The US Food and Drug Administration (FDA) approved a new indication for imatinib (Gleevec; Novartis) for the treatment of children with newly diagnosed Philadelphia chromosome–positive (Ph+) acute lymphoblastic leukemia (ALL), the most common type of pediatric cancer.
Approximately 2900 children are diagnosed with Ph+ ALL annually in the United States. Imatinib, a tyrosine kinase inhibitor, should be used in combination with chemotherapy for the treatment of children with Ph+ ALL.
Imatinib’s safety and effectiveness in children were established in a clinical trial conducted by the Children’s Oncology Group and sponsored by the National Cancer Institute. The trial included 92 children with a very high risk of Ph+ ALL who were divided into 5 treatment groups; each successive group received a longer period of treatment with imatinib plus chemotherapy. The longest duration of treatment was 4 years.
The mortality rate was lower in parallel with increasing time of treatment with the combination therapy. The lowest mortality rate was seen in the group that received the combination therapy for 4 years: of the 50 patients who received imatinib for 4 years, 70% had event-free survival for that length of time.
The most common side effects reported in the children in this trial included decreased levels of infection-fighting neutrophils, decreased levels of platelets, liver toxicity, and infection. Imatinib is already approved by the FDA for several indications in patients with various types of Ph+ chronic myeloid leukemia. (January 25, 2013)
