Valganciclovir (VGCV) and ganciclovir (GCV) doses must be adjusted according to indication, renal function and weight. No specific therapeutic exposure values have been established. We aimed to evaluate the adequacy of VGCV/GCV doses, to assess the interpatient variability in GCV serum levels, to identify predictive factors for this variability and to assess the clinical impact. This is a prospective study at a tertiary institution including hospitalized patients receiving VGCV/GCV prophylaxis or treatment. Adequacy of the antiviral dose was defined according to cytomegalovirus guidelines. Serum levels were determined using High-Performance Liquid Chromatography. Blood samples were drawn at least 3 days after antiviral initiation. Outcome was considered favorable if there was no evidence of cytomegalovirus infection during prophylaxis or when a clinical and microbiological resolution was attained within 21 days of treatment and no need for drug discontinuation due to toxicity. Seventy consecutive patients [74.3% male/median age: 59.2 years] were included. VGCV was used in 25 patients (35.7%) and GCV in 45 (64.3%). VGCV/GCV initial dosage was deemed adequate in 47/70 cases (67.1%), lower than recommended in 7/70 (10%) and higher in 16/70 (22.9%). Large inter-individual variability of serum levels was observed, with median trough levels of 2.3 mg/L and median peak levels of 7.8 mg/L. Inadequate dosing of VGCV/GCV and peak levels lower than 8.37 or greater than 11.86 mg/L were related to poor outcome. Further studies must be performed to confirm these results and to conclusively establish if VGCV/GCV therapeutic drug monitoring could be useful to improve outcomes in specific clinical situations.

中文翻译：

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缬更昔洛韦—更昔洛韦的使用和系统治疗药物监测。抗病毒管理的邀请

必须根据适应症，肾功能和体重调整缬更昔洛韦（VGCV）和更昔洛韦（GCV）的剂量。没有确定具体的治疗暴露值。我们旨在评估VGCV / GCV剂量的适当性，评估患者之间GCV血清水平的变异性，确定该变异性的预测因素并评估临床影响。这是在第三级机构中进行的前瞻性研究，其中包括接受VGCV / GCV预防或治疗的住院患者。根据巨细胞病毒指南确定抗病毒剂量的适当性。使用高效液相色谱法测定血清水平。抗病毒起始后至少3天抽取血样。如果在预防期间没有证据表明巨细胞病毒感染，或者在治疗后21天内达到临床和微生物学解决方案，并且由于毒性而无需停药，则结果被认为是有利的。包括七十名连续的患者[男性/中位数年龄为74.3％：59.2岁]。VGCV用于25例患者（35.7％），GCV用于45例（64.3％）。VGCV / GCV初始剂量在47/70例中被认为是适当的（67.1％），低于建议的7/70（10％）和更高的16/70（22.9％）。观察到血清水平之间存在较大的个体差异，中值谷值水平为2.3 mg / L，中值峰水平为7.8 mg / L。VGCV / GCV的剂量不足和峰值水平低于8.37或高于11.86 mg / L与不良预后有关。