Current diagnosis and treatment of chronic lymphocytic leukaemia

Abstract

Two major advances were made in the treatment of chronic lymphocytic leukaemia (CLL): the addition of the antibody rituximab to chemotherapy two decades ago and the introduction of the targeted agents during the last few years. Four targeted drugs with different mechanisms of action were added to the armamentarium of CLL treatment: the anti-CD20 antibody obinutuzumab, the two kinase inhibitors ibrutinib and idelalisib, which target the Bruton tyrosine kinase (BTK) and Phosphatidylinositiol-3-Kinase (PI3K) respectively in the B-cell receptor signalling pathway, as well as the Bcl2-antagonist venetoclax.Recently, the combination of venetoclax/obinutuzumab was approved for the first-line treatment of all CLL patients based on a phase-III trial in elderly unfit patients. This combination was shown to be clearly superior to chlorambucil/obinutuzumab and should become the preferred first-line treatment for the so called "slow-go" patients. Other options for these elderly, unfit patients are continuous ibrutinib or chlorambucil/obinutuzumab. Although data from phase-III studies are not yet available, venetoclax/obintuzumab may also be offered to younger, fit patients. Established therapeutic options for these so called "go go" patients are ibrutinib, fludarabin/cyclophosphamide/rituximab or bendemustine/rituximab (if > 65 years). Patients with the high-risk parameters deletion 17p or TP53mutation are known to poorly respond to chemo(immuno)therapy and should receive either ibrutinib or venetoclax/obinutuzumab.Thus, a choice has to be made between a continuous monotherapy with ibrutinib or a time-limited combination with either venetoclax/obinutuzumab (12 months) or chemoimmunotherapy (usually 6 months). In addition to disease-related factors (e. g. presence of deletion 17p/TP53 mutation, IgHV mutational status, prior therapies), comorbidities, co-medication and the specific side effects of the CLL therapies (myelosuppression, infections and secondary malignancies for chemoimmunotherapy; cardiac toxicity, bleeding and autoimmune disease for ibrutinib; tumour-lysis syndromes and infections for venetoclax) the patient's expectations need to be considered.