PPACK 

PPACK nanoparticles completely inhibit thrombin-induced cleavage of the PAR-1 receptor on human aortic endothelial cells, as well as tissue factor expression on the surface of THP-1 monocytes^[1].
PPACK nanoparticles inhibit thrombin-induced NF-κB activation in human aortic endothelial cells and THP-1 monocytes^[1].
PPACK (5-fold molar excess; room temperature; 1 h) inactivates the amidolytic activity of human α-thrombin after 1 h of incubation at room temperature, generating PPACK-thrombin that does not interfere with the enzymatic function of unmodified α-thrombin^[4].
PPACK (200 μM, 100 μM, 10 μM) exerts anticoagulant effects, and exhibits stronger anticoagulant activity on a molar basis than the factor Xa inhibitor GGACK (HY-137495) used alone at the same concentrations^[5].

MedChemExpress (MCE) has not independently confirmed the accuracy of these methods. They are for reference only.

Intravenous administration of PPACK nanoparticles (intravenous injection; 3 times per week; for 4 consecutive weeks) to high-fat diet-fed ApoE knockout mice reduces vascular procoagulant activity, restores endothelial barrier integrity, delays plaque progression, and attenuates inflammatory signaling in atherosclerotic plaques, without inducing systemic anticoagulation or altering serum cholesterol levels^[1].
PPACK (62.5 μg; i.p.; every 2 days; 8 to 18 days post-immunization) significantly attenuates airway eosinophilia, goblet cell hyperplasia and airway hyperresponsiveness in a mouse model of asthma^[3].

MedChemExpress (MCE) has not independently confirmed the accuracy of these methods. They are for reference only.

450.96

C₂₁H₃₁ClN₆O₃

71142-71-7

{d-Phe}-Pro-{Arg-Chloromethylketone}

{d-Phe}-P-{Arg-Chloromethylketone}

Room temperature in continental US; may vary elsewhere.

Please store the product under the recommended conditions in the Certificate of Analysis.

• [1]. Palekar RU, et al. Inhibition of Thrombin With PPACK-Nanoparticles Restores Disrupted Endothelial Barriers and Attenuates Thrombotic Risk in Experimental Atherosclerosis. Arterioscler Thromb Vasc Biol. 2016;36(3):446-455.  [Content Brief]

  [2]. Wu Y, et al. The inhibitory effect of antiplatelet drugs on spontaneous platelet aggregation on glass surfaces: an analysis based on microscopic three-dimensional topography. J Thromb Thrombolysis. Published online September 9, 2025.  [Content Brief]

  [3]. Lan F, et al. GZMK-expressing CD8⁺ T cells promote recurrent airway inflammatory diseases. Nature. 2025;638(8050):490-498.  [Content Brief]

  [4]. Schmaier AH, et al. PPACK-thrombin is a noncompetitive inhibitor of alpha-thrombin binding to human platelets. Thromb Res. 1992;67(5):479-489.  [Content Brief]

  [5]. Lyon ME, et al. Evaluation of the thrombin inhibitor D-phenylalanyl-L-prolyl-L-arginine chloromethylketone (PPACK) with the factor Xa inhibitor 1,5-dansyl-L-glutamyl-L-glycyl-L-arginine chloromethylketone (GGACK) as anticoagulants for critical care clinical chemistry specimens. Clin Chim Acta. 1999 Feb;280(1-2):91-9.  [Content Brief]