2014年11月3日讯 /生物谷BIOON/ --继2天前获得FDA内部审查员的肯定，第一三共制药（Daiichi Sankyo）新型口服抗凝血剂—Xa因子抑制剂edoxaban，近日又获得了FDA专家委员会的一致肯定，双方都支持批准edoxaban用于房颤（AF）患者预防中风，大大提高了赢得FDA批准的可能性。edoxaban是每日口服一次的抗凝血剂，通过抑制凝血因子Xa发挥作用。目前，第一三共正在调查edoxaban用于房颤患者预防中风。
FDA心血管和肾脏药物顾问委员会(CRDAC)以9比1的投票结果，认为edoxaban用于房颤患者预防中风的临床益处大于该药的风险，支持批准edoxaban。另外，有3个小组成员建议批准edoxaban仅用于肾功能异常患者群体，这一点与FDA内部审查员的意见一致，但大多数成员站在了第一三共一方，支持批准edoxaban同时用于肾功能正常和异常患者群体。
此前，FDA内部审查员认为，60mg剂量edoxaban在轻度肾功能受损的患者群体中疗效明显优于广泛使用的抗凝血剂老药华法林（warfarin），但在肾功能正常的患者群体中的药物副作用也非常明显。总的研究数据支持了edoxaban的有效性，但基线肾功能（baseline renal function）疗效预后可能潜在影响edoxaban的批准或药物标签。
FDA已指定edoxaban处方药用户收费法（PUDFA）目标日期为2015年1月8日。FDA在做出最终审查决定时，通常都会采纳顾问委员会的建议。
如果获批，edoxaban将以品牌名Savaysa上市，同时将与市面上的其他同类产品展开竞争，头号对手是拜耳和强生的拜瑞妥（Xarelto，rivaroxban），其次是百时美和辉瑞的Eliquis（apixaban，阿哌沙班）以及勃林格殷格翰的Pradaxa（dabigatran，达比加群）。edoxaban和Xarelto均每日口服一次，Eliquis和Pradaxa每日口服2次。
华法林上市已超过半个世纪，能够有效预防中风，但该药的使用必须监测血药浓度、剂量调整及饮食限制。分析师预计，华法林替代产品的市场规模每年高达100亿美元。
除了房颤适应症，监管部门也正在审查edoxaban治疗静脉血栓栓塞（VTE）的上市申请。edoxaban于2011年4月在日本上市，品牌名为Lixiana，用于预防骨科大手术后静脉血栓栓塞（VTE）。在其他地理区域，包括欧洲和美国，edoxaban正处于III期临床开发。
edoxaban是一种实验性、口服、每日一次的抗凝血剂，能够可逆性抑制凝血因子Xa。全球性edoxaban临床项目包括2个III期研究：Hokusai-VTE和ENGAGE AF-TIMI48。前者在深静脉血栓（DVT）和/或肺栓塞（PE）患者中开展，评价edoxaban对症状性静脉血栓栓塞（VTE）复发的治疗和预防。后者在非瓣膜性心房颤动（AF）患者中开展，评价edoxaban对中风和全身性栓塞事件（SEE）的预防。
英文原文：FDA panel backs Daiichi's blood thinner
(Reuters) - A panel of advisers to the U.S. Food and Drug Administration voted 9-1 in favor of approving Japanese drugmaker Daiichi Sankyo Co's blood thinner for use in some patients with atrial fibrillation.
The drug, edoxaban, is a once-daily anticoagulant that inhibits Factor Xa, a protein that plays a central role in blood-clotting. If approved, it would compete with three other medicines already vying to displace a decades-old treatment.
Edoxaban is a potential treatment for non-valvular atrial fibrillation, a particular form of a condition characterized by a rapid, irregular heartbeat that is often the cause of strokes.
According to late-stage trial data submitted by Daiichi, the drug is as effective - and safer than - warfarin, an anticoagulant that has been on the market for more than half a century.
While effective in preventing strokes, warfarin's use requires blood-level monitoring, dose adjustments and dietary restrictions.
Edoxaban could compete with Xarelto, sold by Bayer AG and Johnson & Johnson; Eliquis, sold by Bristol-Myers Squibb Co and Pfizer Inc, and Pradaxa, made by privately held Boehringer Ingelheim.
Despite the overwhelmingly positive vote, the advisers on the panel were divided over whether edoxaban should be used in all patients, or limited to those with impaired kidney function.
On Tuesday, FDA staff reviewers recommended limiting use of the drug to renally impaired patients - a decision based on subgroup data that showed a 60 mg dose was "almost significantly worse" than warfarin in patients with normal kidney function.
The FDA is not obligated to follow the recommendations of its advisory panels, although it typically does so.
Savaysa, the proposed brand name for edoxaban in the United States, is also undergoing regulatory review for the treatment of venous thromboembolism (VTE), blood clots that form in the veins.