scholarly journals Current and Emerging Drug Therapies in Chronic Lymphocytic Leukemia

2017 ◽  
Vol 13 (01) ◽  
pp. 34
Author(s):  
Tarsheen K Sethi ◽  
Nishitha M Reddy ◽  
◽  

Until recently, chemoimmunotherapy has been the mainstay of treatment approach in chronic lymphocytic leukemia (CLL) patients requiring intervention. With the emergence of targeted treatments, there has been a shift in CLL therapy. With a better understanding of disease biology and risk stratification, a tailored approach based on patient age and comorbidities has evolved over time. The development of new and potent, next generation CD20 antibodies has refined therapy options especially for elderly unfit patients. Furthermore, agents targeting important pathways involved in proliferation and survival of CLL cells including B-cell receptor (BCR) signaling have provided additional treatment options in traditionally chemo-refractory CLL. Given the rapidly expanding repertoire of drugs, current research is focused on optimizing treatment sequence, duration of treatment and assessing long-term toxicities. Several immune mediated therapies are emerging and new combinations are being tested to re-establish antitumor immune effector response in CLL. While embracing the advances in CLL therapy, a few longstanding lessons remain. There is still little role of treatment of asymptomatic individuals. This review presents an overview of current and emerging drug therapies in the rapidly changing area of CLL treatment.

Blood ◽  
2021 ◽  
Author(s):  
Thomas E Lew ◽  
Constantine S. Tam ◽  
John F. Seymour

Venetoclax-based regimens have expanded the therapeutic options for patients with chronic lymphocytic leukemia (CLL), frequently achieving remissions with undetectable measurable residual disease (uMRD) and facilitating time-limited treatment without utilizing chemotherapy. Although response rates are high and durable disease control is common, longer-term follow-up of patients with relapsed and refractory (RR) disease, especially in the presence of TP53 aberrations, demonstrates frequent disease resistance and progression. Although the understanding of venetoclax resistance remains incomplete, progressive disease (PD) is typified by oligoclonal leukemic populations with distinct resistance mechanisms, including BCL2 mutations, upregulation of alternative BCL2 family proteins and genomic instability. Although most commonly observed in heavily pre-treated patients with disease refractory to fludarabine and harboring complex karyotype (CK), Richter transformation (RT) presents a distinct and challenging manifestation of venetoclax resistance. For patients with progressive CLL after venetoclax, treatment options include B-cell receptor pathway inhibitors (BCRis), allogeneic stem cell transplantation (SCT), chimeric antigen receptor (CAR) T-cells, and venetoclax re-treatment for those with disease relapsing after time-limited therapy. However, data to inform clinical decisions for these patients are limited. We review the biology of venetoclax resistance and outline an approach to the common clinical scenarios encountered after venetoclax-based therapy that will increasingly confront practising clinicians.


2017 ◽  
Vol 13 (6) ◽  
pp. 371-377 ◽  
Author(s):  
Jennifer Edelmann ◽  
John G. Gribben

Patients with chronic lymphocytic leukemia (CLL) having a chromosomal loss on the short arm of chromosome 17 including the TP53 gene locus (17p deletion) and/or having mutations in TP53 have a short overall survival and, until recently, limited treatment options. The recent introduction of two novel substance classes, B-cell receptor inhibitors and BH3 mimetics, into CLL treatment has provided enormous clinical progress in this previously difficult-to-treat patient subgroup characterized by high risk for treatment failure with standard chemoimmunotherapy and rapid disease progression. Compounds now approved for the treatment of TP53-deficient CLL are the two B-cell receptor inhibitors ibrutinib and idelalisib and the BH3 mimetic venetoclax. All three compounds were approved on the basis of favorable response rates that, importantly, revealed no differences between TP53-competent and TP53-deficient CLL cases. Using these compounds, longer-lasting remissions in patients with TP53-deficient CLL could be demonstrated for the first time. Whether TP53 alterations will maintain their significance as adverse prognostic factors in treatment strategies involving novel compounds needs to be assessed. This review provides an overview of current treatment options for 17p-deleted/ TP53-mutated CLL, including those compounds that are already approved by the US Food and Drug Administration or are under advanced clinical investigation. Available clinical trial data are discussed, as is the use of novel targeted treatment options in the context of transplant strategies, and an algorithm for off-study treatment of 17p-deficient CLL is suggested.


