Fostamatinib sodium

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MedKoo CAT#: 200393

CAS#: 1025687-58-4 (sodium)

Description: Fostamatinib, also known as R 788 and R-935788, is an orally active, potent and selective Syk kinase inhibitor with potential anti-inflammatory and immunomodulating activities. Fostamatinib is also a pro-drug of R-406. Fostamatinib inhibits Syk kinase-mediated IgG Fc gamma receptor signaling, resulting in inhibition of the activation of mast cells, macrophages, and B-cells and related inflammatory responses and tissue damage.

Chemical Structure

Fostamatinib sodium
CAS# 1025687-58-4 (sodium)

Theoretical Analysis

MedKoo Cat#: 200393
Name: Fostamatinib sodium
CAS#: 1025687-58-4 (sodium)
Chemical Formula: C23H24FN6Na2O9P
Exact Mass:
Molecular Weight: 624.42
Elemental Analysis: C, 44.24; H, 3.87; F, 3.04; N, 13.46; Na, 7.36; O, 23.06; P, 4.96

Size Price Shipping out time Quantity
25mg USD 150 Same day
50mg USD 250 Same day
100mg USD 450 Same day
200mg USD 750 Same day
500mg USD 1350 Same day
1g USD 2250 Same day
2g USD 3450 Same day
5g USD 4950 2 weeks
10g USD 7750 2 weeks
Inquire bulk and customized quantity

Pricing updated 2021-02-27. Prices are subject to change without notice.

Fostamatinib sodium, purity > 98%, is in stock.

Related CAS #: 1025687-58-4 (sodium)   901119-35-5 (free acid)   914295-16-2 (sodium hydrate)  

Synonym: R935788; R-935788; R 935788; R788; R 788; R-788 sodium. R935788 sodium. Fostamatinib sodium, Fostamatinib disodium hexahydrate; prodrug of R-406.

IUPAC/Chemical Name: sodium (6-((5-fluoro-2-((3,4,5-trimethoxyphenyl)amino)pyrimidin-4-yl)amino)-2,2-dimethyl-3-oxo-2H-pyrido[3,2-b][1,4]oxazin-4(3H)-yl)methyl phosphate


InChi Code: InChI=1S/C23H26FN6O9P.2Na/c1-23(2)21(31)30(11-38-40(32,33)34)20-14(39-23)6-7-17(28-20)27-19-13(24)10-25-22(29-19)26-12-8-15(35-3)18(37-5)16(9-12)36-4;;/h6-10H,11H2,1-5H3,(H2,32,33,34)(H2,25,26,27,28,29);;/q;2*+1/p-2

SMILES Code: O=P([O-])([O-])OCN1C2=NC(NC3=NC(NC4=CC(OC)=C(OC)C(OC)=C4)=NC=C3F)=CC=C2OC(C)(C)C1=O.[Na+].[Na+]

white solid powder

>98% (or refer to the Certificate of Analysis)

Shipping Condition:
Shipped under ambient temperature as non-hazardous chemical. This product is stable enough for a few weeks during ordinary shipping and time spent in Customs.

Storage Condition:
Dry, dark and at 0 - 4 C for short term (days to weeks) or -20 C for long term (months to years).

Soluble in DMSO, not in water

Shelf Life:
>2 years if stored properly

Drug Formulation:
This drug may be formulated in DMSO

Stock Solution Storage:
0 - 4 C for short term (days to weeks), or -20 C for long term (months).

HS Tariff Code:

Preparing Stock Solutions

The following data is based on the product molecular weight 624.42 Batch specific molecular weights may vary from batch to batch due to the degree of hydration, which will affect the solvent volumes required to prepare stock solutions.

Select a batch to recalculate based on the batch molecular weight:
Concentration / Solvent Volume / Mass 1 mg 5 mg 10 mg
1 mM 1.15 mL 5.76 mL 11.51 mL
5 mM 0.23 mL 1.15 mL 2.3 mL
10 mM 0.12 mL 0.58 mL 1.15 mL
50 mM 0.02 mL 0.12 mL 0.23 mL

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1: McBride A, Nayak P, Kreychman Y, Todd L, Duliege AM, Mehta AR. Fostamatinib disodium hexahydrate: a novel treatment for adult immune thrombocytopenia. Am J Manag Care. 2019 Nov;25(19 Suppl):S347-S358. PubMed PMID: 31809006.

