终极HBV Cure之七种武器

HBVCURER

ivanich 发表于 2015-10-21 17:11
大神，期待你讲神秘的古巴疫苗！

古巴疫苗其实没啥神秘的，其技术核心是HBsAg和HBcAg形成类病毒颗粒（VLP），比传统方式制备的抗原的免疫原性更强。根据现有数据看，和乙克大致在一个水平上，至少没有显著的强（数据有限，很难直接比较，所以我拿干扰素做中间体）。大多数朋友看不上乙克，其实无论从理念到实践，都是可圈可点的。

对于HBsAg载量比较低的患者，我相信无论打古巴疫苗还是乙克，都能够得到较好的效果，而HBsAg载量很高的患者，两者的效果都很难理想。还会有一些其他的患者自身的宿主因子制约着治疗性疫苗的效果，据我所知乙克正在做相关的工作，通过在注射前检测体内一些相应的细胞因子指标，预测该患者是否会对疫苗有很好应答，帮助筛选适合的患者人群达到更理想的效果。这也是目前正在开展的三期B临床实验的目标之一。

总之，古巴疫苗不是神药，但如果能通过少数几次注射即达到干扰素长期治疗的效果的话，也是很大的进步了，期待其三期临床的数据。

StephenW

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乙克有一个弱点 - 没有核心抗原(HbcAg).

newchinabok

手中武器越多越好，再优化治疗方案

HBVCURER

StephenW 发表于 2015-10-21 18:25
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乙克有一个弱点 - 没有核心抗原(HbcAg).

如果没有核心抗原，但是却能和有核心抗原的疫苗效果差不多，说明什么问题？

对于药物/疫苗而言，在保证疗效的前提下，组分越少越好；同样的，如果能单药解决问题，那就绝不要联合治疗。联合治疗是没有办法的办法，联合治疗也要致力于使用尽量少的药物，而不是越多越好。

当然，很可能乙克在加入核心抗原后能达到比现在更好的效果，但我不太清楚他们的研发团队有没有这样的想法和计划。

StephenW

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Treatment Options Beyond IFNα and NUCs for Chronic HBV Infection
Expectations for Tomorrow

G. Baltayiannis, P. Karayiannis

J Viral Hepat. 2014;21(11):753-761.

http://www.medscape.com/viewarticle/833039

I copied extracts from the section on therapeutic vaccines. YIC was mentioned.
"Therapeutic Vaccination

This approach attempts to break tolerance and stimulate T-cell immune responses in chronic HBV carriers, using newly developed vaccines, different adjuvants and by altering the route of administration, as licensed vaccines failed to do so in the past.[47] A peptide-based T-cell vaccine consisting of a lipopeptide (CY-1899) containing a T-helper epitope from tetanus toxoid and a CTL epitope from HBV core (aa 18–27) had a similar fate when tested in chronic HBV carriers.[48] An antigen–antibody (HBsAg-HBIG) immunogenic complex with alum as adjuvant (YIC) tested in a phase III clinical trial of 450 chronic HBV was effective at precipitating seroconversion in only 14.0% of patients after 12 injections as opposed to 21.9% in the alum control group.[49]

A vaccine comprising particulate HBsAg and HBcAg with the saponin-based IscomatrixR (CSL Behring, Kankakee, IL, USA) adjuvant was tested in C57BL/6 mice for its ability to stimulate T- and B-cell responses and to break tolerance in HBV transgenic mice. The vaccine induced multifunctional HBsAg- and HBcAg-specific CD8+ T cell and high titre antibody responses against both antigens in both animal groups, as well as anti-HBs seroconversion 2 weeks postinjection in the latter group.[50] In another approach, recombinant S and/or C proteins with polyphosphazene and/or CpG as adjuvants tested in transgenic mice were only capable of breaking tolerance in low viraemic mice.[51] A phase III clinical trial with a vaccine containing both HBsAg and HBcAg administered by a nasal vaccine device once every 2 weeks for five times was compared to Peg-IFN treatment in chronic HBV carriers. 37/75 patients who received the vaccine were HBV-DNA negative after the fifth vaccine dose, almost comparable to those negative after 48 weeks of Peg-IFN treatment.[52] It remains to be seen, however, whether the vaccine response was durable and accompanied by HBs seroconversion.

