Bosutinib

證據等級: L5

預測適應症: 10 個

Bosutinib: From Philadelphia Chromosome-Positive CML to Myeloid Leukemia

One-Sentence Summary

Bosutinib is a second-generation dual BCR-ABL1/Src tyrosine kinase inhibitor with well-established global approval for the treatment of Philadelphia chromosome-positive (Ph+) chronic myeloid leukaemia (CML). The TxGNN model predicts it may be effective for myeloid leukemia broadly, with 50+ clinical trials and 20 publications currently supporting this direction — confirming its pharmacological basis in myeloid malignancies. Although no product is currently listed in the Danish Medicines Agency (Laegemiddelstyrelsen) national database, bosutinib holds a centralised EMA marketing authorisation (Bosulif®, Pfizer) valid across all EU member states, including Denmark.

Quick Overview

Item	Content
Original Indication	Philadelphia chromosome-positive (Ph+) chronic myeloid leukaemia (CML)
Predicted New Indication	Myeloid Leukemia
TxGNN Prediction Score	98.75%
Evidence Level	L1
Denmark Market Status	Not registered in national database; EMA centralised authorisation (EU/1/13/810) applies
Number of Marketing Authorisations	0 (national registry); EMA centralised authorisation covers Denmark as EU member state
Recommended Decision	Go

Why is This Prediction Reasonable?

Bosutinib is a potent, orally administered inhibitor of two key kinase families: BCR-ABL1 and the Src family kinases (SFKs). In CML, the Philadelphia chromosome creates a constitutively active BCR-ABL1 fusion oncogene, which drives uncontrolled proliferation and survival of myeloid progenitor cells. By occupying the ATP-binding pocket of BCR-ABL1, bosutinib blocks this oncogenic signalling cascade and suppresses CML cell growth. Its additional inhibition of Src kinases — which are not targeted by first-generation imatinib — is thought to contribute to broader anti-leukaemic activity and a distinct resistance profile. This dual mechanism explains why bosutinib retains activity in a substantial proportion of patients resistant to imatinib or other BCR-ABL1 inhibitors.

The TxGNN prediction of “myeloid leukemia” is pharmacologically well-grounded, as CML is itself classified within the myeloid leukaemia spectrum. Multiple Phase 3 randomised controlled trials have confirmed bosutinib’s superiority over imatinib in newly diagnosed chronic-phase CML in terms of depth and speed of molecular response (BFORE trial, NCT02130557), and its efficacy as a later-line option in patients who have failed prior TKI therapy (ASCEMBL, NCT03106779). The European LeukemiaNet (ELN) 2020 guidelines explicitly recommend bosutinib as an approved first-line treatment option alongside imatinib, dasatinib, and nilotinib. There is also preliminary evidence from exploratory trials examining bosutinib in acute myeloid leukaemia (AML) combinations, suggesting potential broader myeloid activity.

The high TxGNN score (98.75%) reflects the depth of pharmacological and network-level evidence connecting bosutinib to myeloid leukaemia biology. For Danish healthcare teams, the key clinical question is not whether evidence supports this indication — it clearly does at the highest level — but rather how to access and position bosutinib within the Danish CML treatment pathway, given that the drug does not appear in the national product register despite holding a valid EU-wide authorisation.

Clinical Trial Evidence

Trial Number	Phase	Status	Enrollment	Key Findings
NCT00574873	Phase 3	Completed	502	BELA trial: bosutinib vs imatinib in newly diagnosed chronic-phase Ph+ CML; evaluates complete cytogenetic response at 12 months as primary endpoint
NCT02130557	Phase 3	Completed	536	BFORE trial: bosutinib 400 mg QD vs imatinib in newly diagnosed CP-CML; 5-year follow-up confirmed sustained molecular response benefit
NCT03106779	Phase 3	Completed	233	ASCEMBL: asciminib vs bosutinib in CML-CP after ≥2 prior TKIs; bosutinib served as active comparator arm
NCT04971226	Phase 3	Active, not recruiting	406	Asciminib 80 mg QD vs investigator-selected TKI (including bosutinib 400 mg QD) for newly diagnosed Ph+ CML-CP
NCT03831776	Phase 2	Completed	212	NordCML012: ropeginterferon α-2b plus bosutinib vs bosutinib monotherapy as frontline CML therapy; aims to increase treatment-free remission rates
NCT03205267	Phase 2	Unknown	127	Step-in dosing of bosutinib in CP-CML patients intolerant or refractory to imatinib, nilotinib, or dasatinib; tests whether gradual dose escalation reduces early toxicity
NCT02810990	Phase 2	Completed	65	BEST study: bosutinib efficacy and tolerability in elderly CML patients failing front-line TKI therapy
NCT00261846	Phase 1/2	Completed	571	Pivotal bosutinib phase 1/2 study in Ph+ leukaemias; established maximum tolerated dose and confirmed efficacy across multiple lines of therapy
NCT03128411	Phase 2	Completed	64	Bosutinib monotherapy in Japanese patients with newly diagnosed CP-CML; assesses efficacy and safety in the Asian population
NCT04258943	Phase 1/2	Active, not recruiting	60	ITCC-054/COG-AAML1921: bosutinib in paediatric patients with newly diagnosed or resistant/intolerant Ph+ CML; determines recommended paediatric dose

