百济神州公布其PD-1抗体Tislelizumab治疗霍奇金淋巴瘤中的关键性临床试验初步结果

2018-07-24 MedSci MedSci原创

百济神州Biogene(纳斯达克股票代码:BGNE)是一家处于商业阶段的生物医药公司,专注于开发和商业化治疗癌症的创新分子靶向药物和肿瘤免疫药物。近日公司公布了其PD-1抗体Tslelizumab治疗复发/难治性经典霍奇金淋巴瘤(R/R cHL)中国患者的关键性2期临床试验独立审查的初步结果。

百济神州Biogene(纳斯达克股票代码:BGNE)是一家处于商业阶段的生物医药公司,专注于开发和商业化治疗癌症的创新分子靶向药物和肿瘤免疫药物。近日公司公布了其PD-1抗体Tslelizumab治疗复发/难治性经典霍奇金淋巴瘤(R/R cHL)中国患者的关键性2期临床试验独立审查的初步结果。

百济神州血液学首席医疗官汪来博士表示:"我们很高兴地宣布首个关于Tislelizumab的关键试验的初步结果。尽管进行了短暂的随访,但Tislelizumab除了与其他PD-1抑制剂拥有一致的安全性外,还具有强有力的患者响应率。我们相信这些强劲的结果将支持我们在今年晚些时候在中国申报Tislelizumab。"

Tislelizumab的单臂关键试验纳入了70例cHL患者,这些患者是自体干细胞移植失败(ASCT)或不符合ASCT资格。主要终点是Lugano 2014标准定义的总体响应率(ORR),次要终点包括无进展生存期(PFS)、反应持续时间(DOR)、完全反应(CR)率、反应时间、安全性和耐受性。截至数据截点为止,中位随访时间约为6.0个月。独立审查委员会于2018年6月提供的审查结果证明:ORR为73%,包括50%的CR,中位缓解持续时间尚未达到。不良事件的频率和严重程度通常与先前报道的Tislelizumab的1期安全性和耐受性数据一致。在治疗cHL过程中某些免疫相关事件如甲状腺功能减退和发热情况,与之前报道的其他PD-1抗体一致。这些cHL数据以及来自临床试验的其他后续数据,预计将包含在百济神州的生物制剂许可证申请(BLA)中。该试验的全部结果预计将在即将举行的医学会议上公布。

Tislelizumab在治疗其他恶性肿瘤的全球3期试验中也正在进行中,包括非小细胞肺癌,肝细胞癌和食道鳞状细胞癌;以及在先前治疗的肝细胞癌或R/R成熟T细胞和NK细胞淋巴瘤患者中进行的两项全球2期临床试验,和另外一项尿路上皮癌的关键性中国2期临床试验。

经典霍奇金淋巴瘤是两种主要类型的淋巴瘤之一,病发于淋巴系统淋巴结,以颈部淋巴结和锁骨上淋巴结常见,然后扩散到其他淋巴结,晚期可侵犯血管,累及脾、肝、骨髓和消化道。根据淋巴瘤研究基金会,霍奇金淋巴瘤不如非霍奇金淋巴瘤常见,2012年中国大约有2,100例确诊的霍奇金淋巴瘤病例。虽然该癌症在儿童和成人中都可能发生,但更多的还是诊断于15-35岁的年轻人和50岁以上的老年人。

Tislelizumab(BGB-A317)是一种在研的人源化单克隆抗体,属于免疫检查点抑制剂的免疫肿瘤学药物,北京百济神州的科学家研发将其用于与PD-1结合,从而阻断其对T细胞的抑制作用。Tislelizumab已显示出对PD-1的高亲和力和特异性,百济神州正在开发将其作为单一疗法并与其他疗法组合,用于治疗广泛的实体瘤和血液癌症。

原始出处:


此文系梅斯医学(MedSci)原创整理编译,转载需授权!

