title: Review article: pharmacological approaches for the treatment of thrombocytopenia in patients with chronic liver disease and hepatitis C infection.
abstract: BACKGROUND
  Patients with chronic liver disease and hepatitis C virus (HCV) frequently experience thrombocytopenia that complicates the management of their disease. Traditional therapy for thrombocytopenia consists of platelet transfusion, which can be associated with significant safety and economic issues. Consequently, efforts have been directed toward developing novel approaches for the treatment of thrombocytopenia.
  
  
  OBJECTIVE
  To summarize the available data on the limitations of traditional therapies and the effects of novel therapies currently in clinical development for the treatment of thrombocytopenia.
  
  
  RESULTS
  Recent research has begun to reveal the complex mechanisms that regulate thrombopoiesis. Cytokines and growth factors, such as interleukin-11 and thrombopoietin (TPO), play a key role in the production of platelets. A number of recent clinical studies have provided evidence that pharmacologic agents that target megakaryocyte precursors and stimulate thrombopoiesis can effectively reverse thrombocytopenia. Here, we review the regulation of thrombopoiesis, the role of TPO, and a number of novel compounds that stimulate platelet production by acting through the TPO receptor. Agents that stimulate TPO include the orally available nonpeptidic agonists eltrombopag and AKR-501, peptidic agonists AMG-531 and Peg-TPOmp, and small engineered antibodies.
  
  
  CONCLUSIONS
  Results from clinical trials with these agents in healthy subjects confirm that activation of thrombopoiesis via the TPO pathway is an effective method of stimulating platelet production. This approach may provide safer, more effective treatment for thrombocytopenia in patients with chronic liver disease. Several of these agents are currently being tested in large scale trials.
authors.affiliation: Beth Israel Deaconess Medical Center, Boston, MA 02215, USA. nafdhal@bidmc.harvard.edu
authors.forename: N H
authors.initials: NH
authors.lastname: Afdhal
authors.forename: J G
authors.initials: JG
authors.lastname: McHutchison
mesh_terms: D000998:Antiviral Agents / Q000627:therapeutic use*; D002908:Chronic Disease; D016207:Cytokines / Q000627:therapeutic use; D006397:Hematinics / Q000627:therapeutic use*; D006526:Hepatitis C / Q000150:complications*; D006801:Humans; D008107:Liver Diseases / Q000150:complications*; D010346:Patient Care Management; D053628:Receptors, Thrombopoietin / Q000819:agonists / Q000627:therapeutic use; D013921:Thrombocytopenia / Q000188:drug therapy* / Q000209:etiology
chemical_list: D000998:Antiviral Agents; D016207:Cytokines; D006397:Hematinics; D053628:Receptors, Thrombopoietin; C082218:MPL protein, human