One-shot antibody treatment stalls killer lymphoma
Wed Feb 2, 2005 05:00 PM ET
By Gene Emery
BOSTON, Feb 2 (Reuters) - A single dose of antibodies laced with radioactive iodine can wipe out a usually fatal form of cancer in the lymphatic system, researchers reported on Wednesday.
A new treatment for advanced-stage follicular lymphoma known as the Bexxar therapeutic regimen was found to shrink tumors in 95 percent of patients, researchers said. And it took a fraction of the time of traditional chemotherapy with fewer side effects.
The non-Hodgkins lymphoma affects about 60,000 people in the United States and is not considered curable using traditional treatments. Even when patients initially respond to treatment, the disease almost always comes back and becomes more difficult to treat.
Lymphoma is a cancer that affects immune cells in the lymphatic system, which helps filter out germs and is important in fighting disease.
The Bexxar treatment is already approved for people with follicular lymphoma once conventional chemotherapy has failed. The study, published in this week's New England Journal of Medicine, was designed to see if the treatment should be given as a first line of attack.
Lead study author Mark Kaminski of the University of Michigan Comprehensive Cancer Center said the results rival any treatment for follicular lymphoma, including chemotherapy. The Bexxam therapy takes about a week to complete compared to many months for chemotherapy regimens.
"This (antibody) drug has been primarily relegated by most clinicians as a last-ditch effort," Kaminski told Reuters. "What this is showing is if you treat the patients earlier, you get much more durable remissions without having to put the patient through chemotherapy after chemotherapy."
75 PER CENT SUCCESS RATE
Bexxar, marketed in the United States by GlaxoSmithKline (GSK.L: Quote, Profile, Research) , combines an antibody that seeks out cancer cells, and a radioactive form of the element iodine.
When injected, it travels through the bloodstream to bind to a protein found on the surface of the cancerous cells. The radiation zaps these malignant cells with minimal exposure to normal tissues.
The researchers said that in 75 percent of patients treated with Bexxar, all traces of the cancer disappeared. And more than three-quarters of patients with a complete remission were disease-free after five years.
While the latest findings may appear promising, they are not definitive because the treatment was not compared to conventional chemotherapy.
In an editorial in the Journal, Joseph Connors of the British Columbia Cancer Agency, said the results are not impressive enough to make Bexxar a first-line treatment -- at least not without further study.
Connors said the study tested the treatment on "a highly selected group of younger-than-average patients" who did not have a lot of cancer to start with, and what they did have was growing fairly slowly.
But Kaminski said he hopes the results will "move this to the front burner instead of relegating it to the back burner."
The antibody treatment, also known as tositumomab, costs about $26,000 to $28,000, roughly equivalent to the price of extended chemotherapy, said Kaminski. Connors characterized this as "potentially very expensive."... |