版权声明:
本网站所有内容来源注明为“梅斯医学”或“MedSci原创”的文字、图片和音视频资料,版权均属于梅斯医学所有。非经授权,任何媒体、网站或个人不得转载,授权转载时须注明来源为“梅斯医学”。其它来源的文章系转载文章,或“梅斯号”自媒体发布的文章,仅系出于传递更多信息之目的,本站仅负责审核内容合规,其内容不代表本站立场,本站不负责内容的准确性和版权。如果存在侵权、或不希望被转载的媒体或个人可与我们联系,我们将立即进行删除处理。
在此留言
评论区 (5)
#插入话题
  1. [GetPortalCommentsPageByObjectIdResponse(id=1912007, encodeId=bb76191200e42, content=<a href='/topic/show?id=4de7112046c' target=_blank style='color:#2F92EE;'>#mAb#</a>, beContent=null, objectType=article, channel=null, level=null, likeNumber=41, replyNumber=0, topicName=null, topicId=null, topicList=[TopicDto(id=11204, encryptionId=4de7112046c, topicName=mAb)], attachment=null, authenticateStatus=null, createdAvatar=, createdBy=25e7304, createdName=snf701207, createdTime=Wed Jul 03 23:09:00 CST 2019, time=2019-07-03, status=1, ipAttribution=), GetPortalCommentsPageByObjectIdResponse(id=1344994, encodeId=8d5b134499490, content=<a href='/topic/show?id=cf721640495' target=_blank style='color:#2F92EE;'>#SLE#</a>, beContent=null, objectType=article, channel=null, level=null, likeNumber=34, replyNumber=0, topicName=null, topicId=null, topicList=[TopicDto(id=16404, encryptionId=cf721640495, topicName=SLE)], attachment=null, authenticateStatus=null, createdAvatar=http://thirdwx.qlogo.cn/mmopen/vi_32/kbRUeosenzlejlNGWXdWjSYhBKL1QYGQwfehJOkMXHiavh5wl7pKeju5Kcxdvr50ic6FWML3x6NMCxhG1bOaVjyA/132, createdBy=20872500216, createdName=ms4657536712156177, createdTime=Thu Jul 26 03:09:00 CST 2018, time=2018-07-26, status=1, ipAttribution=), GetPortalCommentsPageByObjectIdResponse(id=1577093, encodeId=c8c515e709368, content=<a href='/topic/show?id=a2a613914cd' target=_blank style='color:#2F92EE;'>#PD-1抗体#</a>, beContent=null, objectType=article, channel=null, level=null, likeNumber=46, replyNumber=0, topicName=null, topicId=null, topicList=[TopicDto(id=13914, encryptionId=a2a613914cd, topicName=PD-1抗体)], attachment=null, authenticateStatus=null, createdAvatar=, createdBy=4c37265, createdName=hb2008ye, createdTime=Thu Jul 26 03:09:00 CST 2018, time=2018-07-26, status=1, ipAttribution=), GetPortalCommentsPageByObjectIdResponse(id=334056, encodeId=5f8133405657, content=学习, beContent=null, objectType=article, channel=null, level=null, likeNumber=92, replyNumber=0, topicName=null, topicId=null, topicList=[], attachment=null, authenticateStatus=null, createdAvatar=https://wx.qlogo.cn/mmopen/mStl88fu4NfBfgWn9nXBgH1sNSiaOAKhsKpN40jDHQKqcRzovau5VibLvREN8uxnu9sKoScBicHSiaDMmbveibFdrBiaD4k4IOPwlG/0, createdBy=b5d11730951, createdName=Jackie Li, createdTime=Wed Jul 25 11:29:59 CST 2018, time=2018-07-25, status=1, ipAttribution=), GetPortalCommentsPageByObjectIdResponse(id=333877, encodeId=b8ba3338e7fe, content=好消息, beContent=null, objectType=article, channel=null, level=null, likeNumber=86, replyNumber=0, topicName=null, topicId=null, topicList=[], attachment=null, authenticateStatus=null, createdAvatar=, createdBy=82311653708, createdName=医者仁心5538, createdTime=Tue Jul 24 14:13:18 CST 2018, time=2018-07-24, status=1, ipAttribution=)]
    2019-07-03 snf701207
  2. [GetPortalCommentsPageByObjectIdResponse(id=1912007, encodeId=bb76191200e42, content=<a href='/topic/show?id=4de7112046c' target=_blank style='color:#2F92EE;'>#mAb#</a>, beContent=null, objectType=article, channel=null, level=null, likeNumber=41, replyNumber=0, topicName=null, topicId=null, topicList=[TopicDto(id=11204, encryptionId=4de7112046c, topicName=mAb)], attachment=null, authenticateStatus=null, createdAvatar=, createdBy=25e7304, createdName=snf701207, createdTime=Wed Jul 03 23:09:00 CST 2019, time=2019-07-03, status=1, ipAttribution=), GetPortalCommentsPageByObjectIdResponse(id=1344994, encodeId=8d5b134499490, content=<a href='/topic/show?id=cf721640495' target=_blank