title: Long-term follow-up of patients with hypereosinophilic syndrome treated with Alemtuzumab, an anti-CD52 antibody.
abstract: BACKGROUND
  Relapsing, refractory patients with idiopathic hypereosinophilic syndrome (I-HES) and chronic eosinophilic leukemia-not otherwise specified (CEL-NOS) do not have many effective, durable therapeutic options. Alemtuzumab, an anti-CD52 antibody, has been reported to be an effective therapy due to inherent expression of CD52 on eosinophils.
  
  
  METHODS
  A retrospective chart review of 12 patients treated with alemtuzumab at our center until 2012.
  
  
  RESULTS
  Ten (83%) of 12 patients achieved complete hematologic response (CHR) after a median of 1 week for a median duration of 66 weeks, with the elimination of disease-related symptoms; 2 patients achieved partial hematologic remission hematologic remission (PHR). Patients with CHR who received alemtuzumab maintenance (n = 5) had a significantly longer time to progression than those patients who were only observed (n = 5) (P = .01). Eleven patients relapsed (only one while on maintenance), and 6 were rechallenged with alemtuzumab. Five (83%) achieved second CHR after a median of 3.5 weeks, for a median duration of 123 weeks. Again, those given maintenance (n = 3) had a longer time to progression than those who were only observed (P = .04). Adverse effects were mostly related to infusion reactions and lymphopenia-related viral infections (despite antibiotic prophylaxis). One patient developed Epstein-Barr virus-related lymphoma.
  
  
  CONCLUSIONS
  Alemtuzumab is an effective treatment for patients with relapsed, refractory idiopathic hypereosinophilic syndrome and chronic eosinophilic leukemia-not otherwise specified, in terms of both CHR achievement (even after repeated rechallenges) and duration (particularly if provided as a maintenance therapy). Common adverse effects are related to infusion reactions and immunosuppression.
authors.affiliation: Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Paolo
authors.initials: P
authors.lastname: Strati
authors.forename: Jorge
authors.initials: J
authors.lastname: Cortes
authors.forename: Stefan
authors.initials: S
authors.lastname: Faderl
authors.forename: Hagop
authors.initials: H
authors.lastname: Kantarjian
authors.forename: Srdan
authors.initials: S
authors.lastname: Verstovsek
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000074323:Alemtuzumab; D061067:Antibodies, Monoclonal, Humanized / Q000008:administration & dosage*; D000970:Antineoplastic Agents / Q000008:administration & dosage*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D017681:Hypereosinophilic Syndrome / Q000188:drug therapy* / Q000276:immunology; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies
chemical_list: D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents; D000074323:Alemtuzumab