Making cancer remission a reality
A new drug designed using an innovative technique called molecular modeling --2-chlorodeoxyadenosine--is long on syllables but succinct in its effectiveness. A recent study shows it may trounce a rare form of cancer in only one treatment.
The cancer is known as hairy-cell leukemia. It causes smooth infection-fighting white blood cells in the bone marrow to be replaced with abnormal cells sprouting hairlike projections. It is often fatal.
In the study, 12 patients admitted to the Scripps Clinic in California, were given week-long infusions of very small amounts of the new drug. Eleven had complete remissions, meaning total disappearance of the disease. At present, the average remission continues at 18 months, with one patient going on four years leukemia-free. None of the patients have had relapses (New England Journal of Medicine, April 19, 1990).
"The response so far has been promising. Very rarely do you hear of long-lasting cancer remissions following one treatment," says Lawrence D. Piro, M.D., head of the division of hematology and director of the Green Cancer Center at Scripps Clinic. "And with the patient exposed to only one treatment at an extremely low dose, the chances for complications should be low."
With some chemotherapy drugs, side effects can be rough--nausea, vomiting, hair loss, kidney and liver damage. Not here. "In the doses used in the study, this drug appears to have no toxicity in any other organ. It seems to affect only the bone marrow, where the cancer resides," says Dr. Piro. Unlike some other drugs used to fight hairy-cell leukemia, this one does not appear to weaken the immune system either.
Even though hairy-cell leukemia is a rare disease (affecting about 6,000 people nationwide) the success of this "designer" drug offers hope for fighting other diseases. "Many chemotherapy drugs are derived from plants and bacteria, but this drug is the product of a technique called molecular modeling, in which scientists design a drug to have an intended effect. We may be able to design other drugs using the same concept that are just as effective and low in toxicity for other illnesses," says Dr. Piro.
The treatment is currently available only at Scripps Clinic and at the M.D. Anderson Cancer Center, Houston, with a total of 55 patients with the disease having received it so far. But it is expected to be more widely available soon.
By Greg Gutfeld with Melissa Meyers & Maureen Sangiorgio