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A liquid chromatography tandem mass spectrometry method for the analysis of ten kinase inhibitors (afatinib, axitinib, bosutinib, cabozantinib, dabrafenib, lenvatinib, nilotinib, osimertinib, ruxolitinib, and trametinib) in human serum and plasma for the application in daily clinical routine has been developed and validated according to the US Food and Drug Administration and European Medicines Agency validation guidelines for bioanalytical methods. After protein precipitation of plasma samples with acetonitrile, chromatographic separation was performed at ambient temperature using a Waters XBridge® Phenyl 3.5 μm (2.1 × 50 mm) column. The mobile phases consisted of water-methanol (9:1, v/v) with 10 mM ammonium bicarbonate as phase A and methanol-water (9:1, v/v) with 10 mM ammonium bicarbonate as phase B. Gradient elution was applied at a flow rate of 400 μL/min. Analytes were detected and quantified using multiple reaction monitoring in electrospray ionization positive mode. Stable isotopically labeled compounds of each kinase inhibitor were used as internal standards. The acquisition time was 7.0 min per run. All analytes and internal standards eluted within 3.0 min. The calibration curves were linear over the range of 2–500 ng/mL for afatinib, axitinib, bosutinib, lenvatinib, ruxolitinib, and trametinib, and 6–1500 ng/mL for cabozantinib, dabrafenib, nilotinib, and osimertinib (coefficients of correlation ≥ 0.99). Validation assays for accuracy and precision, matrix effect, recovery, carryover, and stability were appropriate according to regulatory agencies. The rapid and sensitive assay ensures high throughput and was successfully applied to monitor concentrations of kinase inhibitors in patients.

C hronic thromboembolic pulmonary hypertension (CTEPH)is an important but yet under-researched entity of PH. CTEPH is characterized by nonresolving thrombi that obstruct pulmonary arteries and promote progressive pulmonary vascular remodeling. The chronic increase in pulmonary vascular resistance translates into elevated pulmonary artery pressure and results in right ventricular (RV) hypertrophy, which ultimately causes RV dilatation and failure.2 The treatment of choice is pulmonary endarterectomy that consist in the surgical removal of organized thrombi to an extent that improves pulmonary hemodynamics. However, a relevant number of patients present persistent small-vessel vasculopathy post pulmonary endarterectomy , 3 and many affected individuals are poor candidates for pulmonary endarterectomy because of a predominantly distal surgically inaccessible embolism pattern, high age, or severe comorbidities. Therefore to improve quality of life and eventually survival, numerous CTEPH patients require additional or alternative nonsurgical treatment. However, our understanding of the pathophysiology of CTEPH is limited and an obstacle in the development of new treatment strategies. 4 The pathogenesis of CTEPH is still under debate. According to the local thrombosis hypothesis, CTEPH originates from primary distal pulmonary arteropathy accompanied by secondary in situ thrombosis. However, this hypothesis does not provide a mechanism to explain proximal pulmonary artery thrombosis.5 Thus, the majority of experts in the field favor the embolism hypothesis that attributes CTEPH pathogenesis to a single or recurrent pulmonary embolisms (PE). The latter hypothesis is supported by a history of PE in ≤75% of all CTEPH patients and by the beneficial effects of timely performed pulmonary endarterectomy. 2,6 Finally, several risk factors for CTEPH including specific procoagulation factors such as phospholipid antibodies, protein S and protein C, factor V mutations, malignancy, inflammatory bowel disease, and previous deep vein thrombosis are also risk factors for recurrent PE.6,7 It is not yet understood how PE progresses to CTEPH, and the mechanisms behind thrombi escape to thrombolysis and subsequent fibrotic transformation are still unknown. Consequently, there is a need for simple and reproducible CTEPH animal models that not only permit the analysis of molecular signals involved in the pathology of this disease but also enable the evaluation of new therapeutic strategies to improve the fate of individuals diagnosed with CTEPH.Abstract-Chronic thromboembolic pulmonary hypertension (CTEPH) is an entity of PH that not only limits patients quality of life but also causes significant morbidity and mortality. The treatment of choice is pulmonary endarterectomy. However numerous patients do not qualify for pulmonary endarterectomy or present with residual vasculopathy post pulmonary endarterectomy and require specific vasodilator treatment. Currently, there is no available specific small animal model of CTEPH that could serve a...

Pseudo-progression and flare-up phenomena constitute a novel diagnostic challenge in the follow-up of patients treated with immune-oncology drugs. We present a case study on pulmonary flare-up after Idecabtagen Vicleucel (Ide-cel), a BCMA targeting CAR T-cell therapy, and used single-cell RNA-seq (scRNA-seq) to identify a Th17.1 driven autoimmune mechanism as the biological underpinning of this phenomenon. By integrating datasets of various lung pathological conditions, we revealed transcriptomic similarities between post CAR T pulmonary lesions and sarcoidosis. Furthermore, we explored a noninvasive PET based diagnostic approach and showed that tracers binding to CXCR4 complement FDG PET imaging in this setting, allowing discrimination between immune-mediated changes and true relapse after CAR T-cell treatment. In conclusion, our study highlights a Th17.1 driven autoimmune phenomenon after CAR T, which may be misinterpreted as disease relapse, and that imaging with multiple PET tracers and scRNA-seq could help in this diagnostic dilemma.

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