2016 ◽  
Vol 23 (7) ◽  
pp. 502-517 ◽  
Author(s):  
Bernard L Marini ◽  
Lisa Samanas ◽  
Anthony J Perissinotti

Treatment options for chronic lymphocytic leukemia, the most common leukemia in the United States, have expanded rapidly in recent years. While traditional chemoimmunotherapy still remains a mainstay for young, fit patients, a number of novel targeted therapies have emerged that have changed the therapeutic landscape. Two innovative anti-CD20 monoclonal antibodies, obinutuzumab and ofatumomamab, have demonstrated activity in chronic lymphocytic leukemia and represent well-tolerated options in upfront management of elderly patients or in those with significant comorbidities. Agents targeting the B-cell receptor pathway, ibrutinib and idelalisib, have excellent activity in chronic lymphocytic leukemia, particularly in those patients with 17p deletions, in which responses to chemoimmunotherapy are traditionally dismal. Venetoclax (ABT-199), the recently FDA-approved BCL2 inhibitor, as well as several other agents and therapy combinations in the pipeline offer great promise for patients with chronic lymphocytic leukemia, particularly in the relapsed/refractory setting. This article comprehensively reviews the data for novel agents in chronic lymphocytic leukemia, including the pharmacology of therapies, unique toxicities, and other practical management considerations for clinicians.


Blood ◽  
2006 ◽  
Vol 107 (5) ◽  
pp. 2090-2093 ◽  
Author(s):  
Dirk Kienle ◽  
Axel Benner ◽  
Alexander Kröber ◽  
Dirk Winkler ◽  
Daniel Mertens ◽  
...  

The mutation status and usage of specific VH genes such as V3-21 and V1-69 are potentially independent pathogenic and prognostic factors in chronic lymphocytic leukemia (CLL). To investigate the role of antigenic stimulation, we analyzed the expression of genes involved in B-cell receptor (BCR) signaling/activation, cell cycle, and apoptosis control in CLL using these specific VH genes compared to VH mutated (VH-MUT) and VH unmutated (VH-UM) CLL not using these VH genes. V3-21 cases showed characteristic expression differences compared to VH-MUT (up: ZAP70 [or ZAP-70]; down: CCND2, P27) and VH-UM (down: PI3K, CCND2, P27, CDK4, BAX) involving several BCR-related genes. Similarly, there was a marked difference between VH unmutated cases using the V1-69 gene and VH-UM (up: FOS; down: BLNK, SYK, CDK4, TP53). Therefore, usage of specific VH genes appears to have a strong influence on the gene expression pattern pointing to antigen recognition and ongoing BCR stimulation as a pathogenic factor in these CLL subgroups.


Blood ◽  
2006 ◽  
Vol 108 (4) ◽  
pp. 1135-1144 ◽  
Author(s):  
Silvia Deaglio ◽  
Tiziana Vaisitti ◽  
Semra Aydin ◽  
Enza Ferrero ◽  
Fabio Malavasi

Abstract The absence of mutations in the IgV genes, together with the presence of ZAP-70 and CD38, are the most reliable negative prognostic markers for chronic lymphocytic leukemia (CLL) patients. Several lines of evidence indicate that CD38 may be not only a diagnostic marker but also a key element in the pathogenetic network in CLL. First, CD38 is a receptor that induces proliferation and increases survival of CLL cells. Second, CD38 signals start upon interaction with the CD31 ligand expressed by stromal and nurse-like cells. Third, CD38/CD31 contacts up-regulate CD100, a semaphorin involved in sustaining CLL growth. Fourth, evidence that nurselike cells express high levels of CD31 and plexin-B1, the high-affinity ligand for CD100, offers indirect confirmation for this model of receptor cross-talk. Elements of variation in the clinical course of CD38+ CLL patients include (1) potential intersection with ZAP-70, a kinase involved in the CD38 signaling pathway in T and natural killer (NK) cells, and (2) the effects of genetic polymorphisms of the receptors involved, at least of CD38 and CD31. Consequently, CD38 together with ZAP-70 appear to be the key elements of a coreceptor pathway that may sustain the signals mediated by the B-cell receptor and potentially by chemokines and their receptors. This would result in acquisition of increased survival potential, providing clues to the poorer prognosis of CD38+ patients.


Blood ◽  
2008 ◽  
Vol 112 (12) ◽  
pp. 4665-4674 ◽  
Author(s):  
Livio Trentin ◽  
Martina Frasson ◽  
Arianna Donella-Deana ◽  
Federica Frezzato ◽  
Mario A. Pagano ◽  
...  

Abstract Lyn, a tyrosine kinase belonging to the Src family, plays a key role as a switch molecule that couples the B-cell receptor to downstream signaling. In B-CLL cells, Lyn is overexpressed, anomalously present in the cytosol, and displays a high constitutive activity, compared with normal B lymphocytes. The aim of this work was to gain insights into the molecular mechanisms underlying these aberrant properties of Lyn, which have already been demonstrated to be related to defective apoptosis in B-cell chronic lymphocytic leukemia (B-CLL) cells. Herein, Lyn is described to be in an active conformation as integral component of an aberrant cytosolic 600-kDa multiprotein complex in B-CLL cells, associated with several proteins, such as Hsp90 through its catalytic domain, and HS1 and SHP-1L through its SH3 domain. In particular, Hsp90 appears tightly bound to cytosolic Lyn (CL), thus stabilizing the aberrant complex and converting individual transient interactions into stable ones. We also demonstrate that treatment of B-CLL cells with geldanamycin, an Hsp90 inhibitor already reported to induce cell death, is capable of dissociating the CL complex in the early phases of apoptosis and thus inactivating CL itself. These data identify the CL complex as a potential target for therapy in B-CLL.


