Brian,Nigel and Gary, This is an excerpt from reuters tonight.
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12/05 6:44P (RT) CORRECTED - Radioactive antibodies effective against
lymphoma-studies
DRUGS HAVE SIDE EFFECTS
Zevalin, however, is particularly toxic to delicate bone
marrow tissue, according to IDEC.
"Almost any type of radiation has the potential to damage
bone marrow. We don't treat patients with Zevalin that have had
more than 25 percent of their bone marrow compromised," said
Connie Matsui, senior vice president of planning and resource
development at IDEC.
Kari Nadeau, director of medical research at Coulter, said
Bexxar is less toxic than Zevalin because yttrium is absorbed
by bone marrow where it interferes with the generation of new
cells.
"Bexxar uses iodine that gets taken up by the kidneys," and
is passed as urine she said.
Matsui at IDEC said, "Our philosophy is that patients
should receive Rituxan or chemotherapy plus Rituxan as
first-line therapy."
IDEC currently co-markets Rituxan with Genentech Inc.
<DNA.N> as a treatment for patients with the low-grade form of
the disease who have failed to benefit from standard care like
chemotherapy.
In a late-stage trial of Zevalin in 54 patients who had not
responded to Rituxan, 74 percent of the patients experienced at
a least a 50-percent reduction in tumor size, while 15 percent
went into remission, according to the study's leader Dr. Thomas
Witzig, of the Mayo Clinic in Rochester, Minnesota.
But 35 percent of patients in this study experienced
decreased white blood cell counts and 9 percent had decreased
blood platelets, he said.
"The complete response rate is high...but there are some
toxicity concerns," said Gwen Fyfe, senior director of oncology
at Genentech. Drugs like Zevalin are most important for
patients with relapsed disease, she said.
In a late-stage study of 40 patients previously treated
with Rituxan, Bexxar reduced tumor size by more than half in 70
percent of patients and 40 percent had no signs of the cancer, |
