'Astounding' Leukemia Breakthrough

A promising, experimental pill is now being tested internationally in thousands of patients with an often-fatal form of leukemia. The pill appears remarkably effective in extending life, even in patients with end-stage disease, CBS News Medical Correspondent Elizabeth Kaledin reports.

It's an advance in the war on cancer for which researchers have been waiting for years — a little orange pill known as ST1571 — that is showing what some call "astounding" success in treating leukemia. Results of a study to be released Saturday show the drug in many cases causes complete remission of leukemia, a cancer of the blood cells that is often lethal.

"We will be presenting data on well over a thousand patients. The majority of patients are responding and, even more dramatically, we are seeing large numbers of patients with no evidence of leukemia," said Dr. Brian Druker.

Judy Oren was one of the original study participants. She is thrilled with the drug's apparent effect. "It's meant waking up in the morning and, you know, planning for the day," she said.

But the drug has meant a lot more than that to cancer researchers because of the way it works. Unlike chemotherapy, which kills even healthy cells, ST1571 goes after the specific genetic abnormality that causes the leukemia: a first of its kind in so-called "targeted therapies" showing broad-scale success.

"Where we go from here is to identify what those critical abnormalities are in each and every single cancer and leukemia" and then develop drugs to specifically shut down each cancer and leukemia, Dr. Druker said.

The benefits are: the cancer dies and patients suffer few side effects. In Judy's case the worst problem has been water retention and puffy eyes. Researchers say the results they'll be presenting this weekend are so dramatic they'll apply to the FDA for approval as early as next year.

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