Finally, GS-4774 is a yeast-based vaccine (Tarmogen) expressing a chimeric protein comprising 60 amino acids from the X protein, as well as the entire L-HBsAg and core proteins. A Phase I study in healthy volunteers indicated that three doses of 10 yeast units given monthly were well tolerated and elicited HBV-specific immune responses.[53]
Other Approaches

Alum-based vaccines, such as the current HBV vaccine, promote production of antibodies and a Th2-biased immune response. For effective therapeutic vaccination, however, both humoral and cytotoxic T-cell responses may be necessary to eradicate infected cells. Immunization of transgenic animals with an HBsAg vaccine supplemented with a CpG oligonucleotide as adjuvant led to the clearance of serum HBsAg and development of anti-HBs, with concurrent down-regulation of HBV mRNA production in the liver. Adoptive transfer experiments of T cells from such animals showed that they were able to partially control transgene expression in the liver and sera of recipient transgenic mice were clear of HBsAg, without an antibody requirement.[54] A CpG containing HBsAg vaccine was shown to overcome hyporesponsiveness normally seen in immunized orangutans.[55] Finally, long-term treatment of transgenic mice with siRNAs targeting the C and S regions produced detectable anti-HBs after normal vaccination combined with concurrent CpG injection.[56] Whether similar responses are observed in human trials must await further investigation.

HBV subviral particles together with LPS as a co-activating molecule were used to pulse and activate dendritic cells (DC) in vitro. HBV transgenic mice injected with such DC on two occasions appeared to develop strong HBV-specific antibody and T-cell responses, which, however, were unable to control HBsAg or HBV-DNA levels.[57] DC isolated from chronic HBV carriers and stimulated with the HBV vaccine were injected back, half of them hypodermically and the other half IV, every 2 weeks for 12 times. The patients were on lamivudine treatment at the same time and thymosin a1 was injected twice weekly. However, disappointingly, the overall HBeAg seroconversion rate was only 16%.[58] In another study, stimulation of PBMCs or liver-infiltrating lymphocytes from HLA-A × 0201(+) chronic HBV patients by HBc peptide-loaded plasmacytoid DCs elicited HBV-specific CD8+ T-cell responses, which were undermined by circulating HBeAg levels.[59] Unexpectedly, vaccination of transgenic mice with HBsAg-pulsed DC induced HBsAg-specific immunity, but failed to do so against HBcAg. In contrast, immunization with HBcAg-pulsed DC resulted in HBsAg negativity, seroconversion to anti-HBs, and development of HBsAg- and HBcAg-specific T cells and CTL in the spleen and the liver.[60] It seems therefore that HBcAg should be an integral component of any future therapeutic vaccine against HBV."

The above bold and underlined is by me, no the authors. This has been drawn to the attention of Professor Wen.

P.S. The fate of GS4774 is unknown as it failed its clinical trial's expectation.

MP4

HBVCURER 发表于 2015-10-21 18:38
如果没有核心抗原，但是却能和有核心抗原的疫苗效果差不多，说明什么问题？

对于药物/疫苗而言，在保证 ...

乙克有二代

HBVCURER

StephenW 发表于 2015-10-21 18:58
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Treatment Options Beyond IFNα and NUCs for Chronic HBV Infection

对于HBV治疗性疫苗而言，使用何种抗原使用何种表达体系使用何种治疗流程目前仍然是没有答案的探索。目前已知的是，在动物模型尤其是小鼠模型中的结果几乎无法预测在人体实验的效果，这也是目前治疗性疫苗研发中所面临的主要困境，不仅仅是针对HBV，所有的治疗性疫苗都面临同样的问题，成功的先例几乎没有。

GS4774的“失败”给所有基于蛋白免疫的治疗性疫苗泼了一盆冷水，DNA疫苗和病毒载体疫苗眼下也成为某些公司研发的主要方向。我个人（但不仅仅是我一个人）的感觉是，未来治愈乙肝，如果联合治疗势在必行的话，那么很可能作为最后一枪的治疗性疫苗使用什么样的抗原组合其实不那么关键。乙克三期临床发现，有相当一部分患者，仅仅单纯注射疫苗佐剂（免疫增强效果）而不使用任何乙肝抗原，同样能达到很好的治疗效果。这类数据比任何动物实验结果都有价值的多。

换句话说，在联合治疗中，如果前期病毒复制被成功抑制，同时降低HBsAg成功消除免疫耐受环境，那么在最后一个环节是使用干扰素，还是治疗性疫苗，还是类似GS9620这样的小分子免疫激活剂，可能都不会有太大的差别。

ivanich

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尼玛，真是大神啊！

hchu

“病毒复制成功抑制，降低HBsAg成功消除免疫耐受环境，最后使用干扰素，或治疗性疫苗，或GS9620一类的小分子免疫激活剂……",可能在不远的将来被写入乙肝治疗指南。

