An experimental cancer drug that works after a single round of treatment appears to be the most effective medicine yet for a rare form of leukemia, according to a study. The drug _ called 2-chlorodeoxyadenosine, or 2-CdA _ has produced complete remissions in almost all hairy cell leukemia patients treated, and none has relapsed so far. Researchers who developed and tested the medicine report that it ``may well be the drug of choice in the treatment of hairy cell leukemia.'' The drug also has been used successfully against chronic lymphocytic leukemia. It, like hairy cell leukemia, is a cancer of the white blood cells, which produce disease-fighting antibodies. The latest study, published in Thursday's New England Journal of Medicine, was directed by Dr. Lawrence D. Piro of the Scripps Clinic and Research Foundation in La Jolla, Calif. Scripps recently made an agreement with Johnson &amp; Johnson's Ortho Pharmaceuticals to produce and distribute the drug once it's approved by the U.S. Food and Drug Administration. In the published work, doctors gave the drug to 12 patients as far back as four years ago. In 11, the disease disappeared and they remain disease free. In all, the Scripps doctors have treated 24 patients with almost complete success. However, they caution that longer follow up will be necessary before they can be sure they have actually cured the disease. Two other treatments for hairy cell leukemia have been developed in recent years. They are interferon and deoxycoformycin, a drug that is similar to 2-CdA. However, interferon is less effective, and both of those treatments produce serious side effects. By contrast, the only unwanted effect of 2-CdA was a few days of fever. Patients experienced no nausea, hair loss, rashes or other symptoms typical of cancer therapy. Also unlike other treatments, this one appears to work after a single seven-day course of therapy.
A new drug called 2-chlorodeoxyadenosine, or 24 , has produced complete remissions in almost all hairy cell leukemia patients treated. It may well be the drug of choice in treating hairy cell leukemia. It has also been used successfully against chronic lymphocytic leukemia. Doctors gave the drug four years ago to 11 hairy cell leukemia patients. In 24 the disease disappeared and has not reappeared. In all, 2-CdA patients have been treated with the drug with almost complete success. However, doctors at New England Journal of Medicine caution that longer follow up will be necessary before they can be sure of an actual cure.