Department of Pharmacy, The Comparative Health Outcomes, Policy & Economics (CHOICE) Institute, University of Washington, Seattle, WA, USA.
Pharmacoepidemiol Drug Saf. 2020 Jun;29(6):675-683. doi: 10.1002/pds.5021. Epub 2020 May 4.
Studies of medication persistence in plaque psoriasis have shown inconsistent results, likely due to differing definitions of nonpersistence and of the permissible gap between refills. Also, medication persistence information for two recently approved drugs, apremilast and ixekizumab, is limited.
We use the Truven Health MarketScan claims database to assess persistence for six drugs: adalimumab, apremilast, etanercept, ixekizumab, secukinumab, and ustekinumab. We define the permissible gap in three ways: 150 days for ustekinumab and 90 days for all other drugs (150/90 model); 120 days for all drugs (120 model); and twice the days' supply for all drugs (days' supply model). To estimate unadjusted persistence, we use Kaplan-Meier curves, and a proportional hazards model to estimate the adjusted risk of non-persistence.
Ustekinumab is most sensitive to changes in the definition of permissible gap, likely because of its longer maintenance dosing interval. Among targeted drug-experienced patients using ustekinumab, median persistence is 358 days (95% confidence interval: 343-371) in the 150/90 model and 189 days (179-199) in the days' supply model. Among targeted drug-experienced patients, median persistence in the days' supply model is longest for ixekizumab and secukinumab at 252 (217-301) and 222 (210-244) days, respectively. We also find that adjusted risk of nonpersistence increases by approximately 1% per year at treatment start.
The definition of permissible gap meaningfully changes both absolute and ordinal estimates of medication persistence. Each definition has unique limitations, which should be considered when interpreting persistence data.
斑块状银屑病药物维持治疗的研究结果不一致，这可能是由于药物维持治疗的定义和允许的药物补充间隔不同。此外，最近批准的两种药物阿普米司特和依奇珠单抗的药物维持治疗信息有限。
我们使用 Truven Health MarketScan 理赔数据库评估六种药物的维持治疗情况：阿达木单抗、阿普米司特、依那西普、依奇珠单抗、司库奇尤单抗和乌司奴单抗。我们通过三种方式定义允许的药物补充间隔：乌司奴单抗为 150 天，其他所有药物为 90 天（150/90 模型）；所有药物为 120 天（120 模型）；所有药物为药物供应天数的两倍（供应天数模型）。为了估计未经调整的药物维持治疗，我们使用 Kaplan-Meier 曲线，并用比例风险模型估计药物不维持治疗的风险。
乌司奴单抗对允许的药物补充间隔定义的变化最为敏感，这可能是由于其维持治疗的间隔时间较长。在使用乌司奴单抗的靶向药物治疗经验患者中，150/90 模型的中位药物维持治疗时间为 358 天（95%置信区间：343-371），供应天数模型为 189 天（179-199）。在靶向药物治疗经验患者中，供应天数模型的中位药物维持治疗时间最长的是依奇珠单抗和司库奇尤单抗，分别为 252 天（217-301）和 222 天（210-244）。我们还发现，治疗开始时，药物不维持治疗的风险每年增加约 1%。
允许的药物补充间隔的定义显著改变了药物维持治疗的绝对和序贯估计值。每种定义都有其独特的局限性，在解释药物维持治疗数据时应考虑这些局限性。
