Afatinib is an oral tyrosine kinase inhibitor (TKI) approved for treating advanced non-small cell lung cancer. It is necessary to develop a simple quantification method for TKIs in order to facilitate therapeutic drug monitoring (TDM) in clinical settings. This study sought to develop a simple and sensitive com-petitive enzyme-linked immunosorbent assay (ELISA) to quantify afatinib in plasma for routine phar-macokinetic applications. An anti-afatinib antibody was obtained using (S)-N-4-(3-chloro-4-fluor-ophenyl)-7-(tetrahydrofuran-3-yloxy)-quinazoline-4,6-diamine (CTQD), which has the same sub-structure as afatinib, as a hapten. Enzyme labeling of afatinib with horseradish peroxidase was similarly performed using CTQD. A simple competitive ELISA for afatinib was developed based on the principle of direct competition between afatinib and the enzyme marker for the anti-afatinib antibody, which had been immobilized on the plastic surface of a microtiter plate. Plasma afatinib concentrations below the limit of quantification of 30 pg/mL were reproducibly measurable. Also, the values of plasma afatinib levels measured from 20 patients were comparable with those measured by high-performance liquid chromatography, and there was a strong correlation between the values determined by both methods (Y = 0.976X – 0.207, r = 0.975). As indicated by its specificity and sensitivity, this newly developed ELISA for afatinib is an important tool for TDM and studies of the pharmacokinetics of afatinib.

BACKGROUND/AIMS: Few reports have described the long-term treatment outcomes of the anti-tumor necrosis factor-α antibody for Japanese Crohn’s disease (CD) patients. The aim of this study was to evaluate them and clarify the clinical factors that affect the long-term prognosis of the anti-tumor necrosis factor-α treatments. METHODS: This was a retrospective, observational, single-center cohort study. Japanese CD patients treated with either infliximab or adalimumab as a first-line therapy were analyzed. The cumulative retention rates of the biologics, relapse-free survival, and surgery-free survival were analyzed using Kaplan-Meier methods. The clinical factors associated with the long-term outcomes were estimated by both the log-rank test and Cox proportional hazard model. RESULTS: The cumulative retention rate was significantly higher in the group with a concomitant elemental diet of ≥900 kcal/day, baseline C-reactive protein (CRP) levels < 2.6 mg/dL, and baseline serum albumin levels ≥3.5 g/dL, respectively. The baseline serum albumin levels were also associated with both relapse-free and surgery-free survival. The lack of concomitant use of an elemental diet ≥900 kcal/day was identified as the only independent risk factor for the withdrawal of the biologics. CONCLUSIONS: Baseline CRP levels and serum albumin levels could affect the long-term outcomes in CD patients. Concomitant elemental diet of ≥900 kcal/day could have a positive influence on clinical treatment course.
Adalimumab ; Antibodies ; Asian Continental Ancestry Group ; Biological Products ; C-Reactive Protein ; Cohort Studies ; Crohn Disease ; Food, Formulated ; Humans ; Infliximab ; Necrosis ; Prognosis ; Proportional Hazards Models ; Retrospective Studies ; Risk Factors ; Serum Albumin

We herein report an extremely rare cardiac tumor of lymphatic malformation in 77-year-old man. The computed tomography (CT) demonstrated a mass from the lateral side of the left atrium to the lateral and posterior wall of the left ventricle among intrapericardial adipose tissue involving the left coronary artery. We performed partial resection of the tumor for definitive diagnosis under cardiopulmonary bypass. The histological finding was cardiac lymphatic malformation and was considered to be benign. There was no evidence of the growth of any cardiac tumor during the one-year follow up.