PO058 | IMMUNOMODULATORY EFFECTS OF FOSTAMATINIB IN A PATIENT WITH EVANS SYNDROME, TRIPLE-POSITIVE ANTIPHOSPHOLIPID ANTIBODIES AND RELATED COAGULATION ABNORMALITIES
Abstract
Background. Fostamatinib is a spleen tyrosine kinase (Syk) inhibitor approved for immune thrombocytopenia, with emerging evidence suggesting a potential role in autoantibody-mediated disorders beyond platelet destruction. The aim of this report is to evaluate the role of fostamatinib in a patient with Evans syndrome, persistent antiphospholipid antibody (aPL) positivity, and laboratory abnormalities in coagulation tests. Case Report. A 32-year-old man who, in 2011, following an infectious episode, presented with prolonged PT and aPTT associated with Coombs-positive hemolytic anemia. Further investigations showed triple positivity for aPL (lupus anticoagulant, high-titer anticardiolipin and anti-β2GPI antibodies), medium-titer ANA, low C4 with normal C3; infectious screening was negative and past medical history was unremarkable. Steroid therapy was initiated, leading to complete resolution of hemolytic anemia and normalization of hemolysis markers, and was discontinued after two months. PT initially normalized and then showed progressive prolongation from 2013 onward. Concomitantly, thrombocytopenia was observed (nadir 69,000/mmc), along with mild splenomegaly and hilar lymphadenopathy. Bone marrow biopsy showed trilineage hyperplasia and features of hemophagocytosis; PET was negative, with a mild reduction in the CD4/CD8 ratio and no evidence of monoclonal gammopathy. Platelet count subsequently recovered spontaneously and remained stable (>100,000/mmc) for more than 10 years, with progressive normalization of spleen size. aPL remained persistently positive in the absence of thrombotic events; primary prophylaxis with low-dose aspirin was initiated in 2015. Given the persistent prolongation of PT and aPTT, coagulation factor assays showed a concordant reduction of intrinsic pathway factors (VIII, IX, XI, XII), with normal FVII levels. No clinically relevant bleeding events occurred. In 2024, progressive thrombocytopenia recurred, together with the detection of medium-titer anti-prothrombin IgG antibodies. At a platelet nadir of 31,000/mmc, a short course of steroids and fostamatinib was initiated, resulting in platelet recovery; steroids were subsequently discontinued while fostamatinib was continued. Concomitantly, stable normalization of PT, negativization of anti-prothrombin antibodies, and normalization of coagulation factor levels were observed. The temporal trend of coagulation parameters in relation to treatment is shown in Figure 1. Conclusions. Fostamatinib is a spleen tyrosine kinase (Syk) inhibitor with immunomodulatory activity on autoantibody-mediated effector mechanisms. Its effect is predominantly functional rather than serological, as it modulates downstream signaling without directly eliminating autoantibodies. In this context, the present case suggests a potential role for Syk inhibition in modulating aPL-related coagulation abnormalities.
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BibTeX
@article{bergonzi2026po058,
title = {{PO058 | IMMUNOMODULATORY EFFECTS OF FOSTAMATINIB IN A PATIENT WITH EVANS SYNDROME, TRIPLE-POSITIVE ANTIPHOSPHOLIPID ANTIBODIES AND RELATED COAGULATION ABNORMALITIES}},
author = {Sara Bergonzi},
journal = {Bleeding, Thrombosis and Vascular Biology},
year = {2026},
month = oct,
url = {https://www.btvb.org/btvb/article/view/874},
note = {CC BY-NC},
}
RIS
TY - JOUR
TI - PO058 | IMMUNOMODULATORY EFFECTS OF FOSTAMATINIB IN A PATIENT WITH EVANS SYNDROME, TRIPLE-POSITIVE ANTIPHOSPHOLIPID ANTIBODIES AND RELATED COAGULATION ABNORMALITIES
AU - Sara Bergonzi
PY - 2026
DA - 2026/10/26
JO - Bleeding, Thrombosis and Vascular Biology
UR - https://www.btvb.org/btvb/article/view/874
AB - Background. Fostamatinib is a spleen tyrosine kinase (Syk) inhibitor approved for immune thrombocytopenia, with emerging evidence suggesting a potential role in autoantibody-mediated disorders beyond platelet destruction. The aim of this report is to evaluate the role of fostamatinib in a patient with Evans syndrome, persistent antiphospholipid antibody (aPL) positivity, and laboratory abnormalities in coagulation tests. Case Report. A 32-year-old man who, in 2011, following an infectious episode, presented with prolonged PT and aPTT associated with Coombs-positive hemolytic anemia. Further investigations showed triple positivity for aPL (lupus anticoagulant, high-titer anticardiolipin and anti-β2GPI antibodies), medium-titer ANA, low C4 with normal C3; infectious screening was negative and past medical history was unremarkable. Steroid therapy was initiated, leading to complete resolution of hemolytic anemia and normalization of hemolysis markers, and was discontinued after two months. PT initially normalized and then showed progressive prolongation from 2013 onward. Concomitantly, thrombocytopenia was observed (nadir 69,000/mmc), along with mild splenomegaly and hilar lymphadenopathy. Bone marrow biopsy showed trilineage hyperplasia and features of hemophagocytosis; PET was negative, with a mild reduction in the CD4/CD8 ratio and no evidence of monoclonal gammopathy. Platelet count subsequently recovered spontaneously and remained stable (>100,000/mmc) for more than 10 years, with progressive normalization of spleen size. aPL remained persistently positive in the absence of thrombotic events; primary prophylaxis with low-dose aspirin was initiated in 2015. Given the persistent prolongation of PT and aPTT, coagulation factor assays showed a concordant reduction of intrinsic pathway factors (VIII, IX, XI, XII), with normal FVII levels. No clinically relevant bleeding events occurred. In 2024, progressive thrombocytopenia recurred, together with the detection of medium-titer anti-prothrombin IgG antibodies. At a platelet nadir of 31,000/mmc, a short course of steroids and fostamatinib was initiated, resulting in platelet recovery; steroids were subsequently discontinued while fostamatinib was continued. Concomitantly, stable normalization of PT, negativization of anti-prothrombin antibodies, and normalization of coagulation factor levels were observed. The temporal trend of coagulation parameters in relation to treatment is shown in Figure 1. Conclusions. Fostamatinib is a spleen tyrosine kinase (Syk) inhibitor with immunomodulatory activity on autoantibody-mediated effector mechanisms. Its effect is predominantly functional rather than serological, as it modulates downstream signaling without directly eliminating autoantibodies. In this context, the present case suggests a potential role for Syk inhibition in modulating aPL-related coagulation abnormalities.
SN - 2785-5309
ER -