Leukemia Pill Shows Promise
More than three years ago Bud Romine read an article about a cutting-edge cancer therapy that was being created practically in his own backyard.
He soon became one of the first patients to take an experimental new pill to fight against one form of leukemia, reports Correspondent Kris Eisenhauer of CBS affiliate KOIN-TV in Portland, Oregon.
It could prove to be the first major treatment for the disease in 13 years.
The drug, called STI-571, is intended to treat chronic myelogenous leukemia, which accounts for about 4,300 of the 30,000 new cases of leukemia in the United States each year, according to the Leukemia Society of America.
"There's a lot of attention focused on this because this is really one of the first times we've been able to go from the lab -- identifiying abnormalities and targeting a drug against the abnormality into patient trials," says Dr. Brian J. Druker of the Oregon Health Sciences University.
Romine has been battling CML for more than five years now. After age 50, the risks of getting a transplant outweighed the benefits. Taking the experimental drug was a last resort.
What makes this particular treatment so different from any other is that it destroys the cancer cells without destroying any healthy cells. A drawback to normal chemotherapy is that it doesn't care what type of cells it kills.
The good cells get it along with the bad -- weakening the immune system, making patients unable to handle the cancer.
"Without some other new from of treatment, his disease is likely to evolve into a much more aggressive leukemia that ultimately could take his life," Druker says.
The drug is still being investigated, but early results show it works. STI-571 could become the first major treatment for this kind of leukemia since interferon shots were introduced in 1986. Interferon, a natural protein that revs up the body's immune defenses, is the current standard treatment for CML and cures up to one-third of those with the disease.
However, it can take two years of daily shots of interferon to get remission. And interferon has many side effects, including pain and inflammation of the joints. The new drug's side effects are few and mild, and it is available in pill form.
The reason: The medicine is designed to stop a certain enzyme that triggers the disease. Doctors said this approach breaks new ground by targeting the particular biological defect that causes the cancer.
"This is perhaps the best example of how understanding the cause can lead to an effective treatment for cancer," said Dr. David A. Scheinberg, chief of leukemia at Memorial-Sloan Kettering Cancer Center in New York City.
The current tests in Oregon and at UCLA and the M.D. Anderson Cancer Center in Houston were designed to find out whether the drug is safe and how much the body can tolerate. Patients took daily doses of 25 to 500 milligrams.
Fifty-four people, all of whom either never responded r were no longer responding to interferon, have taken the drug for at least four weeks. The white blood cell count dropped by more than half in every patient who has taken at least 140 mg a day of the drug, and all 31 taking at least 300 mg have normal white and red blood cell counts, Druker said.
The second round of human testing will start next month with about 200 patients, with 600 more to be enrolled later that year.