Fostamatinib for treating refractory chronic immune thrombocytopenia (ITP)

Fostamatinib for treating refractory chronic immune thrombocytopenia (ITP)

• first line of therapy for ITP includes corticosteroids, sometimes in conjunction with IVIg or anti-Rh(D). While these are effective therapies, none reliably induce durable remission (1)
  • second line therapy for ITP may include Rituximab, splenectomy or thrombopoietin receptor agonists (TRAs)
• fostamitinib
  • is the first spleen tyrosine kinase (Syk) inhibitor approved for the treatment of chronic immune thrombocytopenia (ITP) in adult patients who have had an insufficient response to previous treatment (3)
  • by inhibiting Syk activation in macrophages, fostamatinib blocks autoantibody-mediated platelet phagocytosis

NICE state (3):

• fostamatinib is recommended as an option for treating refractory chronic immune thrombocytopenia (ITP) in adults, only if:
  • they have previously had a thrombopoietin receptor agonist (TPO-RA), or a TPO-RA is unsuitable
  • the company provides fostamatinib according to the commercial arrangement
• the NICE committee note that:
  • treatment options for refractory chronic ITP include TPO-RAs, which are mostly followed by rituximab or mycophenolate
  • clinical evidence shows that fostamatinib is effective compared with placebo. There is no clinical trial evidence directly comparing fostamatinib with rituximab or mycophenolate
  • an indirect comparison shows that fostamatinib works better than rituximab at increasing the platelets count

Reference:

• Kistangari G, McCrae KR. Immune thrombocytopenia. Hematol Oncol Clin North Am. 2013 Jun;27(3):495-520.
• Paik J. Fostamatinib: A Review in Chronic Immune Thrombocytopenia. Drugs. 2021 Jun;81(8):935-943
• NICE (October 2022). Fostamatinib for treating refractory chronic immune thrombocytopenia