Infections associated with clozapine: a pharmacovigilance study using VigiBase®.

Introduction: Clozapine is primarily reserved for treatment-resistant schizophrenia due to safety concerns associated with its use. Infections have been reported with clozapine, which may lead to elevated serum levels of the drug. However, the existing literature on this topic is limited. Therefore, we conducted a study using VigiBase® to investigate the potential over-reporting of infections associated with clozapine, to explore the presence of dose-dependency, and to investigate the underlying mechanism. Methods: Disproportionality analyses were performed using VigiBase to assess the association between clozapine and all types of infections, the association between clozapine-associated infections and neutropenia, the association between clozapine-associated infections and agranulocytosis, the dose-effect relationship between clozapine and infections, and the interaction between clozapine and the main strong CYP450 inhibitors using reports carried out until 11 April 2023. Results: A statistically significant signal of infections was observed with clozapine, as indicated by an information component of 0.43 [95% CI: (0.41-0.45)]. The most commonly reported infections were respiratory and gastrointestinal in nature. Neutropenia showed weaker association with clozapine-associated reports of infections compared to other clozapine-associated reports [X2 (1, N = 204,073) = 454; p < 0.005], while agranulocytosis demonstrated a stronger association with clozapine-associated reports of infections [X2 (1, N = 204,073) = 56; p < 0.005]. No evidence of dose-dependency was observed. Among the 17 tested CYP inhibitors, significant drug-drug interactions were found with clarithromycin, metronidazole, valproic acid, lansoprazole, omeprazole, amiodarone, and esomeprazole. Discussion: Our study revealed a significant safety signal between clozapine use and infections, predominantly respiratory and gastrointestinal infections. The co-administration of clozapine with valproic acid or proton pump inhibitors may potentially contribute to an increased risk of infection. Further vigilance is warranted in clinical practice, and consideration of therapeutic drug monitoring of clozapine in cases involving concomitant use of these drugs or in the presence of infections may be beneficial.

Atrial Fibrillation Incidence Associated With Exposure to Anticancer Drugs Used as Monotherapy in Clinical Trials.

Background: The incidence of atrial fibrillation (AF) associated with anticancer drugs in cancer patients remains incompletely defined. Objectives: The primary outcome was the annualized incidence rate of AF reporting associated with exposure to 1 of 19 anticancer drugs used as monotherapy in clinical trials. The authors also report the annualized incidence rate of AF reported in the placebo arms of these trials. Methods: The authors systematically searched ClinicalTrials.gov for phase 2 and 3 cancer trials studying 19 different anticancer drugs of interest used as monotherapy, up to September 18, 2020. The authors performed a random-effects meta-analysis to compute summary AF annualized incidence rate with its 95% CI using log transformation and inverse variance weighting. Results: A total of 191 clinical trials (47.1% were randomized) of 16 anticancer drugs across 26,604 patients were included. Incidence rates could be calculated for 15 drugs administered singly as monotherapy. Summary annualized incidence rates of AF reporting associated with exposure to 1 of the 15 anticancer drugs used as monotherapy were derived; these ranged from 0.26 to 4.92 per 100 person-years. The 3 highest annualized incidence rates of AF reporting were found for ibrutinib 4.92 (95% CI: 2.91-8.31), clofarabine 2.38 (95% CI: 0.66-8.55), and ponatinib 2.35 (95% CI: 1.78-3.12) per 100 person-years. Summary annualized incidence rate of AF reporting in the placebo arms was 0.25 per 100 person-years (95% CI: 0.10-0.65). Conclusions: AF reporting is not a rare event associated with anticancer drugs in clinical trials. A systematic and standardized AF detection should be considered in oncological trials, particularly those studying anticancer drugs associated with high AF rates. (Incidence of atrial fibrillation associated with anticancer drugs exposure in monotherapy, A safety meta-analysis of phase 2 and 3 clinical trials; CRD42020223710).

