Dried Blood Spot (DBS) as a useful tool to improve clozapine, aripiprazole and paliperidone treatment: From adherence to efficiency.

INTRODUCTION: Therapeutic Drug Monitoring (TDM) of antipsychotics in schizophrenia is a powerful tool that allows tailoring the treatment in an individualized approach. Our goals are to develop and validate a Dried Blood Spot (DBS) method for monitoring some commonly used antipsychotics (aripiprazole, clozapine, and paliperidone) and to evaluate its usefulness as a compliance biomarker, as well as in drug-dose adjustment to personalize the antipsychotic treatment to improve its efficacy and safety. METHODS: 31 first-psychotic episode (FEP) and schizophrenia patients were included; 5 refer to naïve FEP who started antipsychotic treatment; 26, to patients with more than one episode and under antipsychotic treatment: aripiprazole (7 cases), clozapine (17), paliperidone (11). For DBS sample collection, 25µl of capillary blood were placed in the spot of a FTA™DMPK-C-card. After completely dryness, antipsychotics were extracted and analyzed by a validated UHPLC-MS/MS-method. DBS antipsychotic results were compared with those obtained in venous blood/plasma. RESULTS: Aripiprazole, paliperidone and clozapine showed from good to excellent correlations between concentrations in venous blood and DBS capillary blood (r2, from 0.500 to 0.721). The correlation between conventional plasma and DBS concentrations for paliperidone, aripiprazole, clozapine, and their metabolites were moderate, suggesting that optimal drug target concentrations should be established for DBS. CONCLUSIONS: In this study, for aripiprazole, dehydroaripiprazole, paliperidone, clozapine and desmethylclozapine, DBS has provided good analytical performance for TDM. Thus, DBS sampling can offer a great alternative over conventional sampling for plasma measurement. The assay provides good analytical performances for TDM and clinical research applicability, suggesting that DBS is a promising clinical application in TDM in psychiatry.

Dried Blood Spot (DBS) as a useful tool to improve clozapine, aripiprazole and paliperidone treatment: From adherence to efficiency / Análisis de sangre seca (Dried Blood Spot [DBS]) como herramienta útil para mejorar el tratamiento con clozapina, aripiprazol y paliperidona: de la adherencia a la eficacia

Introduction: Therapeutic Drug Monitoring (TDM) of antipsychotics in schizophrenia is a powerful tool that allows tailoring the treatment in an individualized approach. Our goals are to develop and validate a Dried Blood Spot (DBS) method for monitoring some commonly used antipsychotics (aripiprazole, clozapine, and paliperidone) and to evaluate its usefulness as a compliance biomarker, as well as in drug-dose adjustment to personalize the antipsychotic treatment to improve its efficacy and safety. Methods: 31 first-psychotic episode (FEP) and schizophrenia patients were included; 5 refer to naïve FEP who started antipsychotic treatment; 26, to patients with more than one episode and under antipsychotic treatment: aripiprazole (7 cases), clozapine (17), paliperidone (11). For DBS sample collection, 25μl of capillary blood were placed in the spot of a FTA™DMPK-C-card. After completely dryness, antipsychotics were extracted and analyzed by a validated UHPLC-MS/MS-method. DBS antipsychotic results were compared with those obtained in venous blood/plasma. Results: Aripiprazole, paliperidone and clozapine showed from good to excellent correlations between concentrations in venous blood and DBS capillary blood (r2, from 0.500 to 0.721). The correlation between conventional plasma and DBS concentrations for paliperidone, aripiprazole, clozapine, and their metabolites were moderate, suggesting that optimal drug target concentrations should be established for DBS. (AU)

