Ensifentrine (RPL-554) is an inhaled first-in-class dual inhibitor ofphosphodiesterase3 (PDE3)andPDE4withIC₅₀s of 0.4 nM and 1479 nM, respectively. Ensifentrine has bronchoprotective and anti-inflammatory activities. Ensifentrine can be used for chronic obstructive pulmonary disease (COPD) research^[1][2].

Ensifentrine (RPL-554) inhibits, in a concentration-dependent manner, lipopolysaccharide-induced TNF-α release from human monocytes (IC₅₀of 0.52 μM) and proliferation of human mononuclear cells to phytohemagglutinin (IC₅₀of 0.46 μM)^[1].
Electrical field stimulation-induced contraction of guinea pig superfused isolated tracheal preparations is significantly inhibited by Ensifentrine (10 μM). Contractile responses are suppressed for up to 12 h after termination of superfusion with RPL-554 demonstrating a long duration of action^[1].

Ensifentrine (RPL-554; 10 mg/kg; Oral administration; once) significantly inhibits eosinophil recruitment following antigen challenge in ovalbumin-sensitized guinea pigs^[1].
The inhalation of dry powder containing Ensifentrine by conscious guinea pigs (25% in micronized lactose) 1.5 h before antigen exposure significantly inhibits the recruitment of eosinophils to the airways^[1].
Exposure of conscious guinea pigs to inhalation of dry powder containing Ensifentrine (2.5%) in micronized lactose significantly inhibits histamine-induced plasma protein extravasation in the trachea and histamine-induced bronchoconstriction over a 5.5-h period^[1].

477.56

Solid

C₂₆H₃₁N₅O₄

1884461-72-6

Room temperature in continental US; may vary elsewhere.

DMSO : 25 mg/mL(52.35 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℃, 6 months; -20℃, 1 month。-80℃ 储存时，请在 6 个月内使用，-20℃ 储存时，请在 1 个月内使用。

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: ≥ 1.25 mg/mL (2.62 mM); Clear solution

  此方案可获得 ≥ 1.25 mg/mL (2.62 mM，饱和度未知) 的澄清溶液。

  以 1 mL 工作液为例，取 100 μL 12.5 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-CDin saline)

  Solubility: 1.25 mg/mL (2.62 mM); Suspended solution; Need ultrasonic

  此方案可获得 1.25 mg/mL (2.62 mM) 的均匀悬浊液，悬浊液可用于口服和腹腔注射。

  以 1 mL 工作液为例，取 100 μL 12.5 mg/mL 的澄清 DMSO 储备液加到 900 μL20% 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