K777 is a potent, orally active and irreversible cysteine protease inhibitor. K777 is also a potent CYP3A4 inhibitor with an IC₅₀ of 60 nM and a selective CCR4 antagonist featuring the potent chemotaxis inhibition. K777 irreversibly inhibits Cruzain, the major cysteine protease of Trypansoma cruzi, and cathepsins B and L. K777 is a broad-spectrum antiviral by targeting cathepsin-mediated cell entry. K777 inhibits SARS-CoV and EBOV pseudovirus entry with IC₅₀ values of 0.68 nM and 0.87 nM, respectively^[1][2][3].

Cysteine protease^[1][2][3]
IC50: 60 nM (CYP3A4)^[3]
CCR4^[3]

K777 (K11777) can inhibit entry driven by other viral envelope proteins, HIV-based pseudotypes bearing spikes from coronaviruses (SARS-CoV, HCoV-229E, NL63, MERS-CoV) or glycoproteins from filoviruses (EBOV, SUDV, TAFV, RESTV, BEBOV and MARV) are examined. K777 inhibits SARS-CoV, HCoV-229E, NL63, MERS-CoV, EBOV, SUDV, TAFV, RESTV, BEBOV, MARV and Nipah pseudovirus entry with IC₅₀ values of 0.68 nM, 1.48 nM, 6.78 nM, 46.12 nM, 0.87 nM, 1.14 nM, 2.26 nM, 3.37 nM, 5.91 nM, 1.9 nM and 0.42 nM, respectively. In contrast, 100 nM K777 does not inhibit infection mediated by envelope glycoproteins from an alphavirus (CHIKV), a rhabdovirus (VSV), a flavivirus (HCV), the retroviruses MLV-A and XMRV or two arenaviruses, Lassa and Junin virus^[1].
Whether K777 displays antiviral activity in TMPRSS2 expressing cells are assessed. For this, the incubated target cells with Camostat, K777, or a combination of K777 and Camostat and then infected with pseudoviruses bearing 229E-S. K777 alone demonstrates up to ~ 70% inhibition of 229E-S-mediated transduction. Simultaneous treatment with Camostat and K777 increases inhibition to ~ 90%. Similar inhibition patterns are obtained using the human intestinal epithelial cell line Caco-2, which express endogenous TMPRSS2 and cathepsins^[1].
K777 inhibits both CCL17 binding and CCL17-induced chemotaxis in Hut78 cells (IC₅₀ of 57 and 8.9 nM, respectively). The K777-mediated inhibition of chemotaxis is potent even in the presence of a 10-fold higher concentration of CCL17. K777 induces CCR4 internalization, with a ∼50% reduction of cell surface CCR4. K777 does not inhibit CXCR4-induced chemotaxis or internalization and did not bring about Ca²⁺ mobilization by itself^[3].

上海金畔生物科技有限公司 has not independently confirmed the accuracy of these methods. They are for reference only.

K777 (K11777; 35-105 mg/kg; oral administration; twice a day; for 10 days; C57BL/6 IFN-γR-KO mice) treatment rescues mice from otherwise lethal infections^[4] .

上海金畔生物科技有限公司 has not independently confirmed the accuracy of these methods. They are for reference only.

574.73

C₃₂H₃₈N₄O₄S

233277-99-1

Room temperature in continental US; may vary elsewhere.

Powder	-20°C	3 years
In solvent	-80°C	6 months
	-20°C	1 month

In Vitro: 

DMSO : 100 mg/mL (173.99 mM; Need ultrasonic)

*

请根据产品在不同溶剂中的溶解度选择合适的溶剂配制储备液；一旦配成溶液，请分装保存，避免反复冻融造成的产品失效。
储备液的保存方式和期限：-80°C, 6 months; -20°C, 1 month。-80°C 储存时，请在 6 个月内使用，-20°C 储存时，请在 1 个月内使用。

In Vivo:

请根据您的实验动物和给药方式选择适当的溶解方案。以下溶解方案都请先按照 In Vitro 方式配制澄清的储备液，再依次添加助溶剂：

——为保证实验结果的可靠性，澄清的储备液可以根据储存条件，适当保存；体内实验的工作液，建议您现用现配，当天使用； 以下溶剂前显示的百
分比是指该溶剂在您配制终溶液中的体积占比；如在配制过程中出现沉淀、析出现象，可以通过加热和/或超声的方式助溶

• 1.

  请依序添加每种溶剂： 10% DMSO    40% PEG300    5% Tween-80    45% saline

  Solubility: ≥ 2.5 mg/mL (4.35 mM); Clear solution

  此方案可获得 ≥ 2.5 mg/mL (4.35 mM，饱和度未知) 的澄清溶液。

  以 1 mL 工作液为例，取 100 μL 25.0 mg/mL 的澄清 DMSO 储备液加到 400 μL PEG300 中，混合均匀；向上述体系中加入50 μL Tween-80，混合均匀；然后继续加入 450 μL生理盐水定容至 1 mL。

  将 0.9 g 氯化钠，完全溶解于 100 mL ddH₂O 中，得到澄清透明的生理盐水溶液

• 2.

  请依序添加每种溶剂： 10% DMSO    90% (20% SBE-β-CD in saline)

  Solubility: ≥ 2.5 mg/mL (4.35 mM); Clear solution

  此方案可获得 ≥ 2.5 mg/mL (4.35 mM，饱和度未知) 的澄清溶液。

  以 1 mL 工作液为例，取 100 μL 25.0 mg/mL 的澄清 DMSO 储备液加到 900 μL 20% 的 SBE-β-CD 生理盐水水溶液中，混合均匀。

  将 2 g 磺丁基醚 β-环糊精加入 5 mL 生理盐水中，再用生理盐水定容至 10 mL，完全溶解，澄清透明
• 3.

  请依序添加每种溶剂： 10% DMSO    90% corn oil

  Solubility: ≥ 2.5 mg/mL (4.35 mM); Clear solution

  此方案可获得 ≥ 2.5 mg/mL (4.35 mM，饱和度未知) 的澄清溶液，此方案不适用于实验周期在半个月以上的实验。

  以 1 mL 工作液为例，取 100 μL 25.0 mg/mL 的澄清 DMSO 储备液加到 900 μL玉米油中，混合均匀。

• [1]. Zhou Y, et al. Protease inhibitors targeting coronavirus and filovirus entry. Antiviral Res. 2015 Apr;116:76-84.

  [2]. Jacobsen W, et al. In vitro evaluation of the disposition of A novel cysteine protease inhibitor. Drug Metab Dispos. 2000 Nov;28(11):1343-51.

  [3]. Sato T, et al. Internalization of CCR4 and inhibition of chemotaxis by K777, a potent and selective CCR4 antagonist. Pharmacology. 2013;91(5-6):305-13.

  [4]. Ndao M, et al. A cysteine protease inhibitor rescues mice from a lethal Cryptosporidium parvum infection. Antimicrob Agents Chemother. 2013 Dec;57(12):6063-73.