title: Repeated short-term use of eltrombopag in patients with chronic immune thrombocytopenia (ITP).
abstract: Eltrombopag is a thrombopoietin-receptor agonist that stimulates platelet production and increases platelet counts in patients with chronic immune thrombocytopenia (ITP). This open-label, single-arm study evaluated consistency of response and safety following repeated intermittent dosing of eltrombopag 50 mg daily over 3 cycles (1 cycle = up to 6 weeks on therapy followed by up to 4 weeks off therapy). The primary endpoint was proportion of patients with a response (platelet count ≥50 × 10(9) /l and ≥2× baseline) in Cycle 1 who subsequently responded in Cycle 2 or 3. Fifty-two of 65 evaluable patients (80%) responded in Cycle 1; these responding patients comprised the primary analysis population. Of these, 45/52 (87%) responded in Cycle 2 or 3 [95% confidence interval (CI), 74-94%] and 34/48 (71%; 95% CI, 56-83%) responded in both Cycles 2 and 3. Time to response was consistent, with >50% of responders responding by Day 8 in each cycle. Bleeding rates relative to baseline decreased by approximately 50% during each treatment cycle. The frequency or severity of adverse events, most commonly headache, did not increase over successive cycles. If a chronic ITP patient not requiring consistent therapy responds to short-term eltrombopag, then subsequent courses of eltrombopag, as needed, are likely to be safe and effective.
authors.affiliation: Weill Medical College of Cornell University, New York, NY 10021, USA. jbussel@med.cornell.edu
authors.forename: James B
authors.initials: JB
authors.lastname: Bussel
authors.forename: Mansoor N
authors.initials: MN
authors.lastname: Saleh
authors.forename: Sandra Y
authors.initials: SY
authors.lastname: Vasey
authors.forename: Bhabita
authors.initials: B
authors.lastname: Mayer
authors.forename: Michael
authors.initials: M
authors.lastname: Arning
authors.forename: Nicole L
authors.initials: NL
authors.lastname: Stone
mesh_terms: D000328:Adult; D000368:Aged; D001565:Benzoates / Q000008:administration & dosage* / Q000009:adverse effects; D002908:Chronic Disease; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D005260:Female; D006397:Hematinics; D006801:Humans; D006834:Hydrazines / Q000008:administration & dosage* / Q000009:adverse effects; D008297:Male; D008875:Middle Aged; D010976:Platelet Count; D016553:Purpura, Thrombocytopenic, Idiopathic / Q000188:drug therapy*; D011720:Pyrazoles / Q000008:administration & dosage* / Q000009:adverse effects; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D001565:Benzoates; D006397:Hematinics; D006834:Hydrazines; D011720:Pyrazoles; C520809:eltrombopag