Targeting Bruton's Tyrosine Kinase in CLL

Area of Science:

• Oncology
• Pharmacology
• Immunology

Background:

• Bruton's tyrosine kinase (BTK) inhibitors have revolutionized B-cell lymphoma treatment, particularly chronic lymphocytic leukemia (CLL).
• Covalent BTK inhibitors (BTKis) show significant efficacy in high-risk CLL subgroups, including those with TP53 aberrations and unmutated IGHV.
• Approved BTKis include ibrutinib, acalabrutinib, and zanubrutinib, with varying indications and target selectivity.

Purpose of the Study:

• To review the efficacy and challenges of BTK inhibitors in B-cell malignancies.
• To discuss the mechanisms of resistance to covalent BTKis.
• To explore potential future therapeutic strategies for BTKi-resistant disease.

Main Methods:

• Literature review of clinical trials and research studies on BTK inhibitors.
• Analysis of mechanisms driving disease progression on BTK inhibitors.
• Discussion of emerging therapeutic approaches.

Main Results:

• Covalent BTKis have demonstrated significant clinical benefits in CLL and other B-cell lymphomas.
• Disease progression can occur due to histologic transformation or the emergence of BTK/PLCG2 mutated CLL clones.
• Differences in target selectivity among BTKis contribute to varying adverse effect profiles.

Conclusions:

• While BTK inhibitors offer substantial benefits, resistance remains a critical clinical challenge.
• Fixed-duration combination regimens and reversible BTK inhibitors show promise for overcoming resistance.
• Further research is needed to optimize treatment strategies and manage BTKi-resistant B-cell malignancies.