Rhabdomyolysis with Co-Administration of Statins and Antiplatelet Therapies-Analysis of the WHO Pharmacovigilance Database.

PURPOSE: While statins and antiplatelet therapies are largely prescribed together worldwide, limited information is available on the safety of their association regarding rhabdomyolysis occurrence. We aimed to assess the reporting of rhabdomyolysis in patients treated with a combination of statin and antiplatelet therapy, compared to statin alone. METHODS: We used the World Health Organization pharmacovigilance database (VigiBase®) to compare the rhabdomyolysis reporting between statin (atorvastatin, fluvastatin, pravastatin, rosuvastatin, and simvastatin) plus antiplatelet therapy (acetylsalicylic acid, clopidogrel, prasugrel and ticagrelor) groups versus statin alone groups, for each statin and antiplatelet therapy. Study setting was restricted to patients aged 45 or older, including reports up until 1st September, 2021. We computed reporting Odds-Ratio (ROR) and their 95% confidence interval (CI) to quantify the disproportionality between groups, adjusted on age and sex. RESULTS: Among the 11,431,708 reports of adverse reactions, we extracted 9,489 cases of rhabdomyolysis in patients treated with statins, of whom 2,464 (26%) were also treated with antiplatelet therapy. The reporting of rhabdomyolysis was increased when ticagrelor was associated with atorvastatin (ROR 1.30 [1.02-1.65]) or rosuvastatin (ROR 1.90 [1.42-2.54]) compared to the respective statin alone but did not change when aspirin, clopidogrel or prasugrel were considered. CONCLUSION: Rhabdomyolysis reporting was increased when ticagrelor -but not other antiplatelet agents- was notified with the most prescribed statins in practice. This finding needs to be considered by physicians especially in high-risk patients.

Immune Checkpoint Inhibitor-Related Cytopenias: About 68 Cases from the French Pharmacovigilance Database.

Immune checkpoint inhibitor (ICI)-related cytopenias have been poorly described. This study aimed to further characterize ICI-related cytopenias, using the French pharmacovigilance database. All grade ≥ 2 hematological adverse drug reactions involving at least one ICI coded as suspected or interacting drug according to the World Health Organization criteria and reported up to 31 March 2022, were extracted from the French pharmacovigilance database. Patients were included if they experienced ICI-related grade ≥ 2 cytopenia. We included 68 patients (75 ICI-related cytopenias). Sixty-three percent were male, and the median age was 63.0 years. Seven patients (10.3%) had a previous history of autoimmune disease. Immune thrombocytopenia (ITP) and autoimmune hemolytic anemia (AIHA) were the most frequently reported (50.7% and 25.3%, respectively). The median time to onset of ICI-related cytopenias was 2 months. Nearly half were grade ≥ 4, and three patients died from bleeding complications of refractory ITP and from thromboembolic disease with active AIHA. Out of 61 evaluable responses, complete or partial remission was observed after conventional treatment in 72.1% of ICI-related cytopenias. Among the 10 patients with ICI resumption after grade ≥ 2 ICI-related cytopenia, three relapsed. ICI-related cytopenias are rare but potentially life-threatening. Further studies are needed to identify risk factors of ICI-related cytopenias.

Transverse Myelitis Following SARS-CoV-2 Vaccination: A Pharmacoepidemiological Study in the World Health Organization's Database.