style='color:#2F92EE;'>#SLE#</a>, beContent=null, objectType=article, channel=null, level=null, likeNumber=34, replyNumber=0, topicName=null, topicId=null, topicList=[TopicDto(id=16404, encryptionId=cf721640495, topicName=SLE)], attachment=null, authenticateStatus=null, createdAvatar=http://thirdwx.qlogo.cn/mmopen/vi_32/kbRUeosenzlejlNGWXdWjSYhBKL1QYGQwfehJOkMXHiavh5wl7pKeju5Kcxdvr50ic6FWML3x6NMCxhG1bOaVjyA/132, createdBy=20872500216, createdName=ms4657536712156177, createdTime=Thu Jul 26 03:09:00 CST 2018, time=2018-07-26, status=1, ipAttribution=), GetPortalCommentsPageByObjectIdResponse(id=1577093, encodeId=c8c515e709368, content=<a href='/topic/show?id=a2a613914cd' target=_blank style='color:#2F92EE;'>#PD-1抗体#</a>, beContent=null, objectType=article, channel=null, level=null, likeNumber=46, replyNumber=0, topicName=null, topicId=null, topicList=[TopicDto(id=13914, encryptionId=a2a613914cd, topicName=PD-1抗体)], attachment=null, authenticateStatus=null, createdAvatar=, createdBy=4c37265, createdName=hb2008ye, createdTime=Thu Jul 26 03:09:00 CST 2018, time=2018-07-26, status=1, ipAttribution=), GetPortalCommentsPageByObjectIdResponse(id=334056, encodeId=5f8133405657, content=学习, beContent=null, objectType=article, channel=null, level=null, likeNumber=92, replyNumber=0, topicName=null, topicId=null, topicList=[], attachment=null, authenticateStatus=null, createdAvatar=https://wx.qlogo.cn/mmopen/mStl88fu4NfBfgWn9nXBgH1sNSiaOAKhsKpN40jDHQKqcRzovau5VibLvREN8uxnu9sKoScBicHSiaDMmbveibFdrBiaD4k4IOPwlG/0, createdBy=b5d11730951, createdName=Jackie Li, createdTime=Wed Jul 25 11:29:59 CST 2018, time=2018-07-25, status=1, ipAttribution=), GetPortalCommentsPageByObjectIdResponse(id=333877, encodeId=b8ba3338e7fe, content=好消息, beContent=null, objectType=article, channel=null, level=null, likeNumber=86, replyNumber=0, topicName=null, topicId=null, topicList=[], attachment=null, authenticateStatus=null, createdAvatar=, createdBy=82311653708, createdName=医者仁心5538, createdTime=Tue Jul 24 14:13:18 CST 2018, time=2018-07-24, status=1, ipAttribution=)]
  3. [GetPortalCommentsPageByObjectIdResponse(id=1912007, encodeId=bb76191200e42, content=<a href='/topic/show?id=4de7112046c' target=_blank style='color:#2F92EE;'>#mAb#</a>, beContent=null, objectType=article, channel=null, level=null, likeNumber=41, replyNumber=0, topicName=null, topicId=null, topicList=[TopicDto(id=11204, encryptionId=4de7112046c, topicName=mAb)], attachment=null, authenticateStatus=null, createdAvatar=, createdBy=25e7304, createdName=snf701207, createdTime=Wed Jul 03 23:09:00 CST 2019, time=2019-07-03, status=1, ipAttribution=), GetPortalCommentsPageByObjectIdResponse(id=1344994, encodeId=8d5b134499490, content=<a href='/topic/show?id=cf721640495' target=_blank style='color:#2F92EE;'>#SLE#</a>, beContent=null, objectType=article, channel=null, level=null, likeNumber=34, replyNumber=0, topicName=null, topicId=null, topicList=[TopicDto(id=16404, encryptionId=cf721640495, topicName=SLE)], attachment=null, authenticateStatus=null, createdAvatar=http://thirdwx.qlogo.cn/mmopen/vi_32/kbRUeosenzlejlNGWXdWjSYhBKL1QYGQwfehJOkMXHiavh5wl7pKeju5Kcxdvr50ic6FWML3x6NMCxhG1bOaVjyA/132, createdBy=20872500216, createdName=ms4657536712156177, createdTime=Thu Jul 26 03:09:00 CST 2018, time=2018-07-26, status=1, ipAttribution=), GetPortalCommentsPageByObjectIdResponse(id=1577093, encodeId=c8c515e709368, content=<a href='/topic/show?id=a2a613914cd' target=_blank style='color:#2F92EE;'>#PD-1抗体#</a>, beContent=null, objectType=article, channel=null, level=null, likeNumber=46, replyNumber=0, topicName=null, topicId=null, topicList=[TopicDto(id=13914, encryptionId=a2a613914cd, topicName=PD-1抗体)], attachment=null, authenticateStatus=null, createdAvatar=, createdBy=4c37265, createdName=hb2008ye, createdTime=Thu Jul 26 03:09:00 CST 