Ibritumomab tiuxetan radioimmunotherapy for patients with relapsed or refractory non-Hodgkin lymphoma and mild thrombocytopenia: a phase II multicenter trial.
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.
Wiseman
Gregory A
GA
Division of Nuclear Medicine, Mayo Clinic, Rochester, MN 55905, USA. gwiseman@mayo.edu
Gordon
Leo I
LI
Multani
Pratik S
PS
Witzig
Thomas E
TE
Spies
Stewart
S
Bartlett
Nancy L
NL
Schilder
Russell J
RJ
Murray
James L
JL
Saleh
Mansoor
M
Allen
Roberta S
RS
Grillo-López
Antonio J
AJ
White
Christine A
CA
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
D000911:Antibodies, Monoclonal; D000970:Antineoplastic Agents; D015021:Yttrium Radioisotopes; C422802:ibritumomab tiuxetan