Facultad de Ciencias de la Salud

Discovery and clinical development of monoclonal antibodies with the ability to interfere in the regulation of the immune response have significantly changed the landscape of oncology in recent years. Among the active agents licensed by the regulatory agencies, nivolumab and pembrolizumab are paradigmatic as the most relevant ones according to the magnitude of available data derived from the extensive preclinical and clinical experience. Although in both cases the respective data sheets indicate well-defined dosage regimens, a review of the literature permits to verify the existence of many issues still unresolved about dosing the two agents, so it must be considered an open question of potentially important consequences, in which to work to improve the effectiveness and efficiency of use.

Objective: A review of the literature about the anti-programmed death 1 monoclonal antibody nivolumab permits to verify the existence of several issues still unresolved about their dosing schedule. The aim of the present work was to explore possibilities of nivolumab treatment personalization through therapeutic drug monitoring, in order to improve their effectiveness and efficiency. Method: Observational, prospective study carried out from May 2017 through June 2019 in patients with different tumor diagnoses treated with nivolumab. Blood samples were obtained in the routine clinical practice, once nivolumab steady state was reached. Serum nivolumab levels were determined by means of quantitative ELISA. The standard schedule of 3 mg/kg every two weeks (Q2W) was modified in some patients due to different circumstances, and resulting serum concentrations were compared with those from the non-modified patients and the published data. Results: Blood samples from 19 patients in treatment with nivolumab were analyzed. A total of 39 samples of nivolumab were analyzed between 6th and 27th cycles. The standard schedule of 3 mg/kg every two weeks was modified in 12/19 (60%) patients, with intervals of 3, 4, 5, 6 or 7 weeks, once the steady state was reached. No statistically significant differences were detected when comparing every two weeks and every four week intervals. When the intervals were six or seven weeks, mean plasma concentration showed a statistically significant difference compared with every two weeks. Conclusions: Current data contribute to confirm former suspects about the possibilities of exploring new scenarios to improve and personalize nivolumab dosage. Additional studies to confirm it in bigger series and correlate it with clinical results, and to better define the role of therapeutic drug monitoring in the treatment, are warranted, not only by financial concerns but also for improving quality of life of patients and clinical management aspects. / Objetivo: Una revisión de la literatura sobre nivolumab permite verificar la existencia de diversos aspectos sin resolver sobre su intervalo de dosificación. El objetivo del presente estudio ha sido explorar las posibilidades de personalización del tratamiento con nivolumab mediante la monitorización terapéutica de sus concentraciones séricas para mejorar su efectividad y eficiencia. Método: Estudio observacional, prospectivo, realizado entre mayo de 2017 y junio de 2019 en pacientes tratados con nivolumab que estaban diagnosticados de diferentes tumores. Se obtuvieron muestras de sangre en la práctica clínica habitual, una vez alcanzado el estado de equilibrio de nivolumab. Las concentraciones séricas de nivolumab fueron determinadas mediante ELISA cuantitativo. La pauta posológica habitual de 3 mg/kg cada dos semanas tuvo que ser modificada en algunos pacientes debido a diferentes circunstancias, y las concentraciones séricas resultantes se compararon con las correspondientes a los pacientes en los que no se modificó y con datos publicados. Resultados: Se analizaron muestras de 19 pacientes que recibieron inicialmente 3 mg/kg de nivolumab cada dos semanas. Se analizó un total de 39 muestras, entre los ciclos 6 y 27. La pauta habitual se modificó, una vez alcanzado el estado de equilibrio, en 12/19 (60%) pacientes, en los que se amplió el intervalo a 3, 4, 5, 6 o 7 semanas. No se encontraron diferencias estadísticamente significativas al comparar la maadministración cada dos semanas y cada cuatro semanas. Cuando los intervalos fueron de seis o siete semanas, la concentración sérica media mostró una diferencia estadísticamente significativa en comparación con la administración cada dos semanas. Conclusiones: La información recogida parece confirmar la necesidad de explorar nuevos escenarios para personalizar la dosificación de nivolumab. Se necesitan estudios adicionales en series de mayor tamaño para confirmar esta información, correlacionarla con los resultados clínicos y definir mejor el papel de la monitorización terapéutica, no solo por motivos económicos, sino también para mejorar la calidad de vida de los pacientes y facilitar la administración clínica del tratamiento.