Fondaparinux

Fondaparinux

Clinical data
Trade names	Arixtra
AHFS/Drugs.com	Monograph
License data	EU EMA: Arixtra US FDA: Fondaparinux
Routes of administration	subcutaneous
ATC code	B01AX05 (WHO)
Legal status
Legal status	UK: POM (Prescription only) US: ℞-only
Pharmacokinetic data
Bioavailability	N/A
Protein binding	94%
Metabolism	renally excreted unchanged
Biological half-life	17-21 hours
Identifiers
CAS Number	104993-28-4 N decasodium salt: 114870-03-0 N
PubChem CID	636380
DrugBank	DB00569 Y
ChemSpider	552174 Y
UNII	J177FOW5JL decasodium salt: X0Q6N9USOZ N
ChEMBL	CHEMBL1201202 N
ECHA InfoCard	100.212.026
Chemical and physical data
Formula	C31H43N3Na10O49S8
Molar mass	1726.77 g/mol
3D model (Jmol)	Interactive image
SMILES [Na+].[Na+].[Na+].[Na+].[Na+].[Na+].[Na+].[Na+].[Na+].[Na+].[O-]S(=O)(=O)N[C@@H]5[C@@H](O)[C@H](O)[C@@H](COS([O-])(=O)=O)O[C@@H]5O[C@H]1[C@H](O)[C@@H](O)[C@@H](O[C@@H]1C([O-])=O)O[C@@H]4[C@@H](COS([O-])(=O)=O)O[C@H](O[C@H]3[C@H](O)[C@@H](OS([O-])(=O)=O)[C@H](O[C@H]2[C@H](O)[C@@H](NS([O-])(=O)=O)[C@@H](OC)O[C@@H]2COS([O-])(=O)=O)O[C@H]3C([O-])=O)[C@H](NS([O-])(=O)=O)[C@H]4OS([O-])(=O)=O
InChI InChI=1S/C31H53N3O49S8.10Na/c1-69-27-9(33-85(48,49)50)13(37)17(6(74-27)3-71-88(57,58)59)76-31-22(83-91(66,67)68)16(40)21(24(81-31)26(43)44)79-29-10(34-86(51,52)53)19(82-90(63,64)65)18(7(75-29)4-72-89(60,61)62)77-30-15(39)14(38)20(23(80-30)25(41)42)78-28-8(32-84(45,46)47)12(36)11(35)5(73-28)2-70-87(54,55)56;;;;;;;;;;/h5-24,27-40H,2-4H2,1H3,(H,41,42)(H,43,44)(H,45,46,47)(H,48,49,50)(H,51,52,53)(H,54,55,56)(H,57,58,59)(H,60,61,62)(H,63,64,65)(H,66,67,68);;;;;;;;;;/q;10*+1/p-10/t5-,6-,7-,8-,9-,10-,11-,12-,13-,14-,15-,16+,17-,18-,19-,20+,21+,22-,23+,24-,27+,28-,29-,30-,31-;;;;;;;;;;/m1........../s1 Y Key:XEKSTYNIJLDDAZ-JASSWCPGSA-D Y
NY (what is this?)

Fondaparinux (trade name Arixtra) is an anticoagulant medication chemically related to low molecular weight heparins. It is marketed by GlaxoSmithKline. A generic version developed by Alchemia is marketed within the US by Dr. Reddy's Laboratories.

Fondaparinux is a synthetic pentasaccharide factor Xa inhibitor. Apart from the O-methyl group at the reducing end of the molecule, the identity and sequence of the five monomeric sugar units contained in fondaparinux is identical to a sequence of five monomeric sugar units that can be isolated after either chemical or enzymatic cleavage of the polymeric glycosaminoglycans heparin and heparin sulfate (HS). Within heparin and heparin sulfate this monomeric sequence is thought to form the high-affinity binding site for the anti-coagulant factor antithrombin III (ATIII). Binding of heparin/HS to ATIII has been shown to increase the anti-coagulant activity of antithrombin III 1000 fold. In contrast to heparin, fondaparinux does not inhibit thrombin.

Fondaparinux is given subcutaneously daily. Clinically, it is used for the prevention of deep vein thrombosis in patients who have had orthopedic surgery as well as for the treatment of deep vein thrombosis and pulmonary embolism.

One potential advantage of fondaparinux over LMWH or unfractionated heparin is that the risk for heparin-induced thrombocytopenia (HIT) is substantially lower. Furthermore, there have been case reports of fondaparinux being used to anti-coagulate patients with established HIT as it has no affinity to PF-4. However, its renal excretion precludes its use in patients with renal dysfunction.

Unlike direct factor Xa inhibitors, it mediates its effects indirectly through antithrombin III, but unlike heparin, it is selective for factor Xa.