BACKGROUND: Transverse myelitis (TM) has recently been associated by health authorities with Ad26.COV2.S (Janssen/Johnson & Johnson), one of the 5 US Food and Drug Administration (FDA) or European Medicines Agency (EMA) labeled severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) vaccines. It is unknown whether a similar association exists for the other FDA or EMA labeled SARS-CoV-2 vaccines (BNT162b2 [Pfizer/BioNTech], mRNA-1273 [Moderna], ChAdOx1nCov-19 [Oxford-AstraZeneca], and NVX-CoV2373 [Novavax]). This study aimed to evaluate the association between SARS-CoV-2 vaccine class and TM. METHODS: This observational, cross-sectional, pharmacovigilance cohort study examined individual case safety reports from VigiBase, the World Health Organization's pharmacovigilance database. We first conducted a disproportionality analysis with the information component (IC) using the reports of TM that occurred within 28 days following exposure to the FDA or EMA labeled SARS-CoV-2 vaccines, from December 1, 2020 (first adverse event related to a SARS-CoV-2 vaccine) to March 27, 2022. Second, we analyzed the clinical features of SARS-CoV-2 vaccine-associated TM cases reported in VigiBase. RESULTS: TM was significantly associated both with the messenger ribonucleic acid (mRNA)-based (n = 364; IC025  = 0.62) and vector-based (n = 136; IC025  = 0.52) SARS-CoV-2 vaccines that are authorized by the FDA or the EMA. CONCLUSIONS: Findings from this observational, cross-sectional pharmacovigilance study showed that mRNA-based and vector-based FDA/EMA labeled SARS-CoV-2 vaccines can be associated with TM. However, because TM remains a rare event, with a previously reported rate of 0.28 cases per 1 million vaccine doses, the risk-benefit ratio in favor of vaccination against SARS-CoV-2 virus remains unchallenged. Rather, this study suggests that clinicians should consider the diagnosis of TM in patients presenting with early signs of spinal cord dysfunction after SARS-CoV-2 vaccination. ANN NEUROL 2022;92:1080-1089.

General medicine and notification of adverse reactions: contributions of health insurance representatives / Cabinets de médecine générale et notification des effets indésirables médicamenteux : expertise d'un délégué de l'Assurance maladie

INTRODUCTION: In order to reduce the under-reporting of adverse drug reactions (ADR) in general practice, the Caen Normandie regional pharmacovigilance center (CRPV) has implemented a training program for the French health insurance representatives (DAM) of the Manche department in order to raise awareness among general practitioners (GPs) to ADR reporting. PURPOSE OF RESEARCH: During quarterly visits of DAM to GPs, the mode of operation and the value of pharmacovigilance reporting was presented. This pilot study presents the impact of these DAM visits to GPs in term of ADRs reporting quantification. RESULTS: Assessment of this first year showed a doubling of ADR reporting by GPs of the Manche department in 2019 compared to 2017 and 2018. This phenomenon was not found in the two control departments (departments of Calvados and Orne) where the information had not been issued. These ADRs first concerned drugs of the renin-angiotensin system, then psychotropic drugs and anti-infectives. These were cutaneous, then neurological and gastrointestinal ADRs, preferentially affecting women. CONCLUSIONS: This experimentation should continue on a larger scale. The longer-term evaluation of this tool also requires evaluating its relevance.

Introduction: Pour réduire la sous-notification des effets indésirables médicamenteux (EIM) en médecine générale, le centre régional de pharmacovigilance (CRPV) Caen Normandie a mis en place une formation pour les délégués de la Caisse primaire d'assurance maladie de la Manche (CPAM 50) afin de sensibiliser les médecins généralistes (MG) à la déclaration des EIM. Ainsi, lors de la visite trimestrielle des délégués de la CPAM 50 aux MG, il était présenté le mode de fonctionnement et l'intérêt des déclarations de pharmacovigilance. But de l'étude: Cette étude pilote présente l'influence de ces visites post-formation des délégués de la CPAM 50 sur le nombre d'EIM déclarés. Résultats: Le bilan de cette première année de visites montre le doublement des EIM déclarés par les MG du département de la Manche en 2019 par rapport aux années 2017 et 2018. Ce phénomène n'a pas été retrouvé dans les deux départements témoins (départements du Calvados et de l'Orne), où l'information n'avait pas été délivrée. Ces EIM concernaient d'abord les médicaments du système rénine-angiotensine, puis les psychotropes et les anti-infectieux. Il s'agissait d'EIM cutanés puis neurologiques et gastro-intestinaux touchant préférentiellement les femmes. Conclusions: Cette expérimentation devra se poursuivre à plus large échelle. L'évaluation à plus long terme de ce dispositif permettra aussi d'en évaluer la pertinence.

