For research use only.
CAS No. 901119-35-5
Fostamatinib (R788), a prodrug of the active metabolite R406, is a Syk inhibitor with IC50 of 41 nM, strongly inhibits Syk but not Lyn, 5-fold less potent to Flt3. Phase 3.
Selleck's Fostamatinib (R788) has been cited by 26 publications
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|Description||Fostamatinib (R788), a prodrug of the active metabolite R406, is a Syk inhibitor with IC50 of 41 nM, strongly inhibits Syk but not Lyn, 5-fold less potent to Flt3. Phase 3.|
|Features||Converted into its active metabolite R406 in vivo.|
R788 is a prodrug of the spleen tyrosine kinase (Syk) inhibitor R406. R788 is a competitive inhibitor for ATP binding with a Ki of 30 nM. R788 dose-dependently inhibits anti-IgE-mediated CHMC degranulation with an EC50 of 56 nM. R788 also inhibits the anti-IgE-induced production and release of LTC4 and cytokines and chemokines, including TNFα, IL-8, and GM-CSF. Inhibition of Syk by R788 results in inhibition of all phosphorylation events downstream of Syk signaling. Next to FcϵRI signaling in CHMC, R788 most potently inhibits the signaling of IL-4 and IL-2 receptors. R788 specifically inhibits FcγR signaling in human mast cells, macrophages, and neutrophils. R788 can inhibit local inflammatory injury mediated by immune complexes.  R788 induces apoptosis of the majority of examined DLBCL cell lines. In R788-sensitive DLBCL cell lines, R788 specifically inhibits both tonic- and ligand-induced BCR signaling (autophosphorylation of SYK525/526 and SYK-dependent phosphorylation of the B-cell linker protein [BLNK]). 
|In vivo||Oral administration of R788 to mice reduces immune complex-mediated inflammation in a reverse-passive Arthus reaction and two antibody-induced arthritis models.  In another study, R788 effectively inhibits BCR signaling in vivo, resulting in reduced proliferation and survival of the malignant B cells and significantly prolongs survival of the treated animals.  R788 demonstrates a significant reduction in major inflammatory mediators such as TNFalpha, IL-1, IL-6 and IL-18, leading to reduced inflammation and bone degradation in models of rheumatoid arthritis. |
Fluorescence polarization kinase assay and Ki determination:The fluorescence polarization reactions are performed. For Ki determination, duplicate 200-μL reactions are set up at eight different ATP concentrations from 200 μM (2-fold serial dilutions) in the presence of either DMSO or R788 at 125, 62.5, 31.25, 15.5, or 7.8 nM. At different time points, 20 μL of each reaction is removed and quenched to stop the reaction. For each concentration of R788, the rate of reaction at each concentration of ATP is determined and plotted against the ATP concentration to determine the apparent Km and Vmax (maximal rate). Finally the apparent Km (or apparent Ki/Vmax) is plotted against the inhibitor concentration to determine the Ki.
|In vitro||DMSO||116 mg/mL (199.84 mM)|
|In vivo||Add solvents to the product individually and in order(Data is from Selleck tests instead of citations):
4% DMSO+30% PEG 300+ddH2O
For best results, use promptly after mixing.
* Please note that Selleck tests the solubility of all compounds in-house, and the actual solubility may differ slightly from published values. This is normal and is due to slight batch-to-batch variations.
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Clinical Trial Information
|NCT Number||Recruitment||interventions||Conditions||Sponsor/Collaborators||Start Date||Phases|
|NCT04543279||Recruiting||Drug: Fostamatinib|Drug: Ruxolitinib||Myelofibrosis||Washington University School of Medicine|Rigel Pharmaceuticals||May 3 2021||Phase 2|
|NCT04904276||Recruiting||Drug: Fostamatinib||ITP|Immune Thrombocytopenia||Rigel Pharmaceuticals||May 18 2021||--|
|NCT02611063||Recruiting||Drug: fostamatinib||Hematological Malignancies||Stefanie Sarantopoulos MD PhD.|Duke University||January 2016||Phase 1|
|NCT01725230||Completed||Drug: Fostamatinib|Drug: Rosuvastatin|Drug: Simvastatin||Rheumatoid Arthritis||AstraZeneca||November 2012||Phase 1|
|NCT01608542||Completed||Drug: Fostamatinib 100mg|Drug: Fostamatinib 200mg||Healthy Japanese Volunteers||AstraZeneca||June 2012||Phase 1|
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What’s the difference between S2625 and S2206?
S2206 is more stable than S2625. The water solubility of S2206 is better than S2625. The absorption of S2206 is harder than S2625, so you need to test the suitable dosage if you use the product in animal assays. The potency of S2206 and S2625 is similar.