Ibrutinib (Imbruvica™) is an irreversible, potent inhibitor of Bruton's tyrosine kinase (BTK). Over the last few years, ibrutinib has developed from a promising drug candidate to being approved by ...FDA for the treatment of three B cell malignancies, a truly remarkable feat. Few, if any medicines are monospecific and ibrutinib is no exception; already during ibrutinib's initial characterization, it was found that it could bind also to other kinases. In this review, we discuss the implications of such interactions, which go beyond the selective effect on BTK in B cell malignancies. In certain cases, the outcome of ibrutinib treatment likely results from the combined inhibition of BTK and other kinases, causing additive or synergistic, effects. Conversely, there are also examples when the clinical outcome seems unrelated to inhibition of BTK. Thus, more specifically, adverse effects such as enhanced bleeding or arrhythmias could potentially be explained by different interactions. We also predict that during long‐term treatment bone homoeostasis might be affected due to the inhibition of osteoclasts. Moreover, the binding of ibrutinib to molecular targets other than BTK or effects on cells other than B cell‐derived malignancies could be beneficial and result in new indications for clinical applications.
Pharmacological agents that inhibit enzymes of the B‐cell receptor (BCR) pathway are of increasing importance in the treatment of B‐cell malignancies. These include inhibitors of Bruton tyrosine ...kinase (BTK), phosphatidylinositol 3‐kinase (PI3K), splenic tyrosine kinase and protein kinase Cβ. Two agents are already approved in the USA and Europe: ibrutinib, a BTK inhibitor, for the treatment of chronic lymphatic leukaemia (CLL), mantle cell lymphoma (MCL) and Waldenström's macroglobulinemia; and idelalisib, a PI3Kδ inhibitor, for the treatment of CLL and follicular lymphoma. In addition, the role of these drugs in diffuse large B‐cell lymphoma and marginal zone lymphoma is under investigation, as single agents and in combination with chemotherapy. In CLL, both ibrutinib and idelalisib have an established role as first‐line therapy in patients with del(17p), and in MCL, ibrutinib is a standard option for patients relapsing after chemoimmunotherapy. Unexpected toxicities have been encountered when combining these potent new agents with other drugs, including chemotherapy and lenalidomide, and based on this experience the risks and benefits of novel combinations must be evaluated carefully. In this review, we summarize the efficacy and safety results with these inhibitors and discuss novel combinations that are under study and the future role of BCR inhibitors in these disorders.
Content List ‐ Read more articles from the symposium: Targeted therapy in B‐cell malignancies.
To complete the existing treatment guidelines for all tumor types, ESMO organizes consensus conferences to better clarify open issues in each disease. In this setting, a consensus conference on the ...management of lymphoma was held on 18 June 2011 in Lugano, immediately after the end of the 11th International Conference on Malignant Lymphoma.
The consensus conference convened ∼45 experts from all around Europe and selected six lymphoma entities to be addressed; for each of them three to five open questions were to be discussed by the experts. For each question, a recommendation should be given by the panel, supported by the strength of the recommendation based on the level of evidence.
This consensus report focuses on the three most common lymphoproliferative malignancies: diffuse large B-cell lymphoma, follicular lymphoma and chronic lymphocytic leukemia. A second report will concentrate on mantle cell lymphoma, marginal zone lymphoma and T-cell lymphomas.
The role of both autologous (autoSCT) and allogeneic stem cell transplantation (alloSCT) in the management of mantle cell lymphoma (MCL) remains to be clarified. We conducted a consensus project ...using the RAND-modified Delphi consensus procedure to provide guidance on how SCT should be used in MCL. With regard to autoSCT, there was consensus in support of: autoSCT is the standard first-line consolidation therapy; induction therapy should include high-dose cytarabine and Rituximab; complete or partial remission should be achieved before autoSCT; Rituximab maintenance following autoSCT is not indicated; and omission of autoSCT in 'low-risk' patients is not indicated. No consensus could be reached regarding: autoSCT in the treatment of relapsed disease following non-transplant therapy; the value of positron emission tomography scanning and minimal residual disease (MRD) monitoring; in vivo purging with Rituximab; total body irradiation conditioning for autoSCT; and preemptive Rituximab after autoSCT. For alloSCT, consensus was reached in support of: alloSCT should be considered for patients relapsing after autoSCT; reduced intensity conditioning regimens should be used; allogeneic immunotherapy should be used for MRD eradication after alloSCT; and there is a lack of prognostic criteria to guide the use of alloSCT as first-line consolidation. No consensus was reached regarding the role of alloSCT for relapsed disease following non-transplant therapy.
The aim of this project was to define indications for hematopoietic stem cell transplantation in follicular lymphoma in Europe. In the absence of evidence-based data, a RAND-modified Delphi procedure ...was used by an expert panel. After pre-defining statements, these were individually/anonymously scored by each participant using a 9-point scale. Consensus was reached that: 1) high-dose therapy with autologous stem cell rescue is not an appropriate option to consolidate first remission in patients responding to immuno-chemotherapy outside clinical trials; 2) in patients with first chemo-sensitive relapse, high-dose therapy with autologous stem cell rescue is an appropriate option to consolidate remission, especially in patients with a short response after immuno-chemotherapy or with high-risk FLIPI; 3) high-dose therapy with autologous stem cell rescue is also appropriate in second/subsequent chemo-sensitive relapses; 4) allotransplant (preferably a reduced intensity conditioning-allotransplant) should be considered at relapse after high-dose therapy with autologous stem cell rescue. No consensus was reached on the role of high-dose therapy with autologous stem cell rescue in low-risk first relapse, or on when an allotransplant should be preferred over high-dose therapy with autologous stem cell rescue. In the absence of evidence-based data, the consensus method used was a valuable tool to define indications for hematopoietic stem cell transplant in follicular lymphoma.
Treatment for follicular lymphoma (FL) improved with rituximab. In Sweden, first-line rituximab was gradually introduced between 2003 and 2007, with regional differences. The first national ...guidelines for FL were published in November 2007, recommending rituximab in first-line therapy. Using the population-based Swedish Lymphoma Registry, 2641 patients diagnosed with FL from 2000 to 2010 were identified and characterized by year and region of diagnosis, age (median, 65 years), gender (50% men), first-line therapy and clinical risk factors. Overall and relative survivals were estimated by calendar periods (2000-2002, 2003-2007 and 2008-2010) and region of diagnosis. With each period, first-line rituximab use and survival increased. Survival was superior in regions where rituximab was quickly adopted and inferior where slowly adopted. These differences were independent in multivariable analyses. Ten-year relative survival for patients diagnosed 2003-2010 was 92%, 83%, 78% and 64% in the age groups 18-49, 50-59, 60-69 and ⩾70, respectively. With increasing rituximab use, male sex emerged as an adverse factor. Survival improved in all patient categories, particularly in elderly women. The introduction and the establishment of rituximab have led to a nationwide improvement in FL survival. However, rituximab might be inadequately dosed in younger women and men of all ages.
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