Literature Evidence

PMID	Year	Type	Journal	Key Findings
29091516	2018	RCT	J Clin Oncol	BFORE trial: bosutinib demonstrated superior major molecular response at 12 months vs imatinib (47.2% vs 36.9%) in newly diagnosed CP-CML
35643868	2022	RCT	Leukemia	BFORE 5-year final results: sustained molecular response benefit confirmed; 59.7% of bosutinib-treated patients remained on study at completion
34407542	2021	RCT	Blood	ASCEMBL phase 3: asciminib showed superior MMR at 24 weeks (25.5% vs 13.2%) vs bosutinib; bosutinib established as standard-of-care comparator in later-line CML
36717654	2023	RCT	Leukemia	ASCEMBL extended follow-up: bosutinib maintained 20.2% MMR at 96 weeks; confirmed as active and clinically relevant third-line option
39164407	2024	Phase 4	Leukemia	BYOND trial final results: 71.8% of Ph+ CP-CML patients achieved complete cytogenetic response with bosutinib after prior TKI failure; median follow-up 47.8 months
32127639	2020	Guidelines	Leukemia	ELN 2020 recommendations: bosutinib endorsed as approved first-line option for CP-CML; guidance on monitoring milestones and response criteria
40094679	2025	Review	JAMA	Comprehensive CML review: bosutinib classified as a standard second-generation TKI; approximately 5 million patients worldwide live with CML and may benefit from TKI therapy
39252937	2024	Review	Front Oncol	Critical review of bosutinib clinical data and expert recommendations covering efficacy across lines of therapy, toxicity profile, and patient selection criteria
39093014	2024	Review	Am J Hematol	CML 2025 update: bosutinib highlighted for favourable cardiovascular safety profile compared with nilotinib and ponatinib; suitable for patients with pre-existing cardiovascular risk
30587215	2018	Review	J Hematol Oncol	Expert panel guidance on managing bosutinib adverse events in CP-CML; diarrhoea and hepatotoxicity are the most clinically relevant, generally manageable with dose adjustment

Denmark Market Information

Bosutinib (Bosulif®, Pfizer) does not currently appear in the Laegemiddelstyrelsen national product register. However, as a centrally authorised medicinal product, the EMA marketing authorisation is directly applicable in Denmark without requiring a separate national approval.

Marketing Authorisation Number	Product Name	Dosage Form	Approved Indication
EU/1/13/810	Bosulif® (Pfizer)	Film-coated tablets (100 mg, 400 mg, 500 mg)	Ph+ CML in chronic, accelerated, and blast phase in adults previously treated with ≥1 TKI; also newly diagnosed Ph+ CP-CML

Prescribers in Denmark should verify the current SmPC and reimbursement status via the EMA product database (medicines.eea.europa.eu) or contact Pfizer Denmark directly regarding commercial availability.

Cytotoxicity

Bosutinib is an antineoplastic targeted therapy. It is not a conventional cytotoxic chemotherapy agent.

Item	Content
Cytotoxicity Classification	Targeted therapy — BCR-ABL1/Src dual kinase inhibitor (2nd-generation TKI); small molecule oral targeted agent
Myelosuppression Risk	Moderate: thrombocytopenia and neutropenia are recognised class effects; generally less severe than with conventional chemotherapy or some other second-generation TKIs
Emetogenicity Classification	Low to moderate (gastrointestinal effects, primarily diarrhoea and nausea, are the dominant adverse event class; distinct from classical chemotherapy-induced emesis)
Monitoring Items	Full blood count (FBC) with differential; liver function tests (ALT, AST, bilirubin); renal function (eGFR/creatinine); BCR-ABL1 transcript level by IS-standardised PCR at defined milestones
Handling Protection	Standard oral antineoplastic handling precautions; gloves required when handling broken or crushed tablets; no special intravenous handling required

Safety Considerations

Full Danish prescribing information (SmPC) is not available within this evidence pack. Based on published clinical trial data and expert consensus:

Gastrointestinal toxicity: Diarrhoea is the most frequently reported adverse event across all bosutinib trials (occurring in the majority of patients), typically appearing early in treatment and manageable through dose reduction, short-term interruption, or antidiarrhoeals — early proactive management is recommended
Hepatotoxicity: Clinically significant elevations in ALT and AST occur and necessitate regular liver function monitoring, particularly during the first three months; dose interruption or reduction is usually effective
Haematological toxicity: Thrombocytopenia and neutropenia occur and may require dose adjustment; haematological monitoring with FBC at regular intervals is essential
Drug interaction — warfarin: A clinically relevant pharmacodynamic interaction between bosutinib and warfarin has been reported (PMID 24359239); close INR monitoring and anticoagulation management are advised if co-prescribed

Please refer to the approved EMA Summary of Product Characteristics (SmPC) for complete prescribing information: Bosulif SmPC — EMA

Conclusion and Next Steps

Decision: Go

Rationale: The TxGNN prediction for bosutinib in myeloid leukaemia is supported by the highest available evidence level (L1: multiple completed Phase 3 RCTs, ELN guideline endorsement, and EMA centralised marketing authorisation). This is a well-characterised, globally established therapy with no regulatory barrier to use in Denmark.

To proceed, the following is needed:

Confirm commercial availability and reimbursement pathway through Laegemiddelstyrelsen and the Danish Regions’ joint medicine procurement system (Amgros)
Obtain and review the current EMA SmPC to ensure prescribers are familiar with the approved indication scope, monitoring requirements, and dose modification guidelines
Verify institutional capacity for BCR-ABL1 molecular monitoring (IS-standardised PCR), which is required for treatment response assessment and discontinuation decisions
Position bosutinib within the local CML treatment algorithm relative to available alternatives (imatinib, dasatinib, nilotinib, asciminib), taking into account bosutinib’s particularly favourable cardiovascular safety profile — relevant for Danish CML patients with pre-existing metabolic or vascular comorbidities
Establish a structured haematological and hepatic monitoring programme aligned with ELN 2020 recommendations before initiating the first patient

Disclaimer: This report is intended for research reference purposes only and does not constitute medical advice. Drug repurposing candidates require clinical validation before therapeutic application. Data cutoff: 2026-04-04.

Disclaimer

This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.