Abstract

In this paper, we explore dynamic market share and public healthcare costs of trastuzumab’s evergreening (subcutaneous) variant during introduction of trastuzumab’s competitive biosimilar variants in the Netherlands. We used a time series design to assess dynamic market share of trastuzumab’s evergreening variant after introducing trastuzumab’s biosimilar variants, focusing on the number of treatments and patients. The public healthcare costs of this evergreening strategy were estimated using administrative claims data. Our results show that the original trastuzumab was completely replaced by the subcutaneous and biosimilar variants. The uptake of the subcutaneous form peaked at 50% market share but after the introduction of biosimilars progressively reduced to a market share of 20%, resulting in a more competitive market structure. The public healthcare costs for trastuzumab significantly decreased after the introduction of the biosimilars. After the introduction of the biosimilars, a substantial price drop is visible, with the subcutaneous version, still under patent, also falling sharply in price but less strongly than the iv/biosimilar version. As the costs are publicly funded, we recommend a more explicit societal debate to consider if the potential benefits of subcutaneous Herceptin^® (and other similar medicines) are worth the additional costs, and at which price it should be reimbursed as the part of the benefit package.

中文翻译：

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接近专利到期的“常青”战略对生物仿制药的采用和公共医疗保健成本的影响：荷兰引入曲妥珠单抗第二种给药形式的案例研究

摘要

在本文中，我们探讨了在荷兰引入曲妥珠单抗竞争性生物仿制药变体期间曲妥珠单抗常青（皮下）变体的动态市场份额和公共医疗成本。在引入曲妥珠单抗的生物仿制药变体后，我们使用时间序列设计来评估曲妥珠单抗常青变体的动态市场份额，重点关注治疗数量和患者数量。这一常青战略的公共医疗保健成本是使用行政索赔数据估算的。我们的结果表明，原始曲妥珠单抗完全被皮下注射和生物仿制药变体所取代。皮下注射剂型的市场份额最高为 50%，但在引入生物仿制药后，市场份额逐渐降至 20%，从而形成了更具竞争力的市场结构。推出生物仿制药后，曲妥珠单抗的公共医疗费用显着下降。生物仿制药推出后，价格大幅下降，仍处于专利保护状态的皮下注射版本价格也大幅下降，但不如静脉注射/生物仿制药版本。由于费用由公共资助，我们建议进行更明确的社会辩论，以考虑皮下注射赫赛汀^®（和其他类似药物）的潜在益处是否值得额外费用，以及应以什么价格作为收益的一部分进行报销包裹。