Cardiovascular immunotoxicities associated with immune checkpoint inhibitors: a safety meta-analysis.

AIMS: The risk and incidence of cardiovascular (CV) immune-related adverse events (irAEs) associated with immune checkpoint inhibitors (ICIs) in cancer patients remain unknown. METHODS AND RESULTS: We systematically reviewed all randomized clinical trials (RCTs) including at least one ICI-containing arm and available CV adverse event (CVAE) data in cancer patients in the ClinicalTrials.gov registry, Medline, and the Cochrane CENTRAL Register of Controlled Trials, up to 31 August 2020 (CRD42020165672). The primary outcome was the summary risk of 16 different CVAEs associated with ICI exposure vs. controls (placebo and non-placebo) in RCTs. CVAEs with an increased risk associated with ICI exposure were considered as CV irAEs. Summary incidences of CV irAEs identified in our primary outcome analyses were computed using all RCTs including at least one ICI-containing arm. We used a random-effects meta-analysis to obtain Peto odds ratios (ORs) with 95% confidence intervals (CIs) and logit transformation and inverse variance weighting to compute summary incidences. Sixty-three unique RCTs with at least one ICI-containing arm (32 518 patients) were retrieved, among which 48 (29 592 patients) had a control arm. Among the 16 CVAEs studied, ICI use was associated with an increased risk of 6 CV irAEs including myocarditis, pericardial diseases, heart failure, dyslipidemia, myocardial infarction, and cerebral arterial ischaemia with higher risks for myocarditis (Peto OR: 4.42, 95% CI: 1.56-12.50, P < 0.01; I2 = 0%, P = 0.93) and dyslipidemia (Peto OR: 3.68, 95% CI: 1.89-7.19, P < 0.01; I2 = 0%, P = 0.66). The incidence of these CVAEs ranged from 3.2 (95% CI 2.0-5.1) to 19.3 (6.7-54.1) per 1000 patients, in studies with a median follow-up ranging from 3.2 to 32.8 months. CONCLUSION: In RCTs, ICI use was associated with six CV irAEs, not confined to myocarditis and pericarditis.

Characteristics of insulinopenic and non insulinopenic diabetes related to immune checkpoint inhibitors: A French pharmacovigilance study.

INTRODUCTION: Immune checkpoint inhibitor-induced diabetes mellitus (ICI-DM) is an immune-related adverse drug reaction (irADR). Hyperglycemia can be linked to endogenous insulin deficiency with ketoacidosis or associated with preserved beta-cell function. OBJECTIVES: We aimed to identify the characteristics of both types of ICI-DM (type 1 and type 2 DM), to improve our understanding of this irADR and its management. METHODS: Data for ICI-DM recorded in the French Pharmacovigilance Database from 2015 to October 2019 were analyzed according to the French causality assessment. RESULTS: In total, 60 subjects were included. Anti-PD1/PDL1 pathway blockade therapy (nivolumab: 61.7%+3.3% in association with ipilimumab pembrolizumab: 28.3%) was most frequently implicated in ICI-DM, but some reports involved anti-CTLA4 drug (ipilimumab: 6.7%+3.3% in association with nivolumab). One third of reports occurred within one month of the initiation of immunotherapy. Decreased insulin secretion (defined by the presence of ketone bodies) were confirmed in 80% of reports. Among them, 54% of patients met the diagnostic criteria for fulminant diabetes. Overall, 17.7% of the reports had pre-existing type 2 diabetes T2D. Four deaths due to hyperglycemia were declared, with altered insulin secretion in only two of these reports. BMI was lower in the insulinopenic group (23.4±0.7 vs. 27.9±1.6, P=0.004) and other irADRs were more frequently observed in patients with persistent insulin secretion (66.7 vs. 18.8%, P=0.02). We found no difference in age, indication or cumulative ICI dose between the two groups (with and without insulinopenia). The presence of GAD antibodies was associated with a shorter time to diabetes onset (42.6±6.1 vs. 208.1±41.6 days, P=0.029). CONCLUSIONS: ICI-DM is a rare but serious irADR triggered by all classes of immunotherapy. The observation period for ICI-DM can be shortened for patients positive for anti-GAD antibodies. Endogenous insulin deficiency did not appear to be the only mechanism involved in ICI-DM, as beta-cell function was preserved in 20% of reports. Improvements in our understanding of this complication will be required for its prevention.

