Abstract

Targeted therapies for chronic lymphocytic leukemia (CLL) include venetoclax, the oral inhibitor of B-cell lymphoma-2, and inhibitors of kinases in the B-cell receptor signaling pathway, like Bruton tyrosine kinase and phosphatidylinositol 3 kinase. Randomized clinical trials clearly demonstrated improved progression-free survival with targeted therapy over chemoimmunotherapy in first-line and treatment of relapsed/refractory CLL. Comparative trials of venetoclax-based vs other targeted therapies have not been conducted. Differentiating features and considerations with targeted therapies include goals of treatment and therapeutic approach as well as side effect and toxicity profiles. With targeted therapy options for first-line and relapsed CLL, it is ever more important to develop sound rationale and strategy for selecting first-line and treatment of relapsed disease and for long-term management of the disease, including therapeutic sequencing. Fixed-duration therapy with a treatment-free remission is a particularly appealing prospect, since it avoids continuous exposure to treatment and potential for toxicity. We discuss rationale and practical application of venetoclax in first-line and treatment of relapsed and refractory CLL. Venetoclax is highly active at achieving deep remission for most treated patients with CLL, including those with high-risk disease such as del(17p) CLL.

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