If this is not your name, click here.
| | If this is not your name, click here. | | |
| | Contact Us | Order Now | Journals | Bookstore | Register a colleague | | |
| |  ASTRO: Radiolabeled Antibody Safe in Lymphoma Patients Treated With Radiation By Emma Hitt Special to DG News NEW ORLEANS, LA -- October 10, 2002 -- Ibritumomab tiuxetan (Zevalin, IDEC Pharmaceuticals) appears to be safe for patients with CD20-positive B-cell lymphoma that have previously been treated with radiation therapy. Ibritumomab tiuxetan recently became the first radiolabeled antibody to receive United States Food and Drug Administration approval for use in relapsed and refractory low grade CD20+ B cell lymphoma. It incorporates the beta-emitter yttrium-90 with a monoclonal antibody directed against the CD20 antigen expressed on B cells. Dr. Roger Macklis, chairman of the department of radiation oncology at the Cleveland Clinic Foundation, in Cleveland, Ohio, United States, presented the findings October 9 at the American Society for Therapeutic Radiology and Oncology (ASTRO) 44th Annual Meeting. According to the researchers, the safety of this compound has been a concern because ibritumomab tiuxetan has been associated with haemopoietic suppression and thrombocytopenia. To test the safety of ibritumomab tiuxetan, the researchers evaluated 211 patients, 60 of which had received prior radiation therapy and 151 of which had not. The patients groups were similar, except the radiation therapy group generally showed a lower rate of marrow involvement (p<0.01), less advanced disease stage (p<0.02), and a longer interval from the time of diagnosis to the time of radioimmunotherapy treatment (p<0.01). They found that patients who had received prior radiation therapy responded as well to ibritumomab tiuxetan as those who had not, based on subsequent presence or absence of most types of organ-specific toxicity. However, toxicity in the brain and lungs suggested a trend (p=0.07) towards an association between prior radiation therapy and toxicity. But Dr. Macklis pointed out that some of the patients who experienced toxicity in these areas had not received external beam treatment to the area in question, and therefore the toxicity may have been unrelated to treatment. In the future, studies will evaluate low-dose Zevalin (0.1 mCi/kg) in the treatment of non-Hodgkin’s lymphoma patients (NHL) patients whose marrow cannot tolerate full-dose Zevalin (0.3 to 0.4 mCi/kg), said Dr. Macklis, as well as concurrent involved field radiotherapy and rituximab immunotherapy in patients with refractory indolent NHL. Although the treatment is specific to CD20 positive B cells, he noted, "this general approach may have wide applicability to other tumor types."
|