Author(s):  
Sarah Wilmore ◽  
Karly-Rai Rogers-Broadway ◽  
Joe Taylor ◽  
Elizabeth Lemm ◽  
Rachel Fell ◽  
...  

AbstractSignaling via the B-cell receptor (BCR) is a key driver and therapeutic target in chronic lymphocytic leukemia (CLL). BCR stimulation of CLL cells induces expression of eIF4A, an initiation factor important for translation of multiple oncoproteins, and reduces expression of PDCD4, a natural inhibitor of eIF4A, suggesting that eIF4A may be a critical nexus controlling protein expression downstream of the BCR in these cells. We, therefore, investigated the effect of eIF4A inhibitors (eIF4Ai) on BCR-induced responses. We demonstrated that eIF4Ai (silvestrol and rocaglamide A) reduced anti-IgM-induced global mRNA translation in CLL cells and also inhibited accumulation of MYC and MCL1, key drivers of proliferation and survival, respectively, without effects on upstream signaling responses (ERK1/2 and AKT phosphorylation). Analysis of normal naïve and non-switched memory B cells, likely counterparts of the two main subsets of CLL, demonstrated that basal RNA translation was higher in memory B cells, but was similarly increased and susceptible to eIF4Ai-mediated inhibition in both. We probed the fate of MYC mRNA in eIF4Ai-treated CLL cells and found that eIF4Ai caused a profound accumulation of MYC mRNA in anti-IgM treated cells. This was mediated by MYC mRNA stabilization and was not observed for MCL1 mRNA. Following drug wash-out, MYC mRNA levels declined but without substantial MYC protein accumulation, indicating that stabilized MYC mRNA remained blocked from translation. In conclusion, BCR-induced regulation of eIF4A may be a critical signal-dependent nexus for therapeutic attack in CLL and other B-cell malignancies, especially those dependent on MYC and/or MCL1.


Blood ◽  
2021 ◽  
Author(s):  
Ishwarya Murali ◽  
Siddha Kasar ◽  
Aishath Naeem ◽  
Svitlana Tyekucheva ◽  
Jasneet Kaur Khalsa ◽  
...  

Inhibitors of Bruton's tyrosine kinase (BTKi) and phosphatidylinositol 3-kinase delta (PI3Kδi) that target the B cell receptor (BCR) signaling pathway have revolutionized the treatment of chronic lymphocytic leukemia (CLL). While mutations associated with resistance to BTK inhibitors have been identified, limited data are available on mechanisms of resistance to PI3Kδi. Here we present findings from longitudinal whole-exome sequencing of multiply relapsed CLL patients (Ncases=28) enrolled in PI3Ki trials. The non-responder subgroup was characterized by baseline activating mutations in MAP2K1, BRAF and KRAS in 60% of patients. PI3Kδ inhibition failed to inhibit ERK phosphorylation (pERK) in non-responder CLL cells with and without mutations, while treatment with MEKi rescued ERK inhibition. Overexpression of MAP2K1 mutants in vitro led to increased basal and inducible pERK and resistance to idelalisib. These data demonstrate that MAPK/ERK activation plays a key role in resistance to PI3Kδi in CLL and provide rationale for combination therapy with PI3Kδ and ERK inhibitors.


Blood ◽  
2004 ◽  
Vol 103 (12) ◽  
pp. 4389-4395 ◽  
Author(s):  
Freda K. Stevenson ◽  
Federico Caligaris-Cappio

Abstract The finding that chronic lymphocytic leukemia (CLL) consists of 2 clinical subsets, distinguished by the incidence of somatic mutations in the immunoglobulin (Ig) variable region (V) genes, has clearly linked prognosis to biology. Antigen encounter by the cell of origin is indicated in both subsets by selective but distinct expression of V genes, with evidence for continuing stimulation after transformation. The key to distinctive tumor behavior likely relates to the differential ability of the B-cell receptor (BCR) to respond. Both subsets may be undergoing low-level signaling in vivo, although analysis of blood cells limits knowledge of critical events in the tissue microenvironment. Analysis of signal competence in vitro reveals that unmutated CLL generally continues to respond, whereas mutated CLL is anergized. Differential responsiveness may reflect the increased ability of post-germinal center B cells to be triggered by antigen, leading to long-term anergy. This could minimize cell division in mutated CLL and account for prognostic differences. Unifying features of CLL include low responsiveness, expression of CD25, and production of immunosuppressive cytokines. These properties are reminiscent of regulatory T cells and suggest that the cell of origin of CLL might be a regulatory B cell. Continuing regulatory activity, mediated via autoantigen, could suppress Ig production and lead to disease-associated hypogammaglobulinemia. (Blood. 2004;103:4389-4395)


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