Comparing pulsed field electroporation and radiofrequency ablation for the treatment of paroxysmal atrial fibrillation: design and rationale of the BEAT PAROX-AF randomized clinical trial.

AIMS: Using thermal-based energy sources [radiofrequency (RF) energy/cryo energy] for catheter ablation is considered effective and safe when performing pulmonary vein isolation (PVI) in patients with paroxysmal atrial fibrillation (AF). However, treatment success remains limited and complications can occur due to the propagation of thermal energy into non-target tissues. We aim to compare pulsed field ablation (PFA) with RF ablation in terms of efficacy and safety for patients with drug-resistant paroxysmal AF. METHODS AND RESULTS: The BEAT PAROX-AF trial is a European multicentre, superiority, open-label randomized clinical trial in two parallel groups. A total of 292 participants were recruited in 9 high-volume European clinical centres in 5 countries. Patients with paroxysmal AF were randomized to PFA (FARAPULSE Endocardial Ablation System©, Boston Scientific) or RF using the CLOSE protocol with contact force sensing catheter (SmartTouch© catheter and CARTO© Biosense Webster). The primary endpoint will be the 1-year recurrence of atrial arrhythmia, and the major secondary safety endpoint will be the occurrence of acute (<7 days) procedure-related serious adverse events, or pulmonary vein stenosis, or atrio-oesophageal fistula up to 12 months. Additionally, five sub-studies investigate the effect of PFA on oesophageal safety, cerebral lesions, cardiac autonomic nervous system, durability of PVI as assessed during redo ablation procedures, and atrial and ventricular function. The study began on 27 December 2021 and concluded recruitment on 17 January 2024. Results will be available in mid-2025. CONCLUSION: The BEAT PAROX-AF trial aims to provide critical insights into the optimal treatment approach for patients with paroxysmal AF.

Biomonitoring of occupational exposure to 5-FU by assaying α-fluoro-ß-alanine in urine with a highly sensitive UHPLC-MS/MS method.

5-Fluorouracil (5-FU) is one of the most widely used antineoplastic drugs handled by healthcare professionals (HCP). To monitor occupational exposure to 5-FU, a highly sensitive ESI-UHPLC-MS/MS method was developed for the assay of its main human metabolite, α-fluoro-ß-alanine (FBAL), in urine. After a derivatization step, solid phase extraction was used for the urine. Good linearity (r > 0.996), precision (CV < 14.76%), and accuracy (bias < 12.16%) were achieved. The lower limit of quantification (LOQ), 20 pg ml-1, is the lowest one published to date. Seven urine samples from 73 HCP exposed to 5FU were positive for FBAL, indicating 5FU contamination (9.6%). FBAL urine concentrations ranged from 25 to 301 pg ml-1. Such an efficient analytical tool combining high specificity with high sensitivity is essential for the reliable detection and routine biological monitoring of healthcare professionals occupationally exposed to this widely used antineoplastic drug. This method allows biomonitoring of occupational exposure to 5-fluorouracil in a routine manner, with the aim of assessing the effectiveness of collective and individual protective measures.

Immunotherapy-induced hypothyroidism A report of melanoma treated by ipilimumab and nivolumab.

We report the case of a patient treated by ipilimumab and nivolumab for a metastatic melanoma. After a mild clinical thyroiditis and a transient biological hyperthyroidism she rapidly demonstrated a peripheral hypothyroidism with appearance of antibodies against thyroperoxidase and thyroglobulin.

High throughput routine determination of 17 tyrosine kinase inhibitors by LC-MS/MS.

Several studies have shown that therapeutic drug monitoring of tyrosine kinase inhibitors (TKI) can improve their benefit in cancer. An analytical tool has been developed in order to quantify 17 tyrosine kinase inhibitors and 2 metabolites in human plasma (afatinib, axitinib, bosutinib, crizotinib, dabrafenib, dasatinib, erlotinib, gefitinib, imatinib, lapatinib, nilotinib, ponatinib, regorafenib, regorafenib M2, regorafenib M5, ruxolitinib, sorafenib, sunitinib, vandetanib). Drugs were arranged in four groups, according to their plasma concentration range: 0.1-200ng/ml, 1-200ng/ml, 4-800ng/ml and 25-5000ng/ml. Solid phase extraction was used and separation was performed with HPLC using a gradient system on a solid core particle C18 column (5×2.1mm, 1.6µm). Ions were detected with a triple quadrupole mass spectrometry system. This assay allows rapid determination of 19 TKI in less than 5min per run. This high throughput routine method will be useful to adjust doses of oral anticancer drugs in order to improve treatments efficacy.

Comparative Safety of Targeted Therapies for Metastatic Colorectal Cancer between Elderly and Younger Patients: a Study Using the International Pharmacovigilance Database.

BACKGROUND: Metastatic colorectal cancer (mCRC) is increasingly treated using targeted therapies. Post-marketing safety of these agents is understudied, especially in the elderly. OBJECTIVE: This study aimed to compare, according to age, the adverse drug reactions (ADRs) of targeted therapies used for mCRC in real life. PATIENTS AND METHODS: An extraction of VigiBase, which contains World Health Organization individual case safety reports (ICSRs), was performed. All ADR reports with aflibercept, bevacizumab, cetuximab, panitumumab, or regorafenib used in CRC were considered. For all drugs, chi-square tests were used to compare frequencies of serious ADRs between patients aged ≥75 and <75 years. For selected ADRs and each drug, the drug-ADR association compared to other anticancer drugs was estimated through the proportional reporting ratio (PRR) in both age groups. RESULTS: There were 21,565 ICSRs included, among which 74% were serious and 11% were fatal. Median age was 64 years (Inter Quartile Range = 56-71) and 15% of patients were aged ≥75; 57% were male. Serious ICSRs accounted for 47,292 ADRs. Neutropenia was not more reported in elderly for all drugs while diarrhea was more reported in elderly for panitumumab. Cardiac disorders were more reported in elderly patients, in particular heart failure, especially for bevacizumab, cetuximab, and regorafenib, as were respiratory, thoracic, and mediastinal disorders. Most of PRR were not different between the two groups, except encephalopathies, which were significantly associated with bevacizumab in the elderly only. CONCLUSIONS: ADRs related to targeted therapies used for mCRC treatment were different across age groups; yet, not systematically more reported or worse in elderly patients. Selected elderly patients could, therefore, be treated with these targeted therapies.

