2014年12月21日讯 /生物谷BIOON/ --本月初，默沙东95亿美元大手笔收购抗生素巨头Cubist，该笔交易的关键产品Zerbaxa在圣诞节前夕拿到FDA批文，加上本月上旬超级HPV疫苗Gardasil 9获批上市，默沙东近来真是喜事不断，乐的都合不拢嘴了！业界预测，Zerbaxa将在2023年达到11.5亿美元的峰值。
抗生素巨头Cubist近日宣布，FDA已批准抗生素复方新品Zerbaxa（ceftolozane/他唑巴坦）用于成人患者治疗由易感革兰氏阴性菌导致的复杂性尿路感染（cUTI）和复杂性腹腔内感染（cIAI）。Zerbaxa的获批，也标志着Cubist在2014年拿下的第2个FDA批文。今年6月，FDA已批准Cubist新型抗生素Sivextro（tedizolid phosphate，第二代恶唑烷酮类抗生素），用于治疗由金黄色葡萄球菌、多种链球菌及粪肠球菌引发的急性细菌性皮肤及皮肤组织感染（ABSSSI）。
Zerbaxa也是默沙东大手笔95亿美金收购Cubist的关键因素。Zerbaxa的获批，对于Cubist而言也非常重要，该公司主打产品Cubicin（达托霉素）在2013年的全球销售额超过10亿美元，但本月上旬FDA联邦法院判决Cubicin四项专利无效，并裁决Hospira公司最快可在2016年推出Cubicin仿制药，比预期专利到期时间提前两年。在欧盟监管方面，Cubist预计Zerbaxa将在2015年下半年获批上市。
目前，面对日趋严峻的“抗菌”形势，一些国家已经开始采取激励措施，鼓励新抗生素的研发。美国于2012年7月通过了《鼓励开发抗生素法案》(GAIN)，根据规定，符合标准的抗生素药物将获得额外五年的市场独占权，以帮助开发者收回投资。
Zebraxa就是根据《鼓励开发抗生素法案》(GAIN)批准治疗革兰氏阴性菌的首个新抗生素产品。根据GAIN法案，FDA已授予Zerbaxa合格传染病产品（QIDP）资格。据估计，在美国每年由革兰氏阴性菌感染导致的病例高达200万例，死亡病例23000例，导致的直接医疗费用高达200亿美元。
Zerbaxa是FDA在2014年批准的第四款抗生素产品。今年5月、6月和8月，FDA分别批准了阿特维斯（Actavis）的Dalvance、Cubist的Sivextro、Medicines公司的Orbactiv（奥利万星）。
不过，Zerbaxa不久后也将面临其他对手的竞争，包括阿斯利康和阿特维斯，这2家的产品预计将在2015年第一季度获FDA批准上市；此外，Tetraphase公司也正在一款抗生素产品用于cUTI和cIAI的治疗。Zerbaxa的获批，是基于2项关键III期临床研究的积极数据。其中一项研究在复杂性尿路感染（cUTI）患者中开展，另一项在复杂性腹腔内感染（cIAI）患者中开展。这2项研究均达到了主要终点。
英文原文：FDA approves Cubists' drug for antibiotic-resistant bacteria
(Reuters) - Cubist Pharmaceutical Inc's drug to treat complicated urinary tract and intra-abdominal infections won U.S. approval on Friday, highlighting the regulator's interest in tackling the growing threat of the so-called superbugs.
Cubist shares were up 1.9 percent in extended trading.
The drug, Zerbaxa, treats infections caused by gram-negative bacteria — a type of antibiotic-resistant pathogens, often called superbugs.
These have been linked to 23,000 deaths and 2 million illnesses every year in the United States, and up to $20 billion in direct healthcare costs.
"The drug is also effective against pseudomonas, a difficult to treat pathogen," Cantor Fitzgerald analyst Irina Koffler told Reuters ahead of the decision.
Zerbaxa was a major driver behind Merck & Co's offer to buy Cubist for $8.4 billion earlier this month.
The approval is significant for Cubist, whose main product, Cubicin, lost patent protection earlier than expected after a federal court invalidated four of its patents.
Zerbaxa is the fourth new antibacterial drug approved by the FDA this year. The agency approved Actavis Plc's Dalvance in May, Cubists' Sivextro in June and The Medicines Co's Orbactiv in August. (1.usa.gov/1CeJqhC)
Cubist has earlier said it expects European approval for Zerbaxa during the second half of 2015.
Zerbaxa is expected to reach peak sales of $1.15 billion in 2023 and will be priced around $5,000-$6,000 per patient, analysts including Koffler said.
However, the drug would be used selectively at first as it will cost more, she added.
"Physicians often prefer to hold new antibiotics in reserve, using them when other options have failed," Needham analyst Alan Carr said.
Zerbaxa also faces competition from several other companies, including AstraZeneca Plc and Actavis Plc. The companies' rival drug is being reviewed by the FDA, which is expected to reach a decision in the first quarter of 2015.
Tetraphase Pharmaceuticals Inc is also developing a drug for complicated intra-abdominal infections and complicated urinary tract infection, but with a lower dosage than that of Cubists'.