12 of 31 (38.7%) patients experienced symptomatic cardiac or neuromuscular irAE, whereas the other 19 of 31 (61.3%) patients remained asymptomatic. In patients with symptomatic irAE, the mean ir-CPK level was higher compared with asymptomatic patients (1271 versus 771 UI/L, P value = 0.02). In the asymptomatic group, all patients experienced a spontaneous resolution of the ir-CPK increase, and none required medical intervention. CONCLUSION: Most patients with immune-related CPK increase remained asymptomatic. The CPK serum increase did not alter the clinical management of asymptomatic patients. The results of this study did not support a significant clinical interest for a systematic routine CPK monitoring in patients amenable to anti-PD-(L)1 immunotherapy.

Outcomes of patients with cancer and sarcoid-like granulomatosis associated with immune checkpoint inhibitors: A case-control study.

PURPOSE: Sarcoid-like granulomatosis (SLG) reaction caused by immunotherapy remains poorly understood. This study aims to investigate the outcome of patients with cancer and SLG associated with immunotherapy. PATIENTS AND METHODS: Between April 2016 and June 2020, 434 patients with immunological adverse events were screened from the ImmunoTOX assessment board of Gustave Roussy, an academic cancer centre in France. Among them, 28 patients had SLG associated with immunotherapy (SLG cohort) and 406 patients had other immunological adverse events (control cohort). Clinical characteristics and outcome of patients were compared from SLG and control cohort. RESULTS: The SLG cohort consisted of 28 patients, 14 women and 14 men, with the median (range) age of 56.5 (28.7-75.3) years. Patients in the SLG cohort with sarcoidosis were asymptomatic (only radiographical finding) in 13 (46.4%) cases; otherwise, the most frequent symptoms were dyspnoea in 8 (28.6%) patients and cough in 5 (17.8%) patients. The computerised tomography scan found sarcoidosis localisations in mediastinal or peri-hilar thoracic lymph nodes in 26 (92.9%) patients, and lung parenchymal involvement was found in 14 (50.0%) patients. The radiographic Scadding stages for sarcoidosis classification were distributed in stages 0, I, II, III and IV in 2 patients (7.1%), 13 patients (46.4%), 11 patients (39.3%), 1 patient (3.6%) and 1 patient (3.6%), respectively. Compared with patients with other immunological toxicities (cohort control), patients with sarcoidosis presented most frequently with melanoma (75.0% versus 21.9% of patients; p < 0.001) and more often received combined therapies of anti-programmed cell death 1 plus anti-cytotoxic T-lymphocyte antigen 4 protein (46.4% versus 12.6% of patients; p = 0.002). Patients with sarcoidosis had an improved overall survival (OS); the median OS was not reached in the SLG cohort and 40.4 months in the control cohort, hazard ratio = 0.232 (95% confidence interval: 0.086-0.630) (p = 0.002). CONCLUSION: Sarcoidosis-like reactions in patients receiving immunotherapy were reported as non-severe immunological reactions in most cases and were correlated with improved OS. SLG should not be misdiagnosed as tumour progression in patients receiving immunotherapy treatment for cancer.

[Management of adverse events associated with cancer immunotherapy]. / "Prise en charge des effets indésirables de l'immunothérapie des cancers".

"Management of adverse events associated with cancer immunotherapy.The role of anti-CTLA4 and anti-PD1/PD-L1 immunotherapies in the treatment of cancers is constantly evolving. Given the latest data on their use in combination with «conventional¼ treatments, their use should increase in the coming years, exposing a significant number of patients to immunomediated toxicities. By lifting the brakes of the immune system, these immune checkpoints blockers can induce prolonged anti-tumor responses and increase patient survival. These new immunotherapies also have a different toxicity profile compared to conventional anti-cancer treatments, known as immune-related adverse events (irAEs). They result from the activation of the immune system against normal tissues and can trigger autoimmune diseases. This singular profile of toxicity prompts us to modify our clinical practice: this is the topic of this review that will describe the different adverse events and their management."

"Prise en charge des effets indésirables de l'immunothérapie des cancers.La place des immunothérapies anti-CTLA4 et anti-PD1/PD-L1 dans le traitement des cancers est en constante évolution. Au regard des dernières données en combinaison avec des traitements « conventionnels ¼, leur utilisation devrait augmenter dans les années à venir, exposant un nombre significatif de patients à des toxicités immunomédiées. En levant les freins du système immunitaire, ces bloqueurs des points de contrôle du système immunitaire permettent d'induire des réponses antitumorales prolongées et d'augmenter la survie des patients. Ces nouvelles immunothérapies présentent également un profil de toxicité différent des traitements anticancéreux conventionnels, appelés effets indésirables liés à l'immunité. Ils résultent de l'activation du système immunitaire contre les tissus normaux de l'organisme et peuvent être à l'origine de manifestations auto-immunes. Ce profil singulier de toxicité nous pousse à modifier nos pratiques cliniques : c'est l'objet de cette revue qui fera le point sur les différents effets indésirables et leur prise en charge."

