Table 1.

Case characteristics

	Age, years, sex	Race/ethnicity	Thrombotic risk factors	Year of ITP diagnosis	Time from diagnosis to start of fostamatinib, months	Previous ITP treatmentsa	Baseline platelets,b ×103/µL
Case 1	63, male	Non-Hispanic white	HTN HLP T2DM DVT	2018	2	Dexamethasone	59
Case 2	79, male	Non-Hispanic white	AF CAD HTN HLP PVD T2DM	2010	>24	Prednisone Rituximab	36
Case 3	60, female	Hispanic	DVT Obesity	2015	>24	Prednisone Rituximab Eltrombopag Platelet transfusions Romiplostim	39
Case 4	90, male	Non-Hispanic white	AF CAD	2014	>24	Prednisone	17
Case 5	82, male	Non-Hispanic white	AF CAD Obesity Smoker	2018	7	Platelet transfusion IVIg Prednisone Rituximab Eltrombopag	57

AF, atrial fibrillation; CAD, coronary artery disease; DVT, deep vein thrombosis; HLP, hyperlipidemia; HTN, hypertension; ITP, immune thrombocytopenia; IVIg, intravenous immunoglobulin; PVD, peripheral vascular disease; T2DM, type 2 diabetes mellitus.

^aTreatments are referenced in order of prescribing, but patients may have been on 1 or more treatments on numerous occasions.

^bPlatelet count was obtained immediately before the start of fostamatinib treatment.