title: Ibritumomab tiuxetan radioimmunotherapy for patients with relapsed or refractory non-Hodgkin lymphoma and mild thrombocytopenia: a phase II multicenter trial.
abstract: Mildly thrombocytopenic patients with relapsed or refractory low-grade non-Hodgkin lymphoma (NHL) have an increased risk of chemotherapy-induced myelosuppression following treatment. The safety and efficacy of radioimmunotherapy with a reduced dose of (90)Y ibritumomab tiuxetan (0.3 mCi/kg [11 MBq/kg]; maximum 32 mCi [1.2 GBq]) was evaluated in 30 patients with mild thrombocytopenia (100-149 x 10(9) platelets/L) who had advanced, relapsed or refractory, low-grade, follicular, or transformed B-cell NHL. The ibritumomab tiuxetan regimen included an infusion of rituximab (250 mg/m(2)) and injection of (111)In ibritumomab tiuxetan (5 mCi [185 MBq]) for dosimetry evaluation, followed 1 week later with rituximab (250 mg/m(2)) and (90)Y ibritumomab tiuxetan (0.3 mCi/kg [11 MBq/kg]). Patients (median age, 61 years; 90% stage III/IV at study entry; 83% follicular lymphoma; and 67% with bone marrow involvement) had a median of 2 prior therapy regimens (range, 1-9). Estimated radiation-absorbed doses were well below the study-defined maximum allowable for all 30 patients. With the use of the International Workshop criteria for NHL response assessment, the overall response rate was 83% (37% complete response, 6.7% complete response unconfirmed, and 40% partial response). Kaplan-Meier estimated median time to progression (TTP) was 9.4 months (range, 1.7-24.6). In responders, Kaplan-Meier estimated median TTP was 12.6 months (range, 4.9-24.6), with 35% of data censored. Toxicity was primarily hematologic, transient, and reversible. The incidence of grade 4 neutropenia, thrombocytopenia, and anemia was 33%, 13%, and 3%, respectively. Reduced-dose ibritumomab tiuxetan is safe and well tolerated and has significant clinical activity in this patient population.
authors.affiliation: Division of Nuclear Medicine, Mayo Clinic, Rochester, MN 55905, USA. gwiseman@mayo.edu
authors.forename: Gregory A
authors.initials: GA
authors.lastname: Wiseman
authors.forename: Leo I
authors.initials: LI
authors.lastname: Gordon
authors.forename: Pratik S
authors.initials: PS
authors.lastname: Multani
authors.forename: Thomas E
authors.initials: TE
authors.lastname: Witzig
authors.forename: Stewart
authors.initials: S
authors.lastname: Spies
authors.forename: Nancy L
authors.initials: NL
authors.lastname: Bartlett
authors.forename: Russell J
authors.initials: RJ
authors.lastname: Schilder
authors.forename: James L
authors.initials: JL
authors.lastname: Murray
authors.forename: Mansoor
authors.initials: M
authors.lastname: Saleh
authors.forename: Roberta S
authors.initials: RS
authors.lastname: Allen
authors.forename: Antonio J
authors.initials: AJ
authors.lastname: Grillo-López
authors.forename: Christine A
authors.initials: CA
authors.lastname: White
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000911:Antibodies, Monoclonal / Q000008:administration & dosage* / Q000493:pharmacokinetics / Q000633:toxicity; D000970:Antineoplastic Agents / Q000008:administration & dosage* / Q000493:pharmacokinetics / Q000633:toxicity; D003131:Combined Modality Therapy; D005260:Female; D006801:Humans; D008228:Lymphoma, Non-Hodgkin / Q000150:complications / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D011829:Radiation Dosage; D016499:Radioimmunotherapy; D012074:Remission Induction / Q000379:methods; D016879:Salvage Therapy; D013921:Thrombocytopenia / Q000139:chemically induced* / Q000517:prevention & control; D014018:Tissue Distribution; D016896:Treatment Outcome; D015021:Yttrium Radioisotopes / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000633:toxicity
chemical_list: D000911:Antibodies, Monoclonal; D000970:Antineoplastic Agents; D015021:Yttrium Radioisotopes; C422802:ibritumomab tiuxetan