New leukemia drugs show early promise

[Guest guest]

New leukemia drugs show early promise

By Gene Emery

BOSTON (Reuters) - Two new drugs may help treat some adult cases of

leukemia that fail to respond to Novartis AG's Gleevec, two studies

showed on Wednesday.

One drug, dasatinib, an experimental Bristol-Myers Squibb Co. drug

recently endorsed by a Food & Drug Administration advisory panel,

could receive full approval by the end of June.

Dasatinib helped 68 out of 84 volunteers suffering from a form of

chronic myeloid leukemia, or CML, that was resistant to Novartis's

Gleevec, according one study led by Sawyers of the University

of California in Los Angeles.

Using genetic testing, the Sawyers team also predicted which patients

would respond to the drug, also known as Sprycel, said the study

published in The New England Journal of Medicine.

The second study, also published in the Journal, evaluated nilotinib,

which Novartis is trying to put on a fast track for approval in the

United States.

Europe has already given nilotinib orphan drug status -- a designation

for drugs developed for rare illnesses where there is no strong profit

motive to make the drugs. CML is relatively rare, striking about 4,600

people a year in the United States.

The study found that 11 of 12 volunteers who received the drug in the

long-term chronic stage of the disease had cancer cells disappear from

the blood. This is positive but does not necessarily mean they were

cured since cancer cells can lurk elsewhere in the body.

In the " blast " stage, which is the most aggressive phase of CML,

cancer cells also disappeared from the blood of 13 out of 33 patients.

For the less-aggressive " accelerated " phase, 33 of 46 responded.

" With it, I believe we are going to make another quantum leap in the

treatment of CML, " said author Hagop Kantarjian of the University of

Texas M.D. Cancer Center, referring to nilotinib.

Nilotinib is designed to be 50 times more potent than Gleevec but it

seems to spark some worrisome abnormal electrical activity in the

heart, the study said.

Further tests are also needed because neither drug was given a

head-to-head comparison with other treatment.

The studies " provide immediate hope for patients in whom CML cells

have developed resistance, " said Druker of the Oregon Health and

Science University Cancer Institute in Portland, in a Journal editorial.

The Sawyers team said successful long-term treatment of CML might

require a combination of such drugs, just as the

AIDS virus is best battled with several medicines given concurrently.