Ibrutinib in B-cell Lymphomas

Kami Maddocks, Kristie A. Blum

The standard frontline therapy for diffuse large B-cell lymphoma (DLBCL), follicular lymphoma (FL), and mantle cell lymphoma (MCL) includes the use of chemoimmunotherapy and/or radiation therapy. When patients with these diseases relapse or are refractory to therapy, their diseases are considered incurable outside of the setting of an autologous or allogeneic stem cell transplant, which many patients are not candidates for due to age or comorbidities. The oral Bruton's tyrosine kinase (BTK) inhibitor, ibrutinib, targets the B-cell receptor (BCR) signaling pathway that is critical in the survival of these malignancies. It has shown promising activity in certain subtypes of DLBCL, in relapsed or refractory FL, and in relapsed or refractory MCL for which it has recently received FDA approval and should be considered for use in patients in first relapse. Ibrutinib is an oral therapy taken daily that has been well tolerated by patients. Given the high response rates, tolerability, and acceptable toxicities of ibrutinib therapy, it is now being evaluated in combination therapy both in relapsed B-cell malignancies and frontline studies in DLBCL and MCL. Several other promising agents targeting different kinases in the BCR signaling pathway also are currently under investigation.