2: LiverTox: Clinical and Research Information on Drug-Induced Liver Injury [Internet]. Bethesda (MD): National Institute of Diabetes and Digestive and Kidney Diseases; 2012-. Available from PubMed PMID: 31643662.

3: Kang Y, Jiang X, Qin D, Wang L, Yang J, Wu A, Huang F, Ye Y, Wu J. Efficacy and Safety of Multiple Dosages of Fostamatinib in Adult Patients With Rheumatoid Arthritis: A Systematic Review and Meta-Analysis. Front Pharmacol. 2019 Aug 14;10:897. doi: 10.3389/fphar.2019.00897. eCollection 2019. PubMed PMID: 31474860; PubMed Central PMCID: PMC6702340.

4: Hussar DA, Kludjian GA. Prucalopride succinate, Fostamatinib disodium hexahydrate, Avatrombopag maleate, and Lusutrombopag. J Am Pharm Assoc (2003). 2019 Jul - Aug;59(4):601-604. doi: 10.1016/j.japh.2019.05.013. PubMed PMID: 31296323.

5: Moore DC, Gebru T, Muslimani A. Fostamatinib for the treatment of immune thrombocytopenia in adults. Am J Health Syst Pharm. 2019 May 17;76(11):789-794. doi: 10.1093/ajhp/zxz052. PubMed PMID: 30951590.

6: Fostamatinib (Tavalisse) for ITP. Med Lett Drugs Ther. 2019 Feb 25;61(1566):28-30. PubMed PMID: 30845102.

7: Connell NT, Berliner N. Fostamatinib for the treatment of chronic immune thrombocytopenia. Blood. 2019 May 9;133(19):2027-2030. doi: 10.1182/blood-2018-11-852491. Epub 2019 Feb 25. Review. PubMed PMID: 30803989.

8: Bussel JB, Arnold DM, Boxer MA, Cooper N, Mayer J, Zayed H, Tong S, Duliege AM. Long-term fostamatinib treatment of adults with immune thrombocytopenia during the phase 3 clinical trial program. Am J Hematol. 2019 May;94(5):546-553. doi: 10.1002/ajh.25444. Epub 2019 Mar 13. PubMed PMID: 30784097; PubMed Central PMCID: PMC6594140.

9: McKeage K, Lyseng-Williamson KA. Fostamatinib in chronic immune thrombocytopenia: a profile of its use in the USA. Drugs Ther Perspect. 2018;34(10):451-456. doi: 10.1007/s40267-018-0551-x. Epub 2018 Aug 29. Erratum in: Drugs Ther Perspect. 2018;34(12):594. PubMed PMID: 30459507; PubMed Central PMCID: PMC6223701.

10: Markham A. Fostamatinib: First Global Approval. Drugs. 2018 Jun;78(9):959-963. doi: 10.1007/s40265-018-0927-1. Review. PubMed PMID: 29869203.

11: Bussel J, Arnold DM, Grossbard E, Mayer J, Treliński J, Homenda W, Hellmann A, Windyga J, Sivcheva L, Khalafallah AA, Zaja F, Cooper N, Markovtsov V, Zayed H, Duliege AM. Fostamatinib for the treatment of adult persistent and chronic immune thrombocytopenia: Results of two phase 3, randomized, placebo-controlled trials. Am J Hematol. 2018 Jul;93(7):921-930. doi: 10.1002/ajh.25125. Epub 2018 May 15. PubMed PMID: 29696684; PubMed Central PMCID: PMC6055608.

12: McKeage K, Lyseng-Williamson KA. Correction to: Fostamatinib in chronic immune thrombocytopenia: a profile of its use in the USA. Drugs Ther Perspect. 2018;34(12):594. doi: 10.1007/s40267-018-0575-2. Epub 2018 Nov 16. PubMed PMID: 31186610; PubMed Central PMCID: PMC6267526.

