title: Durable responses after ibritumomab tiuxetan radioimmunotherapy for CD20+ B-cell lymphoma: long-term follow-up of a phase 1/2 study.
abstract: We previously demonstrated that yttrium-90 (Y-90) ibritumomab tiuxetan (Zevalin) radioimmunotherapy (RIT) was safe and effective for relapsed or refractory CD20(+), B-cell, non-Hodgkin lymphoma (NHL). We now provide long-term follow-up data in responding patients based on International Workshop Response Criteria. Complete (CR), CR unconfirmed (CRu), and partial response (PR) rates were 29%, 22%, and 22%, respectively (overall response rate 73%, 51% in CR/CRu). Mean time to progression (TTP) and duration of response (DR) in responders were 12.6 months and 11.7 months, respectively. At the maximum tolerated dose (0.4 mCi/kg [14.8 MBq/kg]), TTP and DR in complete responders (CR/CRu) were 28.3 and 27.5 months, respectively. Nine patients (24% of responding patients) had a TTP of more than 3 years. Long-term responders (> 5 years) have been identified. Ibritumomab tiuxetan produces durable responses in patients with indolent and diffuse large B-cell lymphoma.
authors.affiliation: Division of Hematology/Oncology, Northwestern University Feinberg School of Medicine, 676 N St Clair, Ste 850, Chicago, IL 60611, USA. l-gordon@northwestern.edu
authors.forename: Leo I
authors.initials: LI
authors.lastname: Gordon
authors.forename: Arturo
authors.initials: A
authors.lastname: Molina
authors.forename: Thomas
authors.initials: T
authors.lastname: Witzig
authors.forename: Christos
authors.initials: C
authors.lastname: Emmanouilides
authors.forename: Andrew
authors.initials: A
authors.lastname: Raubtischek
authors.forename: Mohamed
authors.initials: M
authors.lastname: Darif
authors.forename: Russell J
authors.initials: RJ
authors.lastname: Schilder
authors.forename: Greg
authors.initials: G
authors.lastname: Wiseman
authors.forename: Christine A
authors.initials: CA
authors.lastname: White
mesh_terms: D000911:Antibodies, Monoclonal / Q000009:adverse effects / Q000627:therapeutic use*; D015703:Antigens, CD / Q000276:immunology; D018951:Antigens, CD20 / Q000276:immunology; D018450:Disease Progression; D018572:Disease-Free Survival; D005500:Follow-Up Studies; D006801:Humans; D016393:Lymphoma, B-Cell / Q000532:radiotherapy*; D016499:Radioimmunotherapy / Q000009:adverse effects*; D013997:Time Factors; D015021:Yttrium Radioisotopes / Q000627:therapeutic use*
chemical_list: D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D018951:Antigens, CD20; D015021:Yttrium Radioisotopes; C422802:ibritumomab tiuxetan