On Feb. 1, 2002, the U.S. Food and Drug Administration (FDA) approved the drug Gleevec, formerly known as STI571, for treatment of gastrointestinal stromal tumors. The tumors are among the most deadly of intestinal cancers, as there was no other effective treatment besides early surgical removal to date. The confirmatory, phase III study that led to the approval showed that patients taking imatinib for 36 months had a 5-year overall survival of 92%, compared with 82% for those who only took the drug for the standard 12 months of treatment.

Imatinib was first approved in 2001 for the treatment of chronic myeloid leukemia for Philadelphia chromosome–positive patients. In 2002, imatinib was granted approval for the treatment of advanced or metastatic GIST. The accelerated approval for adjuvant use in patients with resectable GIST was granted in 2008.

Gleevec, manufactured by Novartis, was approved by the FDA for chronic- and acute-phase CML treatment in May 2001. Chronic myelogenous leukemia (also called CML or chronic granulocytic leukemia) is a slowly progressing blood and bone marrow disease that usually occurs during or after middle age, and rarely occurs in children.