FDA looks at anemia drugs, cancer risks

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FDA looks at anemia drugs, cancer risks

Last Updated: 2004-03-19 11:29:05 -0400 (Reuters Health)

By Richwine

WASHINGTON (Reuters) - U.S. regulators are considering whether two

anemia-fighting drugs, often given to cancer patients, may in some cases

stimulate tumor growth, a question raised by studies of similar products

sold in Europe.

The Food and Drug Administration has scheduled a meeting of outside

experts for May 4 to gather input on safety issues surrounding the

medicines, Amgen Inc.'s Aranesp and & 's Procrit.

The agency still believes the drugs are safe, and a valuable alternative

to blood transfusions, when used as directed for treating anemia in

patients receiving chemotherapy.

The treatments are bioengineered versions of a human protein,

erythropoietin, that stimulate production of red blood cells. Combined

sales of the anemia drugs, which are given by injection, amount to

several billion dollars a year.

The medicines are prescribed for patients with cancer, kidney disease

and other ailments to treat anemia, a deficiency of red blood cells that

causes fatigue and other symptoms.

In the studies of the European products, the drugs were used differently

to see if they might help fight cancer by boosting effectiveness of

chemotherapy or radiation. Some patients received higher than normal

doses, and some were not anemic.

The FDA wants advice from its outside advisory committee on whether

those studies are relevant to the U.S. products, and whether more

research on possible tumor effects is needed, an agency official said.

One study last year found patients undergoing radiation treatment for

head and neck cancer had shorter survival times if they took Roche AG's

NeoRecormon, the company's anemia treatment sold in Europe.

Another trial of breast cancer patients undergoing chemotherapy was

halted early because of higher mortality among those given &

's Eprex, also sold in Europe. Survival at 12 months was 76

percent in patients given a placebo, and 70 percent among patients

treated with Eprex.

Some deaths resulted from progression of cancer, and others from blood

clots, a known risk, the researchers said.

Researchers said the findings were not definitive but did raise

concerns.

Amgen has " fully examined all of our data, and we find no evidence of

(tumor stimulation) with Aranesp, " Amgen spokeswoman Stoddard

said.

She said the studies of the European products were not pertinent to

Aranesp because they involved different drugs.

& spokesman Mark Wolfe said the company was committed to

providing patients and health-care providers " with the most complete and

up-to-date information regarding the safe use of this important class of

medications. "

He declined to comment further.

Researchers do not know why the anemia drugs might prompt tumors to

grow, but some theorize they might activate some receptors on tumors

that help spur growth.

I'll tell you where to go!

Mayo Clinic in Rochester

http://www.mayoclinic.org/rochester

s Hopkins Medicine

http://www.hopkinsmedicine.org