zgct

今天我也是闲的发慌了。。。这是在网友@zhaoyun810提供的材料中扒出来的一篇2015肝病大会基于ARC-520二期临床数据的研究报告，为了尽量不弄错，也查了很多资料，注解中也有各位关心的所谓降低多少log是什么意思的问题。另外，欢迎转载，但请注明出处。
本研究报告的第一作者是香港大学的Man-Fung Yuen，因为精力问题，就直接将各位作者及单位贴上了，以表示对知识产权的尊重。
Title：ARC-520 produces deep and durable knockdown of viralantigens and DNA in a phase II study in patients with chronic hepatitis B
标题：慢乙患者中进行的ARC-520产品深入并持续性降低病毒抗原与DNA的临床二期研究
作者及单位：
Man-Fung Yuen1, Henry Lik-Yuen Chan2, Sze HangKevin Liu1, Bruce Given3, Thomas Schluep3, James Hamilton3, Ching-Lung Lai1,Stephen Locarnini4, Johnson Y. Lau5, Carlo Ferrari6, Robert Gish7,8;
1The University of Hong Kong, Hong Kong, China;
2The Chinese University of Hong Kong, HongKong, China;
3Arrow-head Research Corp., Pasadena, CA;
4Victorian Infectious Dis-eases ReferenceLaboratory, Melbourne, VIC, Australia;
5Hong Kong Polytechnic University, Hong Kong,China;
6University of Parma, Parma, Italy;
7Stanford University, Palo Alto, CA;
8Hepatitis B Foundation, Doylestown, PA
Chronic hepatitis B(CHB) has become an important target for drug development. ARC-520 (ARC), thefirst RNA interference-based drug to reach patients(pts), targets ccc-DNA-derived mRNA; herein we report results in CHB.
背景：慢性乙肝已经成为药物开发的一个重要目标。ARC-520，首个基于RNA干扰的药物以衍生自共价闭合环状DNA的信使RNA为靶向。（注1：reach patient字面意思是“病患可以接触到”，我猜这里是指针对病人或用于治疗的意思吧；注2：cccDNA是医学术语，在互动百科可以查知，只有消除了细胞核内的cccDNA才能彻底消除乙肝患者的病毒携带状态，是抗病毒治疗的目的。不知道这里可否理解为彻底清除病毒，表抗转阴之类的）

Methods: 58 CHB pts (48 ARC,10 placebo (PL), mean age 41 yrs (range 23-59) were included. 38 pts wereHBeAg-neg and 20 HBeAg-pos. At entry, 32of 38 HBeAg-neg and 14 of 20 HBeAg-poshad taken entecavir (ETV) for mean of 5 yrs (range 2-8) and were on ETVthroughout the study. 12 treatment naïve pts (6 HBeAg-neg, 6 HBeAg-pos) startedon ETV during the trial. All pts received a single dose IV of ARC or PL (6HBeAg-pos received a divided dose of ARC separated by 2 wks) and had viralparameter knockdown(KD) measured over 85 days [qHBsAg, HB core-related antigen (qHBcrAg) and viralDNA in all, qHBeAg in HBeAg-pos]. Doses were 1-4 mg/kg in HBeAg-neg. AllHBeAg-pos received 4 mg/kg. 15 pts are continuing in follow-up.
方法：本研究包括58位慢性乙肝患者，48位使用ARC-520治疗，10人采用安慰剂，年龄在23-59岁之间，平均年龄为41岁。38位病患的乙肝e抗原为阴性但乙肝表面抗原为阳性。参与研究时，38位e抗原阴性的病患中的32位病患与20位表抗阳性的病患中的14位病患已经开始服用恩替卡韦2-8年不等，平均服药年限是5年，并且在研究期间继续服用恩替卡韦。12位初治患者（6人e抗原阴性，6人e抗原阳性）在试验中开始服用恩替卡韦。（就是说，所有的人都在吃恩替卡韦了）所有的病患接受了单倍剂量的ARC-520或安慰剂的静脉注射（6个e抗原阳性的病患接受了间隔两周的均分剂量的ARC-520的静脉注射），85天后，测量病毒参数的降低情况（在全体病患中进行乙肝表面抗原定量，乙肝核相关抗原定量和病毒DNA定量，在e抗原阳性的病患中进行乙肝e抗原定量）。对e抗原阴性的病患的给药剂量是每公斤体重1-4毫克。所有的e抗原阳性的病患接受每公斤体重4毫克的给药。15个病患持续用药中（就是说在本摘要投稿时，还在治疗）。