2018, time=2018-07-26, status=1, ipAttribution=), GetPortalCommentsPageByObjectIdResponse(id=334056, encodeId=5f8133405657, content=学习, beContent=null, objectType=article, channel=null, level=null, likeNumber=92, replyNumber=0, topicName=null, topicId=null, topicList=[], attachment=null, authenticateStatus=null, createdAvatar=https://wx.qlogo.cn/mmopen/mStl88fu4NfBfgWn9nXBgH1sNSiaOAKhsKpN40jDHQKqcRzovau5VibLvREN8uxnu9sKoScBicHSiaDMmbveibFdrBiaD4k4IOPwlG/0, createdBy=b5d11730951, createdName=Jackie Li, createdTime=Wed Jul 25 11:29:59 CST 2018, time=2018-07-25, status=1, ipAttribution=), GetPortalCommentsPageByObjectIdResponse(id=333877, encodeId=b8ba3338e7fe, content=好消息, beContent=null, objectType=article, channel=null, level=null, likeNumber=86, replyNumber=0, topicName=null, topicId=null, topicList=[], attachment=null, authenticateStatus=null, createdAvatar=, createdBy=82311653708, createdName=医者仁心5538, createdTime=Tue Jul 24 14:13:18 CST 2018, time=2018-07-24, status=1, ipAttribution=)]
  4. [GetPortalCommentsPageByObjectIdResponse(id=1912007, encodeId=bb76191200e42, content=<a href='/topic/show?id=4de7112046c' target=_blank style='color:#2F92EE;'>#mAb#</a>, beContent=null, objectType=article, channel=null, level=null, likeNumber=41, replyNumber=0, topicName=null, topicId=null, topicList=[TopicDto(id=11204, encryptionId=4de7112046c, topicName=mAb)], attachment=null, authenticateStatus=null, createdAvatar=, createdBy=25e7304, createdName=snf701207, createdTime=Wed Jul 03 23:09:00 CST 2019, time=2019-07-03, status=1, ipAttribution=), GetPortalCommentsPageByObjectIdResponse(id=1344994, encodeId=8d5b134499490, content=<a href='/topic/show?id=cf721640495' target=_blank style='color:#2F92EE;'>#SLE#</a>, beContent=null, objectType=article, channel=null, level=null, likeNumber=34, replyNumber=0, topicName=null, topicId=null, topicList=[TopicDto(id=16404, encryptionId=cf721640495, topicName=SLE)], attachment=null, authenticateStatus=null, createdAvatar=http://thirdwx.qlogo.cn/mmopen/vi_32/kbRUeosenzlejlNGWXdWjSYhBKL1QYGQwfehJOkMXHiavh5wl7pKeju5Kcxdvr50ic6FWML3x6NMCxhG1bOaVjyA/132, createdBy=20872500216, createdName=ms4657536712156177, createdTime=Thu Jul 26 03:09:00 CST 2018, time=2018-07-26, status=1, ipAttribution=), GetPortalCommentsPageByObjectIdResponse(id=1577093, encodeId=c8c515e709368, content=<a href='/topic/show?id=a2a613914cd' target=_blank style='color:#2F92EE;'>#PD-1抗体#</a>, beContent=null, objectType=article, channel=null, level=null, likeNumber=46, replyNumber=0, topicName=null, topicId=null, topicList=[TopicDto(id=13914, encryptionId=a2a613914cd, topicName=PD-1抗体)], attachment=null, authenticateStatus=null, createdAvatar=, createdBy=4c37265, createdName=hb2008ye, createdTime=Thu Jul 26 03:09:00 CST 2018, time=2018-07-26, status=1, ipAttribution=), GetPortalCommentsPageByObjectIdResponse(id=334056, encodeId=5f8133405657, content=学习, beContent=null, objectType=article, channel=null, level=null, likeNumber=92, replyNumber=0, topicName=null, topicId=null, topicList=[], attachment=null, authenticateStatus=null, createdAvatar=https://wx.qlogo.cn/mmopen/mStl88fu4NfBfgWn9nXBgH1sNSiaOAKhsKpN40jDHQKqcRzovau5VibLvREN8uxnu9sKoScBicHSiaDMmbveibFdrBiaD4k4IOPwlG/0, createdBy=b5d11730951, createdName=Jackie Li, createdTime=Wed Jul 25 11:29:59 CST 2018, time=2018-07-25, status=1, ipAttribution=), GetPortalCommentsPageByObjectIdResponse(id=333877, encodeId=b8ba3338e7fe, content=好消息, beContent=null, objectType=article, channel=null, level=null, likeNumber=86, replyNumber=0, topicName=null, topicId=null, topicList=[], attachment=null, authenticateStatus=null, createdAvatar=, createdBy=82311653708, createdName=医者仁心5538, createdTime=Tue Jul 24 14:13:18 CST 2018, time=2018-07-24, status=1, ipAttribution=)]
    2018-07-25 Jackie Li

