Ensifentrine (RPL-554) 以浓度依赖性方式抑制人单核细胞由脂多糖产生的 TNF-α 释放（IC50 为 0.52 μM）及其响应植物血凝素的增殖（IC50 为 0.46 μM）[1]。 Ensifentrine (10 μM) 可有效抑制灌注豚鼠的离体气管制剂由电场刺激引起的收缩。灌注结束后，收缩反应被抑制长达 12 小时，RPL-554 表现出较长的作用持续时间[1]。

恩西芬汀（RPL-554；10 mg/kg；口服剂量；一次）在卵清蛋白致敏的豚鼠中可显着减少抗原攻击后嗜酸性粒细胞的募集[1]。当有意识的豚鼠在抗原暴露前 1.5 小时吸入含有依芬汀（25% 微粉化乳糖）的干粉时，嗜酸性粒细胞向气道的募集会受到显着抑制[1]。在 5.5 小时的过程中，清醒的豚鼠暴露于含有 2.5% 依芬汀微粉化乳糖的干粉后，显示出对组胺诱导的支气管收缩和气管中血浆蛋白外渗的显着抑制作用[1]。

Animal/Disease Models: Male Dunkin Hartley guinea pigs (200-300 g) injected with ovalbumin[1].
Doses: 10 mg/kg
Route of Administration: Oral administration; once
Experimental Results: Dramatically inhibits eosinophil recruitment following antigen challenge in ovalbumin-sensitized guinea pigs.

[1]. The pharmacology of two novel long-acting phosphodiesterase 3/4 inhibitors, RPL554 [9,10-dimethoxy-2(2,4,6-trimethylphenylimino)-3-(n-carbamoyl-2-aminoethyl)-3,4,6,7-tetrahydro-2H-pyrimido[6,1-a]isoquinolin-4-one] and RPL565 [6,7-dihydro-2-(2,6-diisopropylphenoxy)-9,10-dimethoxy-4H-pyrimido[6,1-a]isoquinolin-4-one]. J Pharmacol Exp Ther. 2006 Aug;318(2):840-8.

[2]. Symptom Improvement Following Treatment with the Inhaled Dual Phosphodiesterase 3 and 4 Inhibitor Ensifentrine in Patients with Moderate to Severe COPD - A Detailed Analysis. Int J Chron Obstruct Pulmon Dis. 2020 Sep 16;15:2199-2206.

Ensifentrine is under investigation in clinical trial NCT04535986 (A Phase 3 Clinical Trial to Evaluate the Safety and Efficacy of Ensifentrine in Patients With COPD).
Ensifentrine is an inhaled inhibitor of the phosphodiesterase (PDE) types 3 (PDE3) and 4 (PDE4), with potential anti-inflammatory and bronchodilator activities. Upon administration, ensifentrine targets, binds to and inhibits PDE3 and PDE4, which leads to an increase of both intracellular levels of cyclic-3',5'-adenosine monophosphate (cAMP) and cAMP-mediated signaling. This may lead to bronchial smooth muscle relaxation and modulate inflammatory responses. PDE3 and PDE4, members of the PDE superfamily, hydrolyze cAMP and 3',5'-cyclic guanosine monophosphate (cGMP) to their inactive 5' monophosphates. PDE3 is the most expressed PDE isoenzyme in bronchial smooth muscle. PDE4 is expressed in immune cells including T-cells, monocytes, macrophages, neutrophils, dendritic cells and eosinophils. It plays an important role in inflammation, especially in inflammatory airway diseases.

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Mechanism of Action
Ensifentrine is a dual inhibitor of phosphodiesterase 3 (PDE3) and phosphodiesterase 4 (PDE4); it is also an activator of the cystic fibrosis transmembrane conductance regulator (CFTR). This drug has bronchodilatory and anti-inflammatory properties due to the dual inhibition; it also has mucous viscosity reduction and improved mucociliary clearance effects due to the CFTR activation. Ensifentrine is currently being investigated against COPD, cystic fibrosis, asthma, other respiratory diseases, and COVID-19.

