FDA Grants Accelerated Approval to Bosutinib for Treatment of Newly Diagnosed Philadelphia Chromosome–Positive CML

On December 19, 2017, the U.S. Food and Drug Administration (FDA) granted accelerated approval to bosutinib (Bosulif) for treatment of patients with newly diagnosed chronic-phase Philadelphia chromosome–positive chronic myelogenous leukemia (CML).


Approval was based on data from an open-label, randomized, multicenter BFORE trial in 487 patients with Philadelphia chromosome–positive newly diagnosed chronic phase CML who were randomized to receive either bosutinib 400 mg once daily or imatinib (Gleevec) 400 mg once daily. The major efficacy outcome measure was major molecular response (MMR) at 12 months, defined as ≤ 0.1% BCR-ABL ratio on international scale (corresponding to ≥ 3 log reduction from standardized baseline) with a minimum of 3000 ABL transcripts as assessed by the central laboratory.

MMR at 12 months was 47.2% (95% confidence interval [CI] = 40.9–53.4) in the bosutinib arm and 36.9% (95% CI = 30.8–43.0) in the imatinib arm (P = .0200).

Most common adverse reactions in patients with newly diagnosed CML (incidence ≥ 20%) are diarrhea, nausea, thrombocytopenia, rash, increased alanine aminotransferase, abdominal pain, and increased aspartate aminotransferase.

The FDA first approved bosutinib in 2012 for treatment of patients with chronic-, accelerated-, or blast-phase Philadelphia chromosome–positive CML with resistance or intolerance to prior therapy.

The recommended dose of bosutinib for newly diagnosed chronic-phase Philadelphia chromosome–positive CML is 400 mg orally once daily with food.

Full prescribing information is available at: https://www.accessdata.fda.gov/drugsatfda_docs/label/2012/203341lbl.pdf

The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.