    学习

    0

  5. [GetPortalCommentsPageByObjectIdResponse(id=1912007, encodeId=bb76191200e42, content=<a href='/topic/show?id=4de7112046c' target=_blank style='color:#2F92EE;'>#mAb#</a>, beContent=null, objectType=article, channel=null, level=null, likeNumber=41, replyNumber=0, topicName=null, topicId=null, topicList=[TopicDto(id=11204, encryptionId=4de7112046c, topicName=mAb)], attachment=null, authenticateStatus=null, createdAvatar=, createdBy=25e7304, createdName=snf701207, createdTime=Wed Jul 03 23:09:00 CST 2019, time=2019-07-03, status=1, ipAttribution=), GetPortalCommentsPageByObjectIdResponse(id=1344994, encodeId=8d5b134499490, content=<a href='/topic/show?id=cf721640495' target=_blank style='color:#2F92EE;'>#SLE#</a>, beContent=null, objectType=article, channel=null, level=null, likeNumber=34, replyNumber=0, topicName=null, topicId=null, topicList=[TopicDto(id=16404, encryptionId=cf721640495, topicName=SLE)], attachment=null, authenticateStatus=null, createdAvatar=http://thirdwx.qlogo.cn/mmopen/vi_32/kbRUeosenzlejlNGWXdWjSYhBKL1QYGQwfehJOkMXHiavh5wl7pKeju5Kcxdvr50ic6FWML3x6NMCxhG1bOaVjyA/132, createdBy=20872500216, createdName=ms4657536712156177, createdTime=Thu Jul 26 03:09:00 CST 2018, time=2018-07-26, status=1, ipAttribution=), GetPortalCommentsPageByObjectIdResponse(id=1577093, encodeId=c8c515e709368, content=<a href='/topic/show?id=a2a613914cd' target=_blank style='color:#2F92EE;'>#PD-1抗体#</a>, beContent=null, objectType=article, channel=null, level=null, likeNumber=46, replyNumber=0, topicName=null, topicId=null, topicList=[TopicDto(id=13914, encryptionId=a2a613914cd, topicName=PD-1抗体)], attachment=null, authenticateStatus=null, createdAvatar=, createdBy=4c37265, createdName=hb2008ye, createdTime=Thu Jul 26 03:09:00 CST 2018, time=2018-07-26, status=1, ipAttribution=), GetPortalCommentsPageByObjectIdResponse(id=334056, encodeId=5f8133405657, content=学习, beContent=null, objectType=article, channel=null, level=null, likeNumber=92, replyNumber=0, topicName=null, topicId=null, topicList=[], attachment=null, authenticateStatus=null, createdAvatar=https://wx.qlogo.cn/mmopen/mStl88fu4NfBfgWn9nXBgH1sNSiaOAKhsKpN40jDHQKqcRzovau5VibLvREN8uxnu9sKoScBicHSiaDMmbveibFdrBiaD4k4IOPwlG/0, createdBy=b5d11730951, createdName=Jackie Li, createdTime=Wed Jul 25 11:29:59 CST 2018, time=2018-07-25, status=1, ipAttribution=), GetPortalCommentsPageByObjectIdResponse(id=333877, encodeId=b8ba3338e7fe, content=好消息, beContent=null, objectType=article, channel=null, level=null, likeNumber=86, replyNumber=0, topicName=null, topicId=null, topicList=[], attachment=null, authenticateStatus=null, createdAvatar=, createdBy=82311653708, createdName=医者仁心5538, createdTime=Tue Jul 24 14:13:18 CST 2018, time=2018-07-24, status=1, ipAttribution=)]
    2018-07-24 医者仁心5538