C26H31N5O4

477.5554

477.237

1884461-72-6

(E/Z)-Ensifentrine;298680-25-8

9934746

Light yellow to green yellow solid powder

2.7

110

2

5

6

35

849

0

O=C1N(C([H])([H])C([H])([H])N([H])C(N([H])[H])=O)/C(/C([H])=C2C3=C([H])C(=C(C([H])=C3C([H])([H])C([H])([H])N21)OC([H])([H])[H])OC([H])([H])[H])=N/C1C(C([H])([H])[H])=C([H])C(C([H])([H])[H])=C([H])C=1C([H])([H])[H]

CSOBIBXVIYAXFM-BYNJWEBRSA-N

InChI=1S/C26H31N5O4/c1-15-10-16(2)24(17(3)11-15)29-23-14-20-19-13-22(35-5)21(34-4)12-18(19)6-8-30(20)26(33)31(23)9-7-28-25(27)32/h10-14H,6-9H2,1-5H3,(H3,27,28,32)/b29-23+

N-(2-{(2E)-9,10-dimethoxy-4-oxo-2-[(2,4,6- trimethylphenyl)imino]-6,7-dihydro-2H-pyrimido[6,1- a]isoquinolin-3(4H)-yl}ethyl)urea

Ensifentrine RPL-554 Ensifentrina RPL554 Ensifentrinum

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

DMSO : ~25 mg/mL (~52.35 mM)

配方 1 中的溶解度: ≥ 1.25 mg/mL (2.62 mM) (饱和度未知) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (这些助溶剂从左到右依次添加，逐一添加), 澄清溶液。
例如，若需制备1 mL的工作液，可将100 μL 12.5 mg/mL澄清的DMSO储备液加入到400 μL PEG300中，混匀；再向上述溶液中加入50 μL Tween-80，混匀；然后加入450 μL生理盐水定容至1 mL。
*生理盐水的制备：将 0.9 g 氯化钠溶解在 100 mL ddH₂O中，得到澄清溶液。

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配方 2 中的溶解度: 1.25 mg/mL (2.62 mM) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (这些助溶剂从左到右依次添加，逐一添加), 悬浊液; 超声助溶。
例如，若需制备1 mL的工作液，可将 100 μL 12.5 mg/mL澄清DMSO储备液加入900 μL 20% SBE-β-CD生理盐水溶液中，混匀。
*20% SBE-β-CD 生理盐水溶液的制备（4°C，1 周）：将 2 g SBE-β-CD 溶解于 10 mL 生理盐水中，得到澄清溶液。

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请根据您的实验动物和给药方式选择适当的溶解配方/方案：
1、请先配制澄清的储备液(如：用DMSO配置50 或 100 mg/mL母液(储备液));
2、取适量母液，按从左到右的顺序依次添加助溶剂，澄清后再加入下一助溶剂。以 下列配方为例说明 (注意此配方只用于说明，并不一定代表此产品 的实际溶解配方):
10% DMSO → 40% PEG300 → 5% Tween-80 → 45% ddH2O (或 saline);
假设最终工作液的体积为 1 mL, 浓度为5 mg/mL: 取 100 μL 50 mg/mL 的澄清 DMSO 储备液加到 400 μL PEG300 中，混合均匀/澄清；向上述体系中加入50 μL Tween-80，混合均匀/澄清；然后继续加入450 μL ddH2O (或 saline)定容至 1 mL；
3、溶剂前显示的百分比是指该溶剂在最终溶液/工作液中的体积所占比例;
4、 如产品在配制过程中出现沉淀/析出，可通过加热(≤50℃)或超声的方式助溶;
5、为保证最佳实验结果，工作液请现配现用！
6、如不确定怎么将母液配置成体内动物实验的工作液，请查看说明书或联系我们;
7、 以上所有助溶剂都可在 Invivochem.cn网站购买。