Pirtobrutinib, or LOXO-305 and LY 3527727, is a Bruton's tyrosine kinase (BTK) inhibitor and antineoplastic agent. Pirtobrutinib showed promising initial efficacy in pts with pretreated Richter transformation with extremely poor prognosis, including in patients who had received prior chemoimmunotherapy and covalent BTK inhibitors. Pirtobrutinib is a highly selective and potent non-covalent BTK inhibitor (BTKi) with high oral bioavailability and a long half-life, resulting in robust BTK target coverage even in high-grade malignancies with high BTK protein turnover.
