AASLD1119 | ABI-4334，一种新型乙型肝炎病毒 核心抑制剂，加速

StephenW

1119 | ABI-4334，一种新型乙型肝炎病毒
核心抑制剂，加速衣壳
组装和抑制 CCCDNA 的形成
通过多种途径
Nuruddin Unchwaniwala1，卡罗琳 Pionek 2，丹尼尔 D.
Loeb2, William E. Delaney 1 和 Kathryn Kitrinos 3, (1)
Assembly Biosciences, Inc., (2)Mcardle 实验室
威斯康星大学麦迪逊分校癌症研究中心，
(3)临床病毒学，Assembly Biosciences, Inc.
背景：核心抑制剂 (CIs) 是一个新的类别
具有改善治愈潜力的 HBV 抗病毒药物
慢性HBV感染患者的发病率。因为
HBV核心蛋白的多功能作用，CIs影响
HBV 复制周期中的多个步骤，包括 (1)
共价闭合环状 DNA (cccDNA) 的形成
来自传入的 HBV，（2）新衣壳的形成和
前基因组 RNA (pgRNA) 外壳化，以及 (3) 在-
cccDNA的细胞外扩增。我们假设
具有针对所有三种途径的活性的高效 CI
方法将最大限度地提高临床疗效。在这里，我们
表明一个新的 CI，ABI-4334 (4334)，在
通过两种途径对抗 cccDNA 形成的体外活性
方式并且还破坏包含的传入衣壳
双链线性 DNA (DL-DNA)。方法：抑制
cccDNA 形成通过感染初级
人肝细胞 (PHH)，用 4334 治疗 3
小时（细胞质衣壳 DNA 终点）或 4 天
（核 cccDNA 终点），并测量 HBV DNA
通过Southern印迹。对于传入的 DL-DNA 效应
4334，HepG2-NTCP 细胞被感染，用
4334 3 小时，然后对细胞进行核酸酶处理
裂解物和通过Southern印迹测量的HBV DNA。
4334 通过细胞内 am- 对 cccDNA 形成的影响
通过诱导 HepAD38 细胞评估增殖
并用膦甲酸使 DNA 合成停滞 4 天，
然后用 4334 治疗 3 天，然后用 Southern
印迹。 4334 的衣壳装配效应通过以下方法分析
岩心的速度沉降和天然凝胶分析
来自诱导和 4334 处理的 HepAD38 细胞的蛋白质。
结果：4334 个过早中断的传入衣壳
并阻止受感染的 PHH 中的 cccDNA 形成
EC 50 为 3.1 nM。此外，4334 中断收入
感染的 HepG2 中含有衣壳的 DL-DNA-
NTCP 细胞，尽管浓度高出 5-10 倍
与松弛环状 DNA (RC-DNA) 衣壳相比
中断（图）。在人类预测的血浆
C min , 4334 通过显着抑制 cccDNA 的形成
细胞内扩增。分析衣壳形成
证明 4334 加速衣壳组装，
但会阻止 pgRNA 包装并诱导微妙的结构
衣壳的自然变化改变了它们的天然凝胶分子
能力。结论：4334 是一个有活性的有效 CI
防止通过传入衣壳形成 cccDNA 和
细胞内扩增。在 HBV 的早期阶段
感染，4334 过早破坏 RC-DNA 和
DL-含有衣壳的DNA。 1a 期首次人体试验
计划在 2H-2022 对 4334 进行研究。
披露：
Nuruddin Unchwaniwala – 组装生物科学：
就业；装配生物科学：库存
股东;
William E. Delaney – 装配生物科学：库存
股东;装配生物科学：就业；
Kathryn Kitrinos – Assembly Biosciences, Inc：
就业；
以下人员没有什么可透露的：卡罗琳
皮奥内克
披露信息在发布时不可用
lication：丹尼尔·D·勒布

StephenW

1119 | ABI- 4334, A NOVEL HEPATITIS B VIRUS
CORE INHIBITOR, ACCELERATES CAPSID
ASSEMBLY AND INHIBITS CCCDNA FORMATION
VIA MULTIPLE PATHWAYS
Nuruddin Unchwaniwala1, Karolyn Pionek 2, Daniel D.
Loeb2, William E. Delaney 1 and Kathryn Kitrinos 3, (1)
Assembly Biosciences, Inc., (2)Mcardle Laboratory for
Cancer Research, University of Wisconsin- Madison,
(3)Clinical Virology, Assembly Biosciences, Inc.
Background: Core inhibitors (CIs) are a novel class
of HBV antivirals with the potential to improve cure
rates in patients with chronic HBV infection. Due to the
multi-functional role of HBV core protein, CIs impact
multiple steps in the HBV replication cycle including (1)
formation of covalently closed circular DNA (cccDNA)
from incoming HBV, (2) new capsid formation and
pre- genomic RNA (pgRNA) encapsidation, and (3) in-
tracellular amplification of cccDNA. We hypothesize
a high potency CI with activity against all three path-
ways will maximize clinical effectiveness. Here we
show that a novel CI, ABI- 4334 (4334), has potent in
vitro activity against cccDNA formation via both path-
ways and also disrupts incoming capsids containing
duplex linear DNA (DL- DNA). Methods: Inhibition of
cccDNA formation was tested by infecting primary
human hepatocytes (PHH), treating with 4334 for 3
hours (cytoplasmic capsid DNA endpoint) or 4 days
(nuclear cccDNA endpoint), and measuring HBV DNA
by Southern blot. For the incoming DL- DNA effect of
4334, HepG2- NTCP cells were infected, treated with
4334 for 3 hours followed by nuclease treatment of cell
lysates, and HBV DNA measured by Southern blot.
4334 effects on cccDNA formation via intracellular am-
plification were evaluated by inducing HepAD38 cells
and stalling DNA synthesis with foscarnet for 4 days,
then treating with 4334 for 3 days followed by Southern
blot. Capsid assembly effects of 4334 was analyzed by
velocity sedimentation and native gel analysis of core
protein from induced and 4334 treated HepAD38 cells.
Results: 4334 prematurely disrupted incoming capsids
and blocked cccDNA formation in infected PHHs with
an EC 50 of 3.1 nM. Additionally, 4334 disrupted incom-
ing DL- DNA containing capsids in infected HepG2-
NTCP cells, albeit at a 5-10x higher concentrations
compared to relaxed circular DNA (RC- DNA) capsid
disruption (Figure). At the human predicted plasma
C min , 4334 significantly inhibited cccDNA formation via
intracellular amplification. Analyzing capsid formation
demonstrated that 4334 accelerates capsid assembly,
but blocks pgRNA packaging and induces subtle struc-
tural changes in capsids that alter their native gel mo-
bility. Conclusion: 4334 is a potent CI with activities
against cccDNA formation via incoming capsids and
intracellular amplification. During early stages of HBV
infection, 4334 prematurely disrupts both RC- DNA and
DL- DNA containing capsids. A Phase 1a first-in-human
study with 4334 is planned for 2H-2022.
Disclosures:
Nuruddin Unchwaniwala – Assembly Biosciences:
Employment; Assembly Biosciences: Stock
Shareholder;
William E. Delaney – Assembly Biosciences: Stock
Shareholder; Assembly Biosciences: Employment;
Kathryn Kitrinos – Assembly Biosciences, Inc:
Employment;
The following people have nothing to disclose: Karolyn
Pionek
Disclosure information not available at the time of pub-
lication: Daniel D. Loeb