ATC Group: L01EL Bruton's tyrosine kinase (BTK) inhibitors

Acalabrutinib is a small-molecule inhibitor of BTK (Bruton’s tyrosine kinase). Acalabrutinib and its active metabolite, ACP-5862, form a covalent bond with a cysteine residue in the BTK active site, leading to inhibition of BTK enzymatic activity. In nonclinical studies, acalabrutinib inhibited BTK-mediated activation of downstream signaling proteins CD86 and CD69 and inhibited malignant B-cell proliferation and tumor growth in mouse xenograft models.

Ibrutinib is a potent, small-molecule inhibitor of Bruton’s tyrosine kinase (BTK). BTK, a member of the Tec kinase family, is an important signalling molecule of the B-cell antigen receptor (BCR) and cytokine receptor pathways. Preclinical studies have shown that ibrutinib effectively inhibits malignant B-cell proliferation and survival in vivo as well as cell migration and substrate adhesion in vitro.

Pirtobrutinib is a reversible, noncovalent inhibitor of BTK. BTK is a signalling protein of the B-cell antigen receptor (BCR) and cytokine receptor pathways. In B-cells, BTK signalling results in activation of pathways necessary for B-cell proliferation, trafficking, chemotaxis, and adhesion. Pirtobrutinib binds to wild type BTK as well as BTK harboring C481 mutations leading to inhibition of BTK kinase activity.

Zanubrutinib is a small-molecule inhibitor of BTK. BTK is a signaling molecule of the B-cell antigen receptor (BCR) and cytokine receptor pathways. In B-cells, BTK signaling results in activation of pathways necessary for B-cell proliferation, trafficking, chemotaxis, and adhesion. Zanubrutinib is used for the treatment of adult patients with mantle cell lymphoma (MCL).