Pirtobrutinib

**Semantic type:** Pharmacologic Substance

**Definition:** An orally available, selective, non-covalent Bruton's tyrosine kinase (BTK) inhibitor with potential antineoplastic activity. Upon oral administration, pirtobrutinib selectively and reversibly binds to BTK. This prevents both the activation of the B-cell antigen receptor (BCR) signaling pathway and BTK-mediated activation of downstream survival pathways, thereby inhibiting the growth of malignant B-cells that overexpress BTK. Reversible binding of LOXO-305 may preserve antitumor activity in the presence of certain acquired resistance mutations, including C481 mutated BTK, and limit toxicity associated with inhibition of other non-BTK kinases. BTK, a member of the Src-related BTK/Tec family of cytoplasmic tyrosine kinases, is overexpressed or mutated in B-cell malignancies; it plays an important role in the development, activation, signaling, proliferation and survival of B-lymphocytes.

**Synonyms:** - 5-Amino-3-(4-((5-fluoro-2-methoxybenzamido)methyl)phenyl)-1-((2S)-1,1,1-trifluoropropan-2-yl)-1h-pyrazole-4-carboxamide - BTK Inhibitor LOXO-305 - Jaypirca - LOXO 305 - LOXO-305 - LOXO305 - LY3527727 - PIRTOBRUTINIB