When officials at the FDA take just 2 1/2 months to approve a new cancer treatment, you know it's got to be some kind of breakthrough. And indeed the drug called Gleevec, which was given the go-ahead last week in record time, has produced dramatic results in patients with a rare malignancy called chronic myeloid leukemia. It's too early to say just how good Gleevec is. But the drug's success so far makes one thing clear. When designing a safe, effective treatment for a particular cancer, it pays to learn as much as possible about its underlying molecular biology.
Chronic myeloid...