[Adverse drug reactions profiles for abiraterone and enzalutamide: A pharmacovigilance descriptive analysis]. / Profils d'effets indésirables sous abiratérone et enzalutamide : analyse descriptive des données de la base nationale de pharmacovigilance.

OBJECTIVE: The aim of this study was to describe the profile of adverse drug reactions (ADRs) observed with abiraterone and enzalutamide, based on cases registered in the French regional pharmacovigilance centres to identify potential pharmacovigilance signals. METHODS: We extracted from the French pharmacovigilance database all cases of ADRs or drug interactions involving abiraterone or enzalutamide from the time they market authorization date until December 31st, 2017. Signal detection results have been transmitted by the French Agency for Health Products (ANSM). The data were compared with those of the risk management plans for each drug and the literature. RESULTS: Among the 233 observations analyzed, nearly 62% involved abiraterone as a suspect drug and 38% involved enzalutamide; only 1 case involved both drugs. The ADRs profile is different between the drugs. Abiraterone is mostly associated with expected cardiac diseases (heart failure, and QT prolongation), expected with the drug. Also described, several cases of hepatotoxicity have been reported, however some cases with fatal outcome suggest that despite a follow-up of the liver function tests, it is difficult to anticipate this risk. Signals concerning acute renal failure and ischemic stroke have arisen. Enzalutamide is more particularly associated with various neurological disorders (convulsions, hallucinations, fatigue, and memory impairment) expected with the drug. While ischemic heart disease is also expected, signals of heart failure and atrial fibrillation have arisen. A potential hepatotoxicity of the molecule is discussed because of cases of cholestatic hepatitis. CONCLUSION: The analysis of the French pharmacovigilance database cases allows to confirm an expected and monitored risk profile in the risk management plan for both drugs. Several signals have arisen, some of which will be investigated through a pharmacoepidemiology study.

Disproportionality analysis in VigiBase as a drug repositioning method for the discovery of potentially useful drugs in Alzheimer's disease.

Drug repositioning aims to propose new indications for marketed drugs. Although several methods exist, the utility of pharmacovigilance databases for this purpose is unclear. We conducted a disproportionality analysis in the World Health Organization pharmacovigilance database VigiBase to identify potential anticholinesterase drug candidates for repositioning in Alzheimer's disease (AD). METHODS: Disproportionality analysis is a validated method for detecting significant associations between drugs and adverse events (AEs) in pharmacovigilance databases. We applied this approach in VigiBase to establish the safety profile displayed by the anticholinesterase drugs used in AD and searched the database for drugs with similar safety profiles. The detected drugs with potential activity against acetylcholinesterase and butyrylcholinesterases (BuChEs) were then evaluated to confirm their anticholinesterase potential. RESULTS: We identified 22 drugs with safety profiles similar to AD medicines. Among these drugs, 4 (clozapine, aripiprazole, sertraline and S-duloxetine) showed a human BuChE inhibition rate of over 70% at 10-5  M. Their human BuChE half maximal inhibitory concentration values were compatible with clinical anticholinesterase action in humans at their normal doses. The most active human BuChE inhibitor in our study was S-duloxetine, with a half maximal inhibitory concentration of 1.2 µM. Combined with its ability to inhibit serotonin (5-HT) reuptake, the use of this drug could represent a novel multitarget directed ligand therapeutic strategy for AD. CONCLUSION: We identified 4 drugs with repositioning potential in AD using drug safety profiles derived from a pharmacovigilance database. This method could be useful for future drug repositioning efforts.

