Thrombopoietin Receptor Agonists in Immune Thrombocytopenia

1. Kristen Sanfilippo M.D. Thrombopoietin Receptor Agonists in Immune Thrombocytopenia

2. ITP Definition Autoimmune disorder characterized by immunologic destruction and decreased production of otherwise normal platelets most commonly occurring in response to an unknown stimulus. Primary Secondary (i.e. HIV, HCV, and antiphospholipid ab syndrome) PLT count of < 100,000 or 150,0007 New (< 3 months) Persistent (3 to 12 months) Chronic (> 12 months) Majority of Studies Use PLT < 150,000 for inclusion/exclusion criteria

3. ITP Treatment Treatment Goal: Prevention of bleeding events No clear data exists Severity of Bleeding Bleeding Risks (prior bleeding episodes, HTN, age) Activity Level Side Effects of Treatment ASH 2011 Guidelines: PLT < 30,000 (Grade 2C)

4. First Line Treatment Summary Longer course of corticosteroids are preferred over shorter courses of corticosteroids or IVIg as first line treatment (grade 2B) If IVIg is used, the dose should initially be 1g/kg as a onetime dose. This dosage may be repeated if necessary (Grade 2B) IVIg be used with corticosteroids when a more rapid increase in platelet count is required (Grade 2B) Either IVIg or anti-D (in appropriate patients) be used as a first line treatment if corticosteroids are contraindicated (Grade 2C)

5. Relapsed or Refractory ITP Refractory ITP: Severe ITP (ITP resulting in clinically relevant bleeding) that occurs after a splenectomy Relapsed ITP: Occurs after initial therapy, or with failure to achieve an adequate PLT response with initial therapy