13: Newland A, Lee EJ, McDonald V, Bussel JB. Fostamatinib for persistent/chronic adult immune thrombocytopenia. Immunotherapy. 2018 Jan;10(1):9-25. doi: 10.2217/imt-2017-0097. Epub 2017 Oct 2. Review. PubMed PMID: 28967793.

14: Flanagan T, Martin P, Gillen M, Mathews D, Lisbon E, Kruusmägi M. Effects of ranitidine (antacid), food, and formulation on the pharmacokinetics of fostamatinib: results from five phase I clinical studies. Eur J Clin Pharmacol. 2017 Feb;73(2):185-195. doi: 10.1007/s00228-016-2156-4. Epub 2016 Nov 17. PubMed PMID: 27858108.

15: Martin P, Gillen M, Millson D, Oliver S, Brealey C, Surry D, Sweeny D, Lau D, Leese P. Effects of Fostamatinib on the Pharmacokinetics of the CYP2C8 Substrate Pioglitazone: Results From In Vitro and Phase 1 Clinical Studies. Clin Pharmacol Drug Dev. 2016 May;5(3):170-9. doi: 10.1002/cpdd.243. Epub 2016 Mar 23. PubMed PMID: 27163495.

16: Kunwar S, Devkota AR, Ghimire DK. Fostamatinib, an oral spleen tyrosine kinase inhibitor, in the treatment of rheumatoid arthritis: a meta-analysis of randomized controlled trials. Rheumatol Int. 2016 Aug;36(8):1077-87. doi: 10.1007/s00296-016-3482-7. Epub 2016 Apr 25. PubMed PMID: 27113955.

17: Martin P, Gillen M, Ritter J, Mathews D, Brealey C, Surry D, Oliver S, Holmes V, Severin P, Elsby R. Effects of Fostamatinib on the Pharmacokinetics of Oral Contraceptive, Warfarin, and the Statins Rosuvastatin and Simvastatin: Results From Phase I Clinical Studies. Drugs R D. 2016 Mar;16(1):93-107. doi: 10.1007/s40268-015-0120-x. PubMed PMID: 26748647; PubMed Central PMCID: PMC4767723.

18: Martin P, Gillen M, Millson D, Oliver S, Brealey C, Grossbard EB, Baluom M, Lau D, Sweeny D, Mant T, Craven K. Effects of CYP3A4 Inhibitors Ketoconazole and Verapamil and the CYP3A4 Inducer Rifampicin on the Pharmacokinetic Parameters of Fostamatinib: Results from In Vitro and Phase I Clinical Studies. Drugs R D. 2016 Mar;16(1):81-92. doi: 10.1007/s40268-015-0118-4. PubMed PMID: 26739683; PubMed Central PMCID: PMC4767720.

19: Flinn IW, Bartlett NL, Blum KA, Ardeshna KM, LaCasce AS, Flowers CR, Shustov AR, Thress KS, Mitchell P, Zheng F, Skolnik JM, Friedberg JW. A phase II trial to evaluate the efficacy of fostamatinib in patients with relapsed or refractory diffuse large B-cell lymphoma (DLBCL). Eur J Cancer. 2016 Feb;54:11-17. doi: 10.1016/j.ejca.2015.10.005. Epub 2015 Dec 18. PubMed PMID: 26707592.

20: Martin P, Oliver S, Gillen M, Marbury T, Millson D. Pharmacokinetic Properties of Fostamatinib in Patients With Renal or Hepatic Impairment: Results From 2 Phase I Clinical Studies. Clin Ther. 2015 Dec 1;37(12):2823-36. doi: 10.1016/j.clinthera.2015.09.016. Epub 2015 Oct 27. PubMed PMID: 26519231.

Additional Information

Fostamatinib is an experimental drug candidate for the treatment of a variety of diseases. It is in Phase III clinical trials for rheumatoid arthritis and Phase II trials for autoimmune thrombocytopenia and lymphoma.  The oral drug is used as its disodium salt and it is a prodrug of the active compound tamatinib (R-406), which is an inhibitor of the enzyme spleen tyrosine kinase (Syk) (source: