title: Safety and efficacy of eltrombopag for treatment of chronic immune thrombocytopenia: results of the long-term, open-label EXTEND study.
abstract: Patients with chronic immune thrombocytopenia may have bleeding resulting from low platelet counts. Eltrombopag increases and maintains hemostatic platelet counts; however, to date, outcome has been reported only for treatment lasting ≤ 6 months. This interim analysis of the ongoing open-label EXTEND (Eltrombopag eXTENded Dosing) study evaluates the safety and efficacy of eltrombopag in 299 patients treated up to 3 years. Splenectomized and nonsplenectomized patients achieved platelets ≥ 50 000/μL at least once (80% and 88%, respectively). Platelets ≥ 50 000/μL and 2 × baseline were maintained for a median of 73 of 104 and 109 of 156 cumulative study weeks, respectively. Bleeding symptoms (World Health Organization Grades 1-4) decreased from 56% of patients at baseline to 20% at 2 years and 11% at 3 years. One hundred (33%) patients were receiving concomitant treatments at study entry, 69 of whom attempted to reduce them; 65% (45 of 69) had a sustained reduction or permanently stopped ≥ 1 concomitant treatment. Thirty-eight patients (13%) experienced ≥ 1 adverse events leading to study withdrawal, including patients meeting protocol-defined withdrawal criteria (11 [4%] thromboembolic events, 5 [2%] exceeding liver enzyme thresholds). No new or increased incidence of safety issues was identified. Long-term treatment with eltrombopag was generally safe, well tolerated, and effective in maintaining platelet counts in the desired range.
authors.affiliation: Georgia Cancer Specialists, 5408 St Lyonn Pl, Marietta, GA 30068, USA. mansoor.saleh@ccc.uab.edu
authors.forename: Mansoor N
authors.initials: MN
authors.lastname: Saleh
authors.forename: James B
authors.initials: JB
authors.lastname: Bussel
authors.forename: Gregory
authors.initials: G
authors.lastname: Cheng
authors.forename: Oliver
authors.initials: O
authors.lastname: Meyer
authors.forename: Christine K
authors.initials: CK
authors.lastname: Bailey
authors.forename: Michael
authors.initials: M
authors.lastname: Arning
authors.forename: Andres
authors.initials: A
authors.lastname: Brainsky
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001565:Benzoates / Q000008:administration & dosage* / Q000009:adverse effects*; D001792:Blood Platelets / Q000166:cytology / Q000187:drug effects; D001855:Bone Marrow Diseases / Q000150:complications; D002908:Chronic Disease; D005260:Female; D019337:Hematologic Neoplasms / Q000150:complications; D006470:Hemorrhage / Q000150:complications; D006801:Humans; D006834:Hydrazines / Q000008:administration & dosage* / Q000009:adverse effects*; D008107:Liver Diseases / Q000150:complications; D008297:Male; D008875:Middle Aged; D010976:Platelet Count; D016553:Purpura, Thrombocytopenic, Idiopathic / Q000150:complications / Q000188:drug therapy*; D011720:Pyrazoles / Q000008:administration & dosage* / Q000009:adverse effects*; D053628:Receptors, Thrombopoietin / Q000819:agonists*; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D001565:Benzoates; D006834:Hydrazines; D011720:Pyrazoles; D053628:Receptors, Thrombopoietin; C082218:MPL protein, human; C520809:eltrombopag