| Bioactivity | Darapladib is a potent inhibitor of lipoprotein-associated phospholipase A2 (Lp-PLA2) with IC50 of 0.25 nM. | ||||||||||||
| Target | IC50: 0.25 nM (Lp-PLA2) | ||||||||||||
| Invitro | Mechanistic studies using steady state and transient kinetics indicate Darapladib (SB-480848) to be a freely reversible, non-covalently bound, inhibitor of rhLp-PLA2 with a Ki of 110 pM and an off-rate of 27 min. Potent inhibition of the enzyme in whole human plasma is confirmed (IC50=5±2 nM). Furthermore, the presence of Darapladib during the copper catalysed oxidation of human LDL prevents the production of lyso-PtdCho (IC50=4±3 nM) and subsequent monocyte chemotaxis (IC50=4±1 nM)[1]. | ||||||||||||
| In Vivo | Additional in vivo studies with Darapladib indicated an oral bioavailability of 11±2% in the fed rat. The oral bioavailability of Darapladib is 28±4% in the dog. Furthermore excellent inhibition of Lp-PLA2 within the atherosclerotic plaque is achieved for Darapladib, with 95±1% inhibition observed 2 h after an oral dose of 30 mg/kg to the WHHL rabbit[1]. Darapladib, a specific inhibitor of lipoprotein-associated phospholipase A2 (lp-PLA2), on inflammation and atherosclerotic formation in the low density lipoprotein receptor (LDLR)-deficient mice. the activity of serum lp-PLA2 is inhibited by more than 60% in LDLR-deficient mice after oral administration of 50 mg/kg once daily of Darapladib for 6 weeks. Darapladib significantly inhibits serum lp-PLA2 activity in LDLR-deficient mice[2]. | ||||||||||||
| Name | Darapladib | ||||||||||||
| CAS | 356057-34-6 | ||||||||||||
| Formula | C36H38F4N4O2S | ||||||||||||
| Molar Mass | 666.77 | ||||||||||||
| Appearance | Solid | ||||||||||||
| Transport | Room temperature in continental US; may vary elsewhere. | ||||||||||||
| Storage |
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| Reference | [1]. Blackie JA, et al. The identification of clinical candidate SB-480848: a potent inhibitor of lipoprotein-associated phospholipase A2. Bioorg Med Chem Lett. 2003 Mar 24;13(6):1067-70. [2]. Hu MM, et al. The inhibition of lipoprotein-associated phospholipase A2 exerts beneficial effects against atherosclerosis inLDLR-deficient mice. Acta Pharmacol Sin. 2011 Oct;32(10):1253-1258. |