Haematologic malignancies associated with clozapine v. all other antipsychotic agents: a pharmacovigilance study in VigiBase®.

BACKGROUND: Clozapine is mainly used in patients with treatment-resistant schizophrenia and may lead to potentially severe haematologic adverse events, such as agranulocytosis. Whether clozapine might be associated with haematologic malignancies is unknown. We aimed to assess the association between haematologic malignancies and clozapine using Vigibase®, the WHO pharmacovigilance database. METHODS: We performed a disproportionality analysis to compute reporting odds-ratio adjusted for age, sex and concurrent reporting of antineoplastic/immunomodulating agents (aROR) for clozapine and structurally related drugs (loxapine, olanzapine and quetiapine) compared with other antipsychotic drugs. Cases were malignant lymphoma and leukaemia reports. Non-cases were all other reports including at least one antipsychotic report. RESULTS: Of the 140 226 clozapine-associated reports, 493 were malignant lymphoma cases, and 275 were leukaemia cases. Clozapine was significantly associated with malignant lymphoma (aROR 9.14, 95% CI 7.75-10.77) and leukaemia (aROR 3.54, 95% CI 2.97-4.22). Patients suffering from those haematologic malignancies were significantly younger in the clozapine treatment group than patients treated with other medicines (p < 0.001). The median time to onset (available for 212 cases) was 5.1 years (IQR 2.2-9.9) for malignant lymphoma and 2.5 years (IQR 0.6-7.4) for leukaemia. The aROR by quartile of dose of clozapine in patients with haematologic malignancies suggested a dose-dependent association. CONCLUSIONS: Clozapine was significantly associated with a pharmacovigilance signal of haematologic malignancies. The risk-benefit balance of clozapine should be carefully assessed in patients with risk factors of haematologic malignancies. Clozapine should be used at the lowest effective posology.

Association Between Use of Anticancer Drugs and Cardiovascular Disease-Related Hospitalization in Metastatic Colorectal Cancer: Insights From a Population-Based Study, the Anticancer Vigilance of Cardiac Events Study.

We aimed to investigate the association between use of anticancer drugs and cardiovascular-related hospitalization (CVRH) among patients with metastatic colorectal cancer (mCRC). A cohort study, the Anticancer Vigilance of Cardiac Events (AVOCETTE) Study, was conducted using data from the digestive tumor registry of a French county, the Département du Calvados. Incident mCRC cases diagnosed between 2008 and 2014 were included. The follow-up end date was December 31, 2016. Data from the county hospital center pharmacy and medical information departments were matched with the registry data. A competing-risks approach was used. Statistical tests were 2-sided. A total of 1,116 mCRC patients were included, and they were administered 12,374 rounds of treatment; fluorouracil, oxaliplatin, irinotecan, and bevacizumab were most common drugs used. A total of 208 CVRH events occurred in 145 patients (13.0%). The International Cancer Survival Standards type 1 standardized incidence was 84.0 CVRH per 1,000 person-years (95% confidence interval: 72.6, 95.5). Anticancer drugs were not associated with a higher incidence of CVRH. Male sex, increasing age, a prior history of CVRH, and a higher Charlson comorbidity index score were associated with a higher incidence of CVRH. CVRH was significantly associated with higher all-cause mortality (multivariable hazard ratio = 1.58, 95% confidence interval: 1.28, 1.95). In this study, anticancer drugs were not associated with a higher incidence of CVRH in mCRC patients.

