Health Canada Approves Treatment for Two Indications in Thrombocytopenia

Health Canada on Monday approved avatrombopag (doptelet, Sobi) to treat thrombocytopenia in adult patients with chronic immune thrombocytopenia (ITP) and in adult patients with chronic liver disease (CLD) who are scheduled to undergo an invasive procedure.

Avatrombopag is an oral thrombopoietin (TPO) receptor agonist that stimulates the proliferation and differentiation of megakaryocytes from bone marrow progenitor cells, resulting in increased production of platelets. It does not compete with TPO for binding to the TPO receptor.

Health Canada based these approvals on results from several clinical trials. In a phase 3 study of adult patients with immune thrombocytopenia, administration of avatrombopag resulted in a platelet count of at least 50,000 per μL at day eight of therapy in most patients. Avatrombopag was superior to placebo in maintaining platelet counts in the target range during the six-month treatment period.

Among patients with thrombocytopenia and CLD, findings from the phase 3 ADAPT-1 and ADAPT-2 trials demonstrated that the proportion of patients not requiring a platelet transfusion or any rescue procedure for bleeding was significantly higher in the two avatrombopag-treated groups.

In the United States, the Food and Drug Administration approved avatrombopag to treat adult patients with thrombocytopenia in adult patients with CLD in 2018 and in adults with chronic ITP who have had an insufficient response to a previous treatment in 2019.