Results: ARC therapy was welltolerated - 23%reported a mild or mod adverseevent (AE) with no AE rated serious, severe, drug-related or causing withdrawalfrom the trial. Viral DNA was below level of quantization in all chronic ETVpts at study entry. Naïve pts reduced viral DNA up to 4.3 log (mean 2.2 log)after ARC and ETV. ARC reduced viral antigens with qHBeAg best KD of 1.7 log(mean max 1.2 log) following a single 4 mg/kg dose. In naïve pts, best qHBsAg KDof 1.9 log (mean max 1.1 log) in HBeAg-pos and 0.7 log (mean max 0.2 log) in HBeAg-negwere observed. qHBcrAg showed a dose response in HBeAg-neg with best KD at 1mg/kg of 0.18 log (mean max 0.15 log) and 1.1 log (mean max 0.9 log) with 4mg/kg. HBeAg-pos showed best KD of 1.1 log (mean max 0.92 log). The qHBsAg doseresponse was less deep in chronic ETV pts with bestobserved reduction of 0.3 log (mean max 0.2 log) observed at 1 mg/kg vs 0.5 log(mean max 0.4 log) at 4 mg/kg in HBeAg-neg. Best qHBsAg KD in chronic ETVtreated HBeAg-pos was 0.7 log (mean max 0.3 log). Divided doses at 4 mg/kg didnot increase antigen KD. Duration of qHBsAg KD was typically 8 wks with 2distinct KD patterns of qHBsAg seen: an immediate, direct ARC antiviral effect(~70% of pts) and a delayed response several weeks after treatment (~30% ofpts).
结果：ARC-520治疗表现出良好的耐受性，23%的用药者报告了轻微的或中度的不良反应，没有被评估为严重的，剧烈的，与用药相关的或导致病患退出试验的不良反应。乙肝DNA定量值低于全体服用恩替卡韦病患在参与研究时的初始值。初治患者的病毒DNA在接受ARC-520和恩替卡韦联合治疗后最高降低4.3log（平均2.2log）。（注3：1个log就是10的1次幂，因此最高降低4.3log就是说讲了10的4.3次幂。有网友说，降低1个log，就表示DNA降低了90%，如果是4个log，就是降低了99.99%，如果我没理解错的话）在单次按每公斤体重4毫克的给药条件下，ARC-520降低病毒抗原，e抗原最高降低1.7log，平均最大值为1.2log。在初治患者中，e抗原阳性病患的表抗最高降低1.9log，最大均值是1.1log；在e抗原阴性的病患中，表抗最高降低0.7log，最大均值0.2log。乙肝核相关抗原定量表明在e抗原阴性且按每公斤体重1毫克给药的病患中，乙肝核相关抗原最高降低0.18log，平均最大值0.15log；而在e抗原阴性按每公斤体重4毫克给药的病患中，乙肝核相关抗原最高降低1.1log，平均最大值为0.9log。而e抗原阳性的病患（注4：前面方法部分说了，这部分病患也是按每公斤体重4毫克给药）的乙肝核相关抗原最高降低1.1log，平均最大值0.92log。对乙肝表面抗原定量评估给药反应则表现一般，对于服用恩替卡韦的e抗原阴性的按每公斤体重1毫克给药的病患最高降低表抗0.3log，平均最大值0.2log，对于按每公斤体重4毫克给药的服用恩替卡韦且e抗原阴性的病患，表抗最高降低0.5log，平均最大值0.4log。而对于e抗原阳性服用恩替卡韦的病患，表抗最高降低0.7log，平均最高值0.3log。按每公斤体重4毫克标准分开给药不会增加相关抗原的降低。（注5：最后一句专业性强，不太好懂，但应该是解释前一句分开给药和一次给药没差异的，大体意思是在两种不同的给药模式下，同样都有70%的病患表现出即时的抗病毒疗效，而30%的病患表现出延时的抗病毒疗效）
Conclusions: 1) These findings areconsistent with more cccDNA-driven antigen production in HBeAg-pos. 2) ARC waswell tolerated 3) ARC effectively inhibited cccDNA-derived mRNA with protein KDup to 1.9 logs (99%) observed 4) These variations in viral protein KD are consistentwith ARC data in chimps and previously reported chronic ETV reductions in pts forcccDNA 5) Chronic ARC studies aimed at producing HBsAg seroclearance areunderway.
结论：1）这些发现与更多的自共价闭合环状DNA驱动的抗原产品在e抗原阳性病患中的疗效一致。（注6：这里的more...production不太好翻译，感觉很不通顺，可能是我理解不当）2）ARC-520具有良好的耐受性。3）ARC-520能有效地抑制衍生自共价闭合环状DNA的信使RNA，表现为其蛋白质最高降低1.9log（99%）。4）对于变异病毒蛋白质的降低与ARC-520以黑猩猩为试验对象和先前报告的服用恩替卡韦来对抗衍生自共价闭合环状DNA的结果相一致。（注7：自己解读吧）5）长期的意在实现表抗血清清除的ARC-520研究已经到来。