Caram Megan E V, Borza Tudor, Min Hye-Sung, Griggs Jennifer J, Miller David C, Hollenbeck Brent K, Mukherjee Bhramar, Skolarus Ted A
University of Michigan and VA Ann Arbor Healthcare System, Ann Arbor, MI.
J Oncol Pract. 2017 Aug;13(8):e694-e702. doi: 10.1200/JOP.2016.020206. Epub 2017 Jun 19.
Abiraterone and enzalutamide were approved by the Food and Drug Administration in 2011 and 2012 to treat men with metastatic castration-resistant prostate cancer (mCRPC). Most men with mCRPC are > 65 years of age and thus eligible for Medicare Part D. We conducted a study to better understand the early dissemination of these drugs across the United States using national Medicare Part D data.
We evaluated the number of prescriptions for abiraterone and enzalutamide by provider specialty and hospital referral region (HRR) using Medicare Part D and Dartmouth Atlas data. We categorized HRRs by abiraterone and enzalutamide prescriptions, adjusted for prostate cancer incidence, and examined factors associated with regional variation using multilevel regression models.
Among providers who wrote the majority of prescriptions for abiraterone or enzalutamide in 2013 (n = 2,121), 87.5% were medical oncologists, 3.3% were urologists, and 9.2% were other provider specialties. Among prescribers, approximately 30% were responsible for three quarters of the claims for abiraterone and 20% were responsible for more than half the claims for enzalutamide. Some HRRs demonstrated low-prescribing rates despite average medical oncology and urology physician workforce density. Our multilevel model demonstrated that regional factors potentially influenced variation in care.
The majority of prescriptions written for abiraterone and enzalutamide through Medicare Part D in 2013 were written by a minority of providers, with marked regional variation across the United States. Better understanding of the early national dissemination of these effective but expensive drugs can help inform strategies to optimize introduction of new, evidence-based mCRPC treatments.
阿比特龙和恩杂鲁胺分别于2011年和2012年获美国食品药品监督管理局批准，用于治疗转移性去势抵抗性前列腺癌（mCRPC）男性患者。大多数mCRPC男性患者年龄超过65岁，因此符合医疗保险D部分的资格。我们开展了一项研究，利用全国医疗保险D部分的数据，以更好地了解这些药物在美国的早期推广情况。
我们使用医疗保险D部分和达特茅斯地图集数据，按医疗服务提供者专业和医院转诊区域（HRR）评估阿比特龙和恩杂鲁胺的处方数量。我们根据阿比特龙和恩杂鲁胺的处方对HRR进行分类，并针对前列腺癌发病率进行调整，然后使用多水平回归模型检查与区域差异相关的因素。
在2013年开具阿比特龙或恩杂鲁胺大多数处方的医疗服务提供者中（n = 2121），87.5%为医学肿瘤学家，3.3%为泌尿科医生，9.2%为其他专业的医疗服务提供者。在开处方者中，约30%负责四分之三的阿比特龙报销申请，20%负责超过一半的恩杂鲁胺报销申请。尽管医学肿瘤学和泌尿科医生劳动力密度平均，但一些HRR的处方率较低。我们的多水平模型表明，区域因素可能影响了医疗差异。
2013年通过医疗保险D部分开具的阿比特龙和恩杂鲁胺处方，大多数是由少数医疗服务提供者开具的，美国各地存在明显的区域差异。更好地了解这些有效但昂贵药物在全国的早期推广情况，有助于为优化引入新的、基于证据的mCRPC治疗策略提供信息。
