Bosutinib may be a first-line option for patients with chronic phase chronic myeloid leukemia (CML), according to data presented at the 2017 American Society of Clinical Oncology (ASCO) Annual Meeting in Chicago.1
Data from the BFORE study showed significantly higher 12-month major molecular remission (MMR) and complete cytogenetic response (CCyR) with bosutinib (ClinicalTrials.gov Identifier: NCT02130557) compared with imatinib.
Although the responses were higher, they came at a price — higher incidence of gastrointestinal events and transaminase elevations.
BFORE is an ongoing, multinational phase 3 study where 536 patients with chronic phase CML were randomly assigned to receive bosutinib 400 mg daily (268 patients) or imatinib 400 mg daily (268 patients).
MMR at 12 months was significantly higher with bosutinib: 47.2% vs 36.9% with imatinib (P = .02). A similar pattern was seen for CCyR (at 12 months, 77.2% with bosutinib vs 66.4% with imatinib).
Rates of BCR-ABL transcripts less than 10% at 3 months were 75% for bosutinib and 57% for imatinib.
Although this is an initial read-out, cumulative incidence of event-free survival events at 12 months was lower with bosutinib (3.7% vs 6.4% for imatinib).
One patient on bosutinib and 6 on imatinib died during treatment.
Safety data were consistent with what has been reported for bosutinib. Most of the gastrointestinal events were grade 1 to 2 and did not require treatment discontinuation. Higher incidence of grade 3 or worse events with bosutinib included diarrhea (8% vs 1%) and levels of alanine (19% vs 2%) and aspartate (10% vs 2%) transaminase.
“Bosutinib could become a welcome new front-line treatment option for patients with [chronic phase] CML,” Dr Cortes concluded.
- Cortes JE, Gambacorti-Passerini C, Deininger MW, et al. Bosutinib (BOS) versus imatinib (IM) for newly diagnosed chronic myeloid leukemia (CML): initial results from the BFORE trial. J Clin Oncol. 2017;35(suppl; abstr 7002).
This article originally appeared on Cancer Therapy Advisor