Trough dabrafenib plasma concentrations can predict occurrence of adverse events requiring dose reduction in metastatic melanoma.

INTRODUCTION: Dabrafenib and trametinib bitherapy provides significant benefits in BRAFV600mut metastatic melanoma patients; however, adverse events (AE) occur, leading to dose reduction in 33% of patients. We aimed to investigate a relation between plasma dabrafenib and trametinib concentrations and occurrence of AE. METHODS: Plasma samples from metastatic BRAFV600mut melanoma patients treated with dabrafenib±trametinib were prospectively collected at trough concentration before any dose reduction. Dabrafenib and trametinib were measured by UPLC-MS/MS. Plasma threshold of concentration associated with dose reduction for AE was studied by ROC-curve analysis. RESULTS: Twenty-seven patients (13M/14F) were included. Dabrafenib trough plasma concentrations displayed high interindividual variability, ranging from 15.4 to 279.6ng/ml, mean±SD 58.7±61.1ng/ml. Trough trametinib plasma concentrations ranged from 4.1 to 23.8ng/ml, mean±SD 11.9±4.1ng/ml. Mean trough dabrafenib plasma concentration was higher in patients with AE requiring dose reduction (30%) than in other patients: 118.6ng/ml and 33.5ng/ml respectively (P<0.0001). Adverse events leading to dabrafenib dose reduction were all grade≥2. No differences in mean trametinib trough plasma concentrations were observed in patients requiring or not dose reduction. A dabrafenib trough plasma threshold of 48ng/ml can predict the occurrence of adverse events requiring dose reduction.

An UPLC-MS/MS method for the quantification of BRAF inhibitors (vemurafenib, dabrafenib) and MEK inhibitors (cobimetinib, trametinib, binimetinib) in human plasma. Application to treated melanoma patients.

Targeted therapies for cancers are fast-growing therapies. For instance kinase inhibitors such as BRAF inhibitors (BRAFi) and MEK inhibitors (MEKi) are increasingly used to treat malignant melanoma. The metabolic profile of these drugs can result in great interindividual variability, justifying therapeutic drug monitoring (TDM). We describe a rapid and specific method for quantification of 2 BRAFi (vemurafenib, dabrafenib) and 3 MEKi (cobimetinib, trametinib and binimetinib). Chromatography was performed on a Waters Acquity-UPLC system with CORTECS C18+ column, under a gradient of 10% acetic acid in water/acetonitrile. An Acquity-TQD® with electrospray ionization was used for detection. Samples were prepared by solid phase extraction (Oasis® MCX microElution) before injection in the system. Calibration curves ranges from 0.4 to 100µg/ml for vemurafenib, from 1 to 1000ng/ml for dabrafenib, from 0.5 to 500ng/ml for cobimetinib and binimetinib, and from 0.75 to 250ng/ml for trametinib. At all concentrations the bias was within ±15% of the nominal concentrations and precision was ≤15%. All results were within the acceptance criteria of the EMA guidelines on method validation. This rapid, sensitive and specific UPLC-MS/MS method can perform simultaneous quantification of targeted therapies used in malignant melanoma and is usable for routine TDM.

Implication of oxidative stress in size-dependent toxicity of silica nanoparticles in kidney cells.

Silica nanoparticles (nano-SiO(2)) are one of the most popular nanomaterials used in industrial manufacturing, synthesis, engineering and medicine. While inhalation of nanoparticles causes pulmonary damage, nano-SiO(2) can be transported into the blood and deposit in target organs where they exert potential toxic effects. Kidney is considered as such a secondary target organ. However, toxicological information of their effect on renal cells and the mechanisms involved remain sparse. In the present study, the cytotoxicity of nano-SiO(2) of different sizes was investigated on two renal proximal tubular cell lines (human HK-2 and porcine LLC-PK(1)). The molecular pathways involved were studied with a focus on the involvement of oxidative stress. Nanoparticle characterization was performed (primary nanoparticle size, surface area, dispersion) in order to investigate a potential relationship between their physical properties and their toxic effects. Firstly, evidence of particle internalization was obtained by transmission electron microscopy and conventional flux cytometry techniques. The use of specific inhibitors of endocytosis pathways showed an internalization process by macropinocytosis and clathrin-mediated endocytosis for 100 nm nano-SiO(2) nanoparticles. These nanoparticles were localized in vesicles. Toxicity was size- and time-dependent (24h, 48 h, 72 h). Indeed, it increased as nanoparticles became smaller. Secondly, analysis of oxidative stress based on the assessment of ROS (reactive oxygen species) production (DHE, dihydroethidium) or lipid peroxidation (MDA, malondialdehyde) clearly demonstrated the involvement of oxidative stress in the toxicity of 20 nm nano-SiO(2). The induction of antioxidant enzymes (catalase, GSTpi, thioredoxin reductase) could explain their lesser toxicity with 100 nm nano-SiO(2).