Abstract
Bruton tyrosine kinase inhibitors (BTKis) are an established standard of care in chronic lymphocytic leukemia. The covalent BTKis ibrutinib, acalabrutinib, and zanubrutinib bind to BTK C481 and are all susceptible to the C481S mutation. Noncovalent BTKi, including pirtobrutinib, overcome C481S resistance but are associated with multiple variant (non-C481) BTK mutations, including those associated with resistance to acalabrutinib and zanubrutinib (T474 codon and L528W mutations). We review the current knowledge on variant BTK mutations, discuss their clinical implications, and consider their impact on clinical trials.
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.© 2025 American Society of Hematology. Published by Elsevier Inc. All rights are reserved, including those for text and data mining, AI training, and similar technologies.
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