    好消息

    0

相关资讯

CLIN CANCER RES:PD-1阻断和CD27活化可以协同增强CD8+T细胞抗肿瘤活性

PD-1免疫检查点抑制是肿瘤免疫治疗领域具有革命性的突破,但是有反应的患者比例较低,原因与活化DC细胞较少导致的T细胞不完全激活有关。DC信号可以通过CD27激动剂增强,CLIN CANCER RES近期发表了一篇文章,研究联合CD27激动性抗体是否可以增强抗PD-1/L1的疗效。

CLIN CANCER RES:CD103+肿瘤定植CD8+T细胞与黑色素瘤患者接受抗PD-1治疗预后改善有关

免疫检查点抑制疗法为肿瘤治疗带来了革命。但是只有不到一半的接受治疗的患者出现持续缓解。由于缺少对启动抗肿瘤免疫反应的细胞特征的理解,如何改善治疗效果也一直并不明确。CLIN CANCER RES近期发表了一篇文章研究这一问题。

信达生物PD-1单抗霍奇金淋巴瘤关键II期研究数据公布:客观缓解率近80%

5月17日,信达生物公布了其PD-1单抗信迪利单抗(IBI308)用于治疗复发/难治性霍奇金淋巴瘤治疗的关键性ORIENT-1研究的结果。

Blood:霍奇金淋巴瘤肿瘤微环境中,CD4+效应T细胞耗竭、调节T细胞富集

中心点:新确诊的原发性cHLs伴随CD4+Th1极化调节T细胞和分化的效应T细胞增多。原发性cHLs表现出两种主要的免疫抑制互补——PD-1+Th1效应细胞耗竭和PD-1-Th1调节T细胞活化。摘要:经典型霍奇金淋巴瘤(cHL)患者抗肿瘤免疫反应失效。霍奇金RS(HRS)细胞有多种逃脱免疫细胞的机制,包括9p24.1/CD274(PD-L1)/PDCD1LG2(PD-L2)遗传变异、PD-1配体过

Nat Immunol:PD-1/PD-L1不响应机制被揭密,NK细胞其核心作用

本周二,国际顶级期刊《自然免疫学》刊登了中国科学技术大学田志刚、孙汭(rui)教授课题组的重要研究成果[2]。他们的研究成果在一定程度上解释了为什么有些患者对目前的免疫检查点抑制剂治疗不响应;更重要的是,他们的研究成果有望大幅扩大免疫检查点抑制剂适用的患者群体。本研究的第一作者是张清博士。 伴随研究论文同期发表的评论性文章给予该研究非常高的评价,“检查点抑制剂:自然杀伤(

Cell Rep:大开眼界!肿瘤细胞竟是这样躲过免疫治疗的!

目前,以PD-1/PD-L1抑制剂为主的免疫疗法已成为肿瘤治疗领域的绝对热门,但是,PD-1 /PD-L1抑制剂在不同类型肿瘤病人中应用后,其效果却因人而异。科学家们曾认为这是受制于患者肿瘤细胞PD-L1的表达水平,然而,随着对PD-1 /PD-L1抑制剂疗法的深入研究,研究人员发现部分患者即使表达了高水平的PD-L1,PD-1 /PD-L1抑制剂仍无法有效治疗肿瘤。这是为什么呢?