GlaxoSmithKline received approval from the FDA for Promacta (eltrombopag) for the treatment of thrombocytopenia in patients with chronic immune (idiopathic) thrombocytopenic purpura (ITP) who have had an insufficient response to corticosteroids, immunoglobulins or splenectomy. Promacta is the first oral thrombopoietin (TPO) receptor agonist therapy for the treatment of adult patients with chronic ITP.
    
Chronic ITP is a bleeding disorder marked by increased platelet destruction and/or inadequate platelet production in the blood. Promacta has been shown to stimulate cells in the bone marrow to produce platelets.
   
As a result of the approval, Ligand Pharmaceuticals will be entitled to receive a $2 million milestone payment from GSK. Ligand will also earn royalties in the range of 5%-10% on annual sales of the drug.
   
GSK also reported positive Phase II data in patients with thrombocytopenia associated with hepatitis C and initiated two Phase III trials in patients with hepatitis C in 4Q07. A Phase II study in patients with chemotherapy-induced thrombocytopenia has been completed, a Phase III study is ongoing in chronic liver disease and a Phase I study is ongoing in patients with sarcoma receiving the adriamycin and ifosfamide regimen. GSK expects an MAA submission for the long-term treatment of ITP by the end of the year.