Introducción: La monitorización terapéutica de medicamentos (Therapeutic Drug Monitoring [TDM]) de los antipsicóticos en la esquizofrenia es una potente herramienta que permite adaptar el tratamiento de forma individualizada y personalizada. Los objetivos del presente estudio son desarrollar y validar un método de análisis en sangre seca (Dried Blood Spot [DBS]) para la monitorización de algunos antipsicóticos de uso común (aripiprazol, clozapina y paliperidona) y evaluar su utilidad como biomarcador de cumplimiento y adherencia terapéutica, así como en el ajuste de la dosis del fármaco para personalizar el tratamiento antipsicótico para mejorar su eficacia y su seguridad. Metodología: Se incluyeron 31 pacientes con un primer episodio psicótico (PEP) o un diagnóstico de esquizofrenia; 5 eran PEP que iniciaron tratamiento antipsicótico, y 26 eran pacientes con más de un episodio y que seguían tratamiento con antipsicóticos: aripiprazol (7 casos), clozapina (17), paliperidona (11). Para la recogida de muestras de DBS se colocaron 25μl de sangre capilar en el punto de una tarjeta FTATMDMPK-C. Tras secarse completamente, se extrajeron los antipsicóticos y se analizaron mediante un método UHPLC-MS/MS validado. Los resultados de los antipsicóticos según la DBS se compararon con los obtenidos en sangre venosa/plasma. Resultados: El aripiprazol, la paliperidona y la clozapina mostraron de buenas a excelentes correlaciones entre las concentraciones en sangre venosa y en sangre capilar del DBS (r2, de 0,500 a 0,721). La correlación entre las concentraciones plasmáticas convencionales y las del DBS para la paliperidona, el aripiprazol, la clozapina y sus metabolitos fue moderada, lo que sugiere que se deberían definir y establecer concentraciones óptimas del fármaco para el DBS. (AU)

Monitoring of miR-181a-5p and miR-155-5p Plasmatic Expression as Prognostic Biomarkers for Acute and Subclinical Rejection in de novo Adult Liver Transplant Recipients.

Background and Aims: News strategies for the accurate assessment of the state of immunosuppression (IS) in liver transplant recipients are needed to prevent rejection and minimize drug-related side effects. miRNAs can potentially be used as diagnostic or prognostic biomarkers in transplant patients. This study evaluated the capacity of a plasmatic miRNA panel (miR-155-5p, miR-122-5p, miR-181a-5p, and miR148-3p) as an early non-invasive prognostic and diagnostic biomarker for T cell-mediated acute rejection (TCMAR) and subclinical rejection (SCR) in adult liver recipients. Methods: A total of 145 liver recipients were included. All patients received a calcineurin inhibitor with or without mycophenolate mofetil and methylprednisolone. Plasmatic miRNA expression was assessed by qPCR before and at different time-points after liver transplantation. Results: Seventeen patients experienced TCMAR, and eight were diagnosed with SCR during the protocol biopsy at the 3rd month post-transplantation. Pre-transplantation, miR-155-5p expression was significantly higher in TCMAR patients and in SCR patients than in non-rejectors, and miR-181a-5p expression was also significantly higher in SCR patients than in non-rejectors. Post-transplantation, before transaminase-level modification, significantly increased miR-181a-5p, miR-155-5p, and miR-122-5p expression was observed in TCMAR and SCR patients. Binary logistic regression analyses showed, post-transplantation, that TCMAR risk was better predicted by individual expression of miR-181a-5p (LOGIT = -6.35 + 3.87*miR-181a-5p), and SCR risk was better predicted by the combination of miR-181a-5p and miR-155-5p expression (LOGIT = -5.18 + 2.27*miR-181a-5p+1.74*miR-155-5p). Conclusions: Pre-transplantation plasmatic miR-155-5p expression may be useful for stratifying low-immunologic-risk patients, and post-transplantation miR-181a-5p and miR-155-5p may be candidates for inclusion in early, non-invasive prognostic biomarker panels to prevent TCMAR or SCR and better identify patient candidates for IS minimization. Large prospective randomized multicenter trials are needed to refine the cut-off values and algorithms and validate the clinical usefulness of these biomarkers.