The FDA has granted imatinib mesylate (Gleevec) regular approval for use in adult patients following surgical removal of CD117-positive gastrointestinal stromal tumors (GIST). The new approval also highlights an increase in overall patient survival when the drug is taken for 36 months rather than the standard 12 months of treatment.
Imatinib was originally granted accelerated approval for the treatment of advanced or metastatic GIST in 2002. In 2008, imatinib received a subsequent accelerated approval for adjuvant use that is for the treatment of patients with GIST who had had potentially curative resection of GIST tumors, but who were at increased risk for a recurrence. Regular approval for the metastatic GIST indication was also granted in 2008.
“The development of [imatinib] over the past decade highlights the need to further study drugs after approval to truly characterize their benefits,” said Richard Pazdur, MD, Director of the Office of Hematology and Oncology Products in the FDA’s Center for Drug Evaluation and Research. “Although originally approved in the metastatic disease setting, this subsequent trial has demonstrated that longer use of [imatinib] can prolong patient’s lives in earlier disease settings.”
The label is being updated to include clinical data from a large randomized clinical study comparing 12 to 36 months of imatinib. Treatment with imatinib for 36 months significantly prolonged overall survival and the time a patient lived without the disease recurring, compared to those receiving 12 months of imatinib. At 60 months, 92% of patients who received 36 months of imatinib were alive compared to 82% of patients who received 12 months of imatinib. ■