Zevalin Shows No Activity in Richter's Patients

[Guest guest]

[unfortunate, indeed. Note the qualifiers that these were

all 'heavily' pre-treated patients, though the range of treatments

was 1-7, five treatments being average. I'm not sure one treatment

makes a person 'heavily' pre-treated, but...]

Cancer. 2004 May 15;100(10):2195-200.

Yttrium-90 ibritumomab tiuxetan radioimmunotherapy in Richter

syndrome.

Tsimberidou AM, Murray JL, O'Brien S, Wierda WG, Keating MJ.

Department of Leukemia, The University of Texas M. D. Cancer

Center, Houston, Texas.

BACKGROUND: (90)Y ibritumomab tiuxetan is a radioimmunotherapeutic

construct that is reported to be an effective treatment for patients

with lymphoma. The aim of the current analysis was to evaluate

retrospectively the efficacy and safety of (90)Y ibritumomab tiuxetan

in patients with Richter syndrome (RS).

METHODS: Patients with histologically proven CD20-positive RS and <

25% lymphoma and/or chronic lymphocytic leukemia in the bone marrow

were treated. Patients received an imaging dose of (111)In-labeled

ibritumomab tiuxetan of 1.6 mg (5.0 mCi of (111)In) intravenously.

One week later, they received 0.3 or 0.4 mCi/kg of (90)Y ibritumomab

tiuxetan. Rituximab, at a dose of 250 mg/m(2) intravenously, was

given immediately before ibritumomab tiuxetan on Days 1 and 8.

RESULTS: Seven patients were treated. Their median age was 56 years

(range, 44-70 years). The median time to transformation was 7.9 years

(range, 0.7-28.4 years). The median number of previous therapies

received was five (range, one to seven previous therapies). The

median number of previous therapies received for RS was one (range,

none to three previous therapies).

Six patients were treated previously with hyperfractionated

cyclophosphamide, vincristine, doxorubicin, and dexamethasone

alternating with methotrexate and cytosine arabinoside.

No patient responded to (90)Y ibritumomab tiuxetan therapy. All

patients developed disease progression. The median time to disease

progression was 41 days (range, 39-89 days). Side effects included

hematologic toxicity. Grade 3-4 (according to the second version of

the National Cancer Institute Common Toxicity Criteria)

thrombocytopenia and neutropenia occurred in 5 patients (71%) and 2

patients (29%), respectively. There was one episode of septic shock

in a patient with Grade 4 neutropenia.

CONCLUSIONS: (90)Y ibritumomab tiuxetan had no significant antitumor

activity and hematologic toxicity was severe in these heavily

pretreated patients with RS.

Cancer 2004. Copyright 2004 American Cancer Society.

PMID: 15139064 [PubMed - in process]