罗氏新药Kadcyla有望弥补赫赛汀专利悬崖
         2013年8月3日讯 /生物谷BIOON/ --根据独立分析公司Datamonitor Healthcare发布的报告，瑞士制药巨头罗氏（Roche）突破性的HER2阳性乳腺癌药物赫赛汀（Herceptin，通用名：曲妥珠单抗，trastuzumab）的生物仿制药预计将于2016年上市。
 
但分析师称，罗氏抗体偶联药物（ADC）新药——Kadcyla（ado-trastuzumab emtansine）销售增长的日益成功，将有助于缓解销售收入的下降，同时让罗氏继续保持其在HER2阳性乳腺癌市场中的霸主地位。
 
罗氏的赫赛汀（Herceptin）于1998年上市，被视为HER2阳性乳腺癌治疗的一个重大突破。自上市以来，便统治了HER2阳性乳腺癌市场，同时也成为了罗氏的重磅药物，该药2013年上半年的销售额达到了33.1亿美元。
 
赫赛汀（Herceptin）专利悬崖
 
Herceptin在欧洲和日本的专利将于2014年到期，在美国的专利将于2015年到期。目前，数个Herceptin生物仿制药已进入III期临床开发，预计将于2016年进入市场。这些Herceptin生物仿制药的售价，预计将大幅低于罗氏的品牌药，同时将在成本保守市场（cost-conservative markets）与品牌药展开激烈竞争，如英国市场。
 
Datamonitor分析师Aine Slowey称，罗氏希望其抗体偶联药物Kadcyla的销售增长能够弥补Herceptin专利到期所致的销售收入下降。早期的迹象非常积极，Kadcyla在2013年第一季度在美国的销售额便达到了8700万美元，尽管该药才于今年2月获得FDA的批准。
 
患者已开始接受Kadcyla
 
Datamonitor Healthcare对美国临床医师的一项调查显示，Kadcyla获批不到4周时，9%的IV期HER2阳性乳腺癌患者已在二线治疗中采用Kadcyla，8%的患者已在三线治疗中采用Kadcyla。这种快速接纳，使得Kadcyla能够在上市之后的很短时间内便产生了显著的销售收入。
 
同时，Kadcyla在HER2阳性乳腺癌患者中的耐受性良好，仅有10%的患者需要降低Kadcyla的剂量，这些患者接受推荐剂量的89%。（生物谷Bioon.com）
 
英文原文：Roche hopes Kadcyla will replace revenue lost by Herceptin patent expiry
 
Article | 02 August 2013 Swiss drug major Roche (ROG: SIX) could be hit by biosimilar versions of its breakthrough HER2-positive breast cancer drug Herceptin  (trastuzumab)  which are expected to come to market in 2016, according to independent analysis firm Datamonitor Healthcare.
 
But the analysts say that Roche will hope that the growing success of its antibody-drug conjugate, Kadcyla (ado-trastuzumab emtansine), will help the company mitigate this drop in revenue, and allow Roche to maintain its dominance of the HER2-positive breast cancer market.
 
The launch of Roche’s Herceptin in 1998 was deemed to be a major breakthrough for patients with HER2-positive breast cancer, who until this time had few alternative treatment options to combat the aggressive disease. Since its launch, Herceptin has gained massive uptake in the HER2-positive breast cancer market, with 85% of Stage IV patients in the first-line setting receiving a treatment regimen incorporating Herceptin. It has also become a blockbuster earner for Roche, generating first-half 2013 sales of 3.08 billion Swiss francs ($3.31 billion; The Pharma Letter July 25).
 
Patent cliff ahead
 
Patents for Herceptin are due to expire in 2014 in Europe and Japan, and in 2015 in the USA. Biosimilar versions of Herceptin are already in Phase III development, and are expected to come to market from 2016. These Herceptin biosimilars are expected to be priced significantly lower than the current cost of branded Herceptin, and will strongly compete with the branded therapy in cost-conservative markets such as the UK.
 
áine Slowey, an analyst at Datamonitor, said: “Roche will be hoping that the uptake of its antibody-drug conjugate, Kadcyla, will compensate for the decline in sales revenue associated with Herceptin’s patent expiry. The early signs are very positive. Kadcyla has generated US sales of $87 million in the first half of this year, despite only gaining approval in February.”
 
Patients already receiving Kadcyla
 
A Datamonitor Healthcare survey of US physicians less than four weeks after Kadcyla’s approval indicated that 9% of US Stage IV HER2-positive breast cancer patients were already receiving the drug in the second-line setting. Similar uptake was observed in the third-line setting, with 8% of patients already receiving Kadcyla. This rapid uptake has allowed Kadcyla to generate significant commercial revenue in the short time it has been on the market.
 
Kadcyla also appears to be well tolerated by patients in this treatment setting. Only 10% of those receiving Kadcyla require dose reduction, with these patients receiving 89% of the recommended dose.