The oral tyrosine kinase inhibitor bosutinib received expanded approval from the U.S. Food and Drug Administration (FDA) to treat adults with newly diagnosed Philadelphia chromosome-positive (Ph+) chronic-phase (CP) chronic myeloid leukemia (CML).
The decision was based on results of the multinational, open-label, randomized, phase III BFORE (Bosutinib trial in the First Line Chronic Myelogenous Leukemia Treatment) study, which included 536 patients with Ph+ CP-CML who were randomized 1:1 to receive bosutinib 400 mg or imatinib 400 mg.
At 12 months, a higher percentage of patients receiving bosutinib achieved major molecular response (47.2% vs. 36.9%; p=0.02). People treated with bosutinib also had a significantly higher rate of complete cytogenic response at 12 months (77.2% vs. 66.4%; p=0.008).
The most common adverse events (AEs) associated with bosutinib included diarrhea (70%), nausea (35%), thrombocytopenia (35%), rash (34%), increased alanine aminotransferase (31%), abdominal pain (25%), and increased aspartate aminotransferase (23%).
Bosutinib previously received FDA approval for adults with Ph+ CML who were resistant or intolerant to prior therapy.
Source: Pfizer press release, December 19, 2017.