Cancer drug prolongs life for sickle cell patients, study says
Tuesday, April 1st 2003, 12:00 am
By: News On 6
CHICAGO (AP) _ A drug that reduces the disabling pain of sickle cell anemia can also significantly lower death rates and should be used by many more patients with the blood disorder, researchers say.
The drug, hydroxyurea, is more often associated with cancer and AIDS treatments and most sickle cell patients who need it aren't getting it, said Dr. Duane Bonds of the National Heart, Lung and Blood Institute.
In a government-funded study of adult sickle cell patients co-authored by Bonds, those who used hydroxyurea capsules at least periodically for nine years were 40 percent less likely to die during the study than those who never used the drug.
``Now there is new hope for these patients, who typically die 10 to 15 years earlier than patients with milder cases,'' said Dr. Claude Lenfant, the institute director.
The study appears in Wednesday's Journal of the American Medical Association. It covered 299 patients, but complete data was only recorded for 233 of them. Complete data were available for 233 of the 299 participants.
Sickle cell anemia, an inherited blood disorder, affects about 72,000 Americans, mostly blacks. Patients have defective hemoglobin, oxygen-carrying blood protein, which causes deformed red blood cells that can clog vessels. This deprives organs and tissues of adequate blood supply, causing severe pain.
Hydroxyurea reduces painful episodes by increasing levels of a type of hemoglobin that improves blood flow.
There were 13 deaths among the 36 patients who never took hydroxyurea, compared with 21 deaths among the 106 patients who took the drug throughout the nine-year period. The 40 percent difference was calculated using an average of death rates for every three-month period in the study, Bonds said.
Follow-up research shows the benefits extend to prolonging life in moderately to severely affected patients, who make up some 30 percent of sickle cell patients, said Dr. Martin Steinberg of Boston University, the lead researcher. Most are not taking the drug but should be, he said.
The drug costs about $100 monthly. There are possible side effects, including a potentially increased risk of leukemia and a decrease in blood cell counts, which could make patients prone to infections.
None of the study participants developed leukemia and blood cell decreases can be managed with proper monitoring, Steinberg said.
Bonds said the potent drug may be underused because it's ``more work for doctors,'' requiring frequent patient visits to adjust dosages and make sure complications don't develop.
``Patients should be reassured,'' Bonds said. ``This is an effective and safe therapy.''
Dr. Michael Levien, a pediatric hematologist at Cleveland Clinic Foundation, said the study's results are significant and should encourage expanded use of hydroxyurea.
``It's a very, very important drug. It just has to be used properly,'' Levien said.
Patients are generally advised to take the capsules daily. Study participants took either hydroxyurea or dummy pills in the first phase, from 1992-95. In the follow-up, from 1996-2001, researchers observed results in patients who continued, stopped or started taking hydroxyurea.