分类: 医学、药学 >> 临床医学 提交时间: 2022-12-22
目的与背景癫痫(Epilepsia)作为一种常见的神经系统疾病。药物治疗是目前主要的治疗手段。丙戊酸(Valproic acid, VPA)是临床常用的一线抗癫痫药物(Antiepileptic drugs, AEDs)。由于该药个体间变异大,治疗窗窄,目前推荐对VPA进行治疗药物监测(Therapeutic drug monitoring, TDM)和个体化药物治疗。由于癫痫需要长期治疗,药物依从性是临床关注的重要问题。漏晚或服药物事件发生时,一个合理的补救给药方案,对于控制癫痫发作,避免严重不良药物反应,具有重要的临床意义。而目前缺乏相关的研究报道。本研究以VPA为研究药物,旨在:1.检索查阅VPA药代动力学文献,收集不同地区使用VPA癫痫患者的群体药动学特征;2.建立典型病例与用药依从性不佳及用药补救场景,以收集的VPA群体药动学群体参数为基础,采用蒙特卡洛模拟评估依从性不佳对VPA药动学过程的影响以及制定相应的补救给药方案。方法本研究通过检索数据库,对VPA药代动力学评价分析,并收集并建立了群体药动学人群特征的文献。先使用文献管理软件进行初筛,再按照一定的入排标准纳入合适的文献。收集文献中的病人数,建模浓度点数,男女比例,年龄,体重,采样时间点,药物剂型等建模信息,以及群体药动学固定效应参数和随机效应参数等描述人群特征信息。使用NONMEM(Nonlinear mixed effect modeling)程序进行人群特征的还原。以纳入的癫痫患者VPA群体药动学特征为基础,以蒙特卡洛模拟产生漏延迟服药场景下的VPA血药浓度随时间变化的数据。定义1000例典型病例的P5-P95浓度波动范围为该典型病例的个体治疗范围。使用个体治疗范围评估不同依从性场景下对VPA药动学过程的影响,并以此设计相应的药物补救方案。此外,对以上场景进行敏感性分析,进一步考察吸收速率Ka、合并其抗癫痫药物(卡马西平,苯妥英,左乙拉西坦等)、服药时间(计划服药前后30min)以及不同的给药间隔对补救给药方案的影响。结果最终共纳入11篇VPA既往群体药动学研究,并收集群体药动学特征。模拟结果显示,延迟服药事件发生时,VPA浓度低于治疗范围的风险随着延迟服药时间的延长呈升高趋势,并且具有剂量依赖性,剂量越大风险越高;最佳补救给药剂量与给药方案和延迟服药时间有关,不同的给药方案的补救剂量有所不同。敏感性分析显示Ka、合并用药以及在计划给药时间前后30min服药对补救给药方案无显著影响。结论基于以上分析,本研究最终制定了癫痫患者VPA120-240mg q12h和缓释片500mg,750mg q12h以及500mg,750mg,1000mg q24h治疗方案下的延迟服药或漏服药的补救给药方案方案。蒙特卡罗法为制定依从性不佳时的补救剂量推荐方案提供了强有力的工具。本研究基于上述原理,首次计算了针对VPA患者依从性不佳时的补救剂量推荐方案,供临床参考。
分类: 医学、药学 >> 临床医学 提交时间: 2020-09-07
摘要: Objective: Delayed or missed doses are unavoidable in the pharmacotherapy of epilepsy and significantly compromise the efficacy of antiepileptic drug treatment. An inappropriate remedial regimen can cause seizure relapse or serious adverse events. This study investigated the effect of delayed or missed doses on the pharmacokinetics (PK) of valproic acid (VPA) in patients with epilepsy and established remedial dosing recommendations for nonadherent patients. Methods: Monte Carlo simulations are based on all previous population pharmacokinetic models for pediatric, adult and elderly patients with epilepsy. The following four remedial strategies were investigated for each delayed dose: A) A partial dose or a regular dose is taken immediately; a regular dose is taken at the next scheduled time. B) The delayed dose was administered immediately, followed by a partial dose at the next scheduled time. C) The delayed dose and a partial dose are taken; the next scheduled time is skipped, and the regular regimen is resumed. D) Double doses are taken when missed one dose or two doses, and the regular regimen at the subsequent scheduled time is resumed. Results: The recommended remedial dose was related to the delay duration and daily dose. Remedial dosing strategies A and B were almost equivalent, whereas Strategy C was recommended when the delayed dose was close to the next scheduled dose. Strategy D was only suggested for delayed two doses. Conclusion: Simulations provide quantitative insight into the remedial regimens for nonadherent patients, and clinicians should select the optimal regimen for each patient based on the individual's status.