Identification of anticancer drugs associated with atrial fibrillation: analysis of the WHO pharmacovigilance database.

AIMS: The explosion of novel anticancer therapies has meant emergence of cardiotoxicity signals including atrial fibrillation (AF). Reliable data concerning the liability of anticancer drugs in inducing AF are scarce. Using the World Health Organization individual case safety report database, VigiBase®, we aimed to determine the association between anticancer drugs and AF. METHODS AND RESULTS: A disproportionality analysis evaluating the multivariable-adjusted reporting odds ratios for AF with their 99.97% confidence intervals was performed for 176 U.S. Food and Drug Administration (FDA)- or European Medicines Agency (EMA)-labelled anticancer drugs in VigiBase®, followed by a descriptive analysis of AF cases for the anticancer drugs identified in VigiBase®. ClinicalTrial registration number: NCT03530215. A total of 11 757 AF cases associated with at least one anticancer drug were identified in VigiBase® of which 95.8% were deemed serious. Nineteen anticancer drugs were significantly associated with AF of which 14 (74%) are used in haematologic malignancies and 9 (45%) represented new AF associations not previously confirmed in literature including immunomodulating agents (lenalidomide, pomalidomide), several kinase inhibitors (nilotinib, ponatinib, midostaurin), antimetabolites (azacytidine, clofarabine), docetaxel (taxane), and obinutuzumab, an anti-CD20 monoclonal antibody. CONCLUSION: Although cancer malignancy itself may generate AF, we identified 19 anticancer drugs significantly associated with a significant increase in AF over-reporting. This pharmacovigilance study provides evidence that anticancer drugs themselves could represent independent risk factors for AF development. Dedicated prospective clinical trials are now required to confirm these 19 associations. This list of suspected anticancer drugs should be known by physicians when confronted to AF in cancer patients, particularly in case of haematologic malignancies.

Could N-acetylcysteine improve the safety of clozapine?

Clozapine is an atypical antipsychotic indicated in patients with treatment-resistant schizophrenia which remains underused due to safety issues. Mechanisms behind these adverse effects are complex and not fully understood. They may involve immune-related mechanisms, direct toxic effects and oxidative stress. Clozapine-induced oxidative stress might indeed notably be involved in the onset of neutropenia, agranulocytosis, myocarditis, sialorrhea, and metabolic alterations. Therefore, the association of N-acetylcysteine (NAC), an easily accessible, low-cost and well tolerated antioxidant drug could be of interest in clozapine-treated patients to improve clozapine safety. Furthermore, according to recent studies NAC could help to improve schizophrenia symptoms. We believe that the use of NAC in the context of clozapine prescribing merits further study, as it could improve clozapine safety which may lead to a wider use and ultimately improve the healthcare of thousands of patients. NAC could also secondarily show positive knock-on effects for the patients by improving clinical symptoms of schizophrenia in synergy with clozapine, and by reducing substance abuse and thus by improving the patient's overall condition. However, given the rarity of clozapine-induced severe adverse effects, only a large volume of data (e.g., National adverse events monitoring) could assess the benefits of NAC on clozapine safety.

Cardiovascular safety of rapidly accelerated fibrosarcoma B-type and/or mitogen-activated extracellular signal-regulated kinase inhibitors: A mixed approach combining a meta-analysis and a pharmacovigilance disproportionality analysis.

