ibrutinib or acalabrutinib

This entry is **non-specific**: it refers disjunctively to either **ibrutinib** or **acalabrutinib**, two distinct oral covalent small-molecule inhibitors of Bruton's tyrosine kinase. Both suppress B-cell receptor signaling and are used in B-cell malignancies, but they are separate chemical entities with different development codes, sponsors, selectivity profiles, formulations, regulatory indications, dosing schedules, and safety characteristics. Ibrutinib is marketed as Imbruvica, while acalabrutinib is marketed as Calquence; they must be represented as separate drug records rather than as a combination product or a single canonical drug.