title: Romiplostim for the treatment of chronic immune (idiopathic) thrombocytopenic purpura.
abstract: OBJECTIVE
  On August 22, 2008, Romiplostim (Nplate for Injection) received approval from the US Food and Drug Administration (FDA) 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. This report summarizes the FDA analyses of the clinical data supporting this approval.
  
  
  METHODS
  The FDA reviewed data from two double-blind, placebo-controlled clinical studies, an uncontrolled extension study, and supportive studies. In the controlled studies, enrolled patients had completed at least one prior treatment for chronic ITP and had a platelet count < or = 30 x 10(9)/L. One study enrolled patients who had undergone splenectomy; the other enrolled patients who had not undergone splenectomy. The primary endpoint in both controlled studies was durable platelet response.
  
  
  RESULTS
  Overall, 125 patients were randomized in the controlled studies. A durable platelet response was observed in 61% of nonsplenectomized patients and 38% of patients who had undergone splenectomy. One placebo group patient achieved a durable platelet response. Serious hemorrhage events were reported in 10% of placebo recipients and 6% of romiplostim recipients. In the extension study, patients received romiplostim for a median of 60 weeks and a maximum of 96 weeks; the majority of patients maintained platelet counts > or = 50 x 10(9)/L throughout the study. Major safety findings pertained to a risk for bone marrow reticulin formation and worsened thrombocytopenia following romiplostim discontinuation.
  
  
  CONCLUSIONS
  The FDA approved romiplostim for use among certain patients with chronic ITP. This approval included a Risk Evaluation and Mitigation Strategy to ensure that the benefits of the drug outweigh its risks.
authors.affiliation: Office of Oncology Drug Products, Center for Drug Evaluation and Research, US Food and Drug Administration, Silver Spring, Maryland 20993, USA.
authors.forename: Faranak
authors.initials: F
authors.lastname: Jamali
authors.forename: Steven
authors.initials: S
authors.lastname: Lemery
authors.forename: Kassa
authors.initials: K
authors.lastname: Ayalew
authors.forename: Suzanne
authors.initials: S
authors.lastname: Robottom
authors.forename: Kathy
authors.initials: K
authors.lastname: Robie-Suh
authors.forename: Dwaine
authors.initials: D
authors.lastname: Rieves
authors.forename: Richard
authors.initials: R
authors.lastname: Pazdur
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002352:Carrier Proteins / Q000627:therapeutic use*; D002908:Chronic Disease; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015990:Placebo Effect; D010976:Platelet Count; D011379:Prognosis; D016553:Purpura, Thrombocytopenic, Idiopathic / Q000188:drug therapy* / Q000601:surgery; D011961:Receptors, Fc / Q000627:therapeutic use*; D011993:Recombinant Fusion Proteins / Q000627:therapeutic use*; D013156:Splenectomy; D013926:Thrombopoietin; D016896:Treatment Outcome
chemical_list: D002352:Carrier Proteins; D011961:Receptors, Fc; D011993:Recombinant Fusion Proteins; D013926:Thrombopoietin; C488777:romiplostim