About: Tositumomab is a research topic. Over the lifetime, 232 publications have been published within this topic receiving 11347 citations. The topic is also known as: Ig gamma-1 chain C region & Bexxar.
TL;DR: Radioimmunotherapy with (90)Y ibritumomab tiuxetan is well tolerated and produces statistically and clinically significant higher ORR and CR compared with rituximab alone.
Abstract: PURPOSE: Radioimmunotherapy combines biologic and radiolytic mechanisms to target and destroy tumor cells, thus offering a needed therapeutic alternative for refractory non-Hodgkin’s lymphoma (NHL) patients. This phase III randomized study compares the novel radioimmunotherapy yttrium-90 (90Y) ibritumomab tiuxetan with a control immunotherapy, rituximab, in 143 patients with relapsed or refractory low-grade, follicular, or transformed CD20+ transformed NHL. PATIENTS AND METHODS: Patients received either a single intravenous (IV) dose of 90Y ibritumomab tiuxetan 0.4 mCi/kg (n = 73) or rituximab 375 mg/m2 IV weekly for four doses (n = 70). The radioimmunotherapy group was pretreated with two rituximab doses (250 mg/m2) to improve biodistribution and one dose of indium-111 ibritumomab tiuxetan for imaging and dosimetry. The primary end point, overall response rate (ORR), was assessed by an independent, blinded, lymphoma expert panel. RESULTS: ORR was 80% for the 90Y ibritumomab tiuxetan group versus 56% for ...
TL;DR: A single one-week course of 131I-tositumomab therapy as initial treatment can induce prolonged clinical and molecular remissions in patients with advanced follicular lymphoma.
Abstract: Background Advanced-stage follicular B-cell lymphoma is considered incurable. Anti-CD20 radioimmunotherapy is effective in patients who have had a relapse after chemotherapy or who have refractory follicular lymphoma, but it has not been tested in previously untreated patients. Methods Seventy-six patients with stage III or IV follicular lymphoma received as initial therapy a single course of treatment with 131I-tositumomab therapy (registered as Tositumomab and Iodine I 131 Tositumomab [the Bexxar therapeutic regimen]). This consisted of a dosimetric dose of tositumomab and 131I-labeled tositumomab followed one week later by a therapeutic dose, delivering 75 cGy of radiation to the total body. Results Ninety-five percent of the patients had any response, and 75 percent had a complete response. The use of polymerase chain reaction (PCR) to detect rearrangement of the BCL2 gene showed molecular responses in 80 percent of assessable patients who had a clinical complete response. After a median follow-up of ...
TL;DR: Ibritumomab tiuxetan radioimmunotherapy is effective in rituximab-refractory patients and the only significant toxicity is hematologic.
Abstract: PURPOSE: Rituximab is commonly used as a single agent or in combination therapy for non-Hodgkin’s lymphoma (NHL). Ibritumomab tiuxetan radioimmunotherapy targets the same antigen as rituximab and has demonstrated efficacy in rituximab-naive NHL. This study evaluated ibritumomab tiuxetan in the treatment of rituximab-refractory follicular NHL. PATIENTS AND METHODS: Eligible patients were refractory to rituximab; this was defined as no objective response to rituximab (375 mg/m2 weekly for 4 weeks) or time to progression (TTP) of ≤ 6 months. The ibritumomab tiuxetan treatment regimen consisted of pretreatment with rituximab (250 mg/m2 intravenously on days 1 and 8) to deplete peripheral blood B cells, then yttrium-90 ibritumomab tiuxetan (0.4 mCi/kg; maximum, 32 mCi) intravenously on day 8, administered on an outpatient basis. An imaging/dosimetry dose of indium-111 ibritumomab tiuxetan (5 mCi) was injected after rituximab (day 1) in 28 patients. RESULTS: Fifty-seven patients were treated. The median age was...
TL;DR: High-dose treatment with (131)I-Tositumomab, etoposide, and cyclophosphamide results in a high remission rate and may provide long-term disease-free survival for patients with relapsed or refractory mantle cell lymphoma.
TL;DR: Support is given for the use of type II CD20 mAbs in human B-cell diseases because type I mAbs mutated in the Fc domain (K322A) to prevent C1q binding still did not display equivalent efficacy.