BACKGROUND: The risk of cardiovascular adverse events from rapidly accelerated fibrosarcoma B-type (BRAF) and mitogen-activated extracellular signal-regulated kinase (MEK) inhibitors is not fully characterized. AIM: To evaluate the cardiovascular adverse events risks related to BRAF and/or MEK inhibitors in randomized placebo-controlled clinical trials and in the real-life setting. METHODS: We used two approaches. First, we conducted a systematic review and meta-analysis of randomized placebo-controlled clinical trials reporting the incidence of cardiovascular adverse events for BRAF and/or MEK inhibitors in cancer patients. Second, we performed a disproportionality analysis, using age- and sex-adjusted reporting odds ratios (arORs) and their 95% confidence intervals (CIs) from the World Health Organization's pharmacovigilance database (VigiBase®) of anticancer drug-associated reports, to investigate real-life data. RESULTS: MEK inhibitors increased the risk of ejection fraction decrease (odds ratio [OR] 3.35, 95% CI 1.58-7.07), peripheral oedema (OR 2.87 95% CI 1.93-4.27) and syncope (OR 6.71, 95% CI 3.00-14.99) compared with placebo in randomized placebo-controlled clinical trials. BRAF and MEK inhibitor combination therapy further increased the risk of ejection fraction decrease. In the disproportionality analysis, we found over-reporting of ejection fraction decrease (arOR 8.42, 95% CI 7.03-10.09), peripheral oedema (arOR 1.39, 95% CI 1.17-1.66), syncope (arOR 1.56, 95% CI 1.22-1.99), torsade de pointes/QT prolongation (arOR 6.13, 95% CI 5.04-7.47) and supraventricular arrhythmias (arOR 1.50, 95% CI 1.21-1.85) for BRAF and MEK inhibitors. BRAF and MEK inhibitors were not associated with hypertension in either approach. CONCLUSIONS: In conclusion, MEK inhibitors increase the risk of ejection fraction decrease, peripheral oedema and syncope in randomized placebo-controlled clinical trials. Real-life data confirm these findings, and suggested additional risks of torsade de pointes/QT prolongation and supraventricular arrhythmias with BRAF/MEK inhibitors.

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

Importance: Limited information is available on the safety of a rechallenge with an immune checkpoint inhibitor (ICI) after an immune-related adverse event (irAE). Objective: To identify the recurrence rate of the same irAE that prompted discontinuation of ICI therapy after an ICI rechallenge in patients with cancer and to identify the clinical features associated with such recurrences. Design, Setting, and Participants: This observational, cross-sectional, pharmacovigilance cohort study examined individual case safety reports from the World Health Organization database VigiBase, which contains case reports from more than 130 countries. Case reports were extracted from database inception (1967) to September 1, 2019. All consecutive ICI cases with at least 1 associated irAE were included. Main Outcomes and Measures: The primary outcome was the rate of recurrence of the initial irAE after an ICI rechallenge. Secondary outcomes included the factors associated with the recurrence after a rechallenge among informative rechallenges, the recurrence rate according to the ICI regimen (anti-programmed cell death 1 or anti-programmed cell death ligand 1 monotherapy, anti-cytotoxic T-lymphocyte antigen-4 monotherapy, or combination therapy), and the rate of occurrence of a different irAE after a rechallenge. Results: A total of 24 079 irAE cases associated with at least 1 ICI were identified. Among the irAEs, 452 of 6123 irAEs associated with ICI rechallenges (7.4%) were informative rechallenges. One hundred thirty recurrences (28.8%; 95% CI, 24.8-33.1) of the initial irAE were observed. In a rechallenge, colitis (reporting odds ratio [OR], 1.77; 95% CI, 1.14-2.75; P = .01), hepatitis (reporting OR, 3.38; 95% CI, 1.31-8.74; P = .01), and pneumonitis (reporting OR, 2.26; 95% CI, 1.18-4.32; P = .01) were associated with a higher recurrence rate, whereas adrenal events were associated with a lower recurrence rate (reporting OR, 0.33; 95% CI, 0.13-0.86; P = .03) compared with other irAEs. Conclusions and Relevance: This cohort study found a 28.8% recurrence rate of the same irAE associated with the discontinuation of ICI therapy after a rechallenge with the same ICI. Resuming ICI therapy could be considered for select patients, with appropriate monitoring and use of standard treatment algorithms to identify and treat toxic effects.