Evaluation of Readministration of Immune Checkpoint Inhibitors After Immune-Related Adverse Events in Patients With Cancer.

IMPORTANCE: Although immune checkpoint inhibitors (ICIs), such as anti-PD-1 (programmed cell death 1) or anti-PD-L1 (programmed cell death 1 ligand 1), have proved effective in treating many cancers, patients receiving ICIs may experience immune-related adverse events (irAEs). Little evidence exists on the safety of resuming these treatments after an irAE. OBJECTIVE: To investigate the safety of a rechallenge with anti-PD-1 or anti-PD-L1 immunotherapies after an irAE. DESIGN, SETTING, AND PARTICIPANTS: This cohort study of the safety of an ICI rechallenge involved consecutive adult patients (n = 93) who were referred to the ImmunoTOX assessment board at the Gustave Roussy cancer center in Villejuif, France, between August 1, 2015, and December 31, 2017. Data were analyzed from May 28 to November 25, 2018. MAIN OUTCOMES AND MEASURES: Incidence of a second irAE in patients who had a readministration of an anti-PD-1 or anti-PD-L1 inhibitor after an initial grade 2 or higher irAE. Characteristics of the patients and the irAEs were reviewed, and the primary end point was the rate of occurrence of second irAEs. RESULTS: A total of 93 patients were included, among whom 48 (52%) were female, and the median (range) age was 62.5 (33-85) years. The main cancer types or tumor sites were melanoma (31 [33%]), lung (15 [16%]), colorectal (8 [9%]), and lymphoma (8 [9%]). For the initial irAE, 43 grade 2 events (46%), 36 grade 3 events (39%), and 14 grade 4 events (15%) were found, presenting primarily as hepatitis (17 [18%]), skin toxic effect (14 [15%]), pneumonitis (13 [14%]), colitis (11 [12%]), or arthralgia (7 [7.5%]). Forty patients (43%) were rechallenged with the same anti-PD-1 or anti-PD-L1 agent. The rechallenged and non-rechallenged groups did not differ in terms of median (range) age (61 [34-84] years vs 63 [33-85] years; P = .37), time to initial irAE (5 [1-40] treatment cycles vs 3 [1-22] treatment cycles; P = .32), irAE severity (grade 2: 18 [47.5%] vs 27 [51%]; grades 3-4: 22 [52.5%] vs 26 [49%]; P = .70), or steroid use (17 [42.5%] vs 32 [60%]; P = .09). With a median follow-up period of 14 months, the same irAE or a different irAE occurred in 22 patients (55%). Shorter time to the initial irAE was linked to the occurrence of a second irAE (9 vs 15 weeks; P = .04). The second irAEs were not found to be more severe than the first. CONCLUSIONS AND RELEVANCE: The risk-reward ratio for an anti-PD-1 or anti-PD-L1 rechallenge appears to be acceptable, although these patients require close monitoring; further investigation into rechallenge conditions through a prospective clinical trial is needed.

The Frequencies of Immunosuppressive Cells in Adipose Tissue Differ in Human, Non-human Primate, and Mouse Models.

Although the metabolic properties of white adipose tissue have been extensively characterized, the tissue's immune properties are now attracting renewed interest. Early experiments in a mouse model suggested that white adipose tissue contains a high density of regulatory T cells (Tregs), and so it was assumed that all adipose tissue has an immunosuppressive profile-even though the investigation was limited to visceral body fat in relatively old male mice. This observation was also corroborated by high frequencies of other cell subsets with immunoregulatory properties, such as anti-inflammatory M2 macrophages, and regulatory B cells. Many studies have since evidenced the persistence of pathogens (trypanosomes, Mycobacterium tuberculosis, HIV, etc.) in adipose tissue. However, a recent report identified adipose tissue as a reservoir of memory T cells capable of protecting animals upon rechallenge. The immune potential of lean adipose tissue thus remains to be further investigated. Here, we compared the relative proportions of immune cells (and Tregs in particular) in lean adipose tissue collected from humans, a non-human primate (the cynomolgus macaque), and three mouse models. We demonstrated that the proportion of Foxp3+ Tregs in visceral adipose tissue was low in all models other than the C57Bl/6 mouse. These low values were not linked to correspondingly low proportions of effector cells because T lymphocytes (a main target of Treg suppression) were more frequent in cynomolgus macaques than in C57Bl/6 mice and (to a lesser extent) humans. In contrast, the proportions of macrophages and B cells were lower in cynomolgus macaques than in C57Bl/6 mice. We also observed a higher proportion of CD34+CD45- cells (which predominantly correspond to mesenchymal stem cells) in C57Bl/6 mouse and cynomolgus macaques than in humans and both for subcutaneous and visceral adipose tissues. Lastly, a microscopy analysis confirmed predominant proportion of adipocytes within adipose tissue, and highlighted a marked difference in adipocyte size among the three species studied. In conclusion, our study of lean, middle-aged, male individuals showed that the immune compartment of adipose tissue differed markedly in humans vs. mice, and suggesting the presence of a more inflammatory steady-state profile in humans than mice.