Eficiencia de los agentes biológicos en el tratamiento de la psoriasis moderada-grave / Efficiency of Biologic Agents in the Treatment of Moderate to Severe Psoriasis

Introducción. Los agentes biológicos en el tratamiento de la psoriasis son más caros y, en general, de eficacia similar o superior que la terapia clásica. Sin embargo, se desconoce su eficiencia en términos de coste/eficacia (coste por cada paciente que responde en las condiciones de los ensayos clínicos). Objetivo. Estimar los cocientes de coste/eficacia de adalimumab, etanercept, infliximab y efalizumab en el manejo de la psoriasis moderada-grave. Material y métodos. Modelo de evaluación económica, construyendo un árbol de decisión para cada uno de los tratamientos sobre los que existe evidencia científica. Se ha usado la perspectiva del financiador (Sistema Nacional de Salud), considerando sólo los costes del fármaco. La eficacia (proporción de pacientes que responden con el criterio PASI-75) asignada es la que consta en los ensayos clínicos. Cuando había más de un ensayo para cada tratamiento se han realizado metanálisis. Cuando la dosis depende del peso, este último en los sujetos del estudio se ha estandarizado por edad y sexo a la población española, corregido por el incremento de peso de los sujetos con psoriasis. La incertidumbre se ha manejado mediante análisis de sensibilidad. Resultados y conclusiones. Asignando en los modelos la eficacia de los 15 ensayos clínicos publicados, el agente biológico más eficiente en términos de coste/eficacia es adalimumab, con el que se consigue un respondedor PASI-75 a un coste de 8.013 euros. Con el resto de los biológicos y con diferentes pautas el coste/respondedor osciló entre 9.370 € y 17.112 €. El análisis de sensibilidad confirma la robustez de estos hallazgos (AU)

Background. In the treatment of psoriasis, biologic agents are more expensive than conventional therapy while showing similar or superior efficacy. However, their efficiency in terms of cost/efficacy (cost per responder in clinical trial conditions) is unknown. Objective. To estimate the cost/efficacy ratios of adalimumab, etanercept, infliximab, and efalizumab in the management of moderate to severe psoriasis. Material and Methods. A model for the costs analysis was elaborated by building a decision tree for each of the treatments for which scientific evidence was available. The payer perspective (Spanish national health system) was used, only considering drug costs. The efficacy (proportion of patients who respond according to Psoriasis Area Severity Index [PASI] 75 criterion) was assigned according to the results of the clinical trials. When more than1 trial was available per treatment, a meta-analysis was undertaken. In the case of weight-dependent dosing, the weight of the study participants was adjusted by age and sex to the standard Spanish population with correction for increased weight in individuals with psoriasis. Uncertainty was investigated with a sensitivity analysis. Results and Conclusions. Assigning the efficacy reported in the 15 published clinical trials, the most efficient biologic agent in terms of the cost/efficacy ratio was adalimumab, with one PASI 75 response at a cost of €8,013. For the remaining biologic agents and with different regimens, the cost per responder ranged from €9,370 to €17,112. The sensitivity analysis confirmed the robustness of these figures (AU)

Effect of the mode of calcitriol administration on PTH-ionized calcium relationship in uraemic patients with secondary hyperparathyroidism.

To assess the effect of the different modes of calcitriol administration on PTH-ionized calcium relationship we conducted a prospective clinical trial in 33 patients on chronic haemodialysis with secondary hyperparathyroidism (four times upper normal limit intact PTH) who were randomly assigned, with stratification to PTH levels, to receive daily oral, intermittent oral, or intermittent intravenous calcitriol at the same dose of 0.045 micrograms/kg/weekly. PTH-iCa curves were generated by inducing hypo- or hypercalcaemia in sequential haemodialysis 1 week apart, before and after 10 weeks on treatment. All patients were dialysed against a dialysate calcium concentration of 2.5 mEq/l throughout the study period. After drop-outs, 26 patients completed the study: 11 on intravenous calcitriol (mean basal PTH +/- SD: 666 +/- 280 pg/ml), eight on intermittent oral calcitriol (mean basal PTH: 831 +/- 361), and seven on daily oral calcitriol (mean basal PTH: 719 +/- 280). Serum ionized calcium and phosphorus significantly increased in intravenous and daily oral groups after calcitriol treatment, but not in the intermittent oral group. Basal PTH did not significantly change in the three groups after 10 weeks on treatment. Maximal PTH significantly decreased in intravenous group (1449 +/- 660 versus 1122 +/- 691 pg/ml, P = 0.0085) and at the limit of statistical significance in the intermittent oral group (1701 +/- 774 versus 1445 +/- 634, P = 0.12), but it did not change in the daily oral group. Minimal PTH did not modify in the three groups. In all three groups, a shift to the right in the PTH-iCa relationships were observed, with significant changes in the set point of calcium.(ABSTRACT TRUNCATED AT 250 WORDS)