NCCN Guidelines Insights: Chronic Myeloid Leukemia, Version 1.2017.

The NCCN Guidelines for Chronic Myeloid Leukemia (CML) provide recommendations for the management of chronic-phase and advanced-phase CML in adult patients. The median age of disease onset is 67 years. However, because CML occurs in all age groups, clinical care teams should be prepared to address issues relating to fertility and pregnancy with patients who are of reproductive age at the time of diagnosis. CML is relatively rare in children and there are no evidence-based recommendations for the management of CML in pediatric population. These NCCN Guidelines Insights discuss special considerations for the management of CML during pregnancy and for the management of CML in the pediatric population.

Intensive chemotherapy vs. hypomethylating agents in older adults with newly diagnosed high-risk acute myeloid leukemia: A single center experience.

Acute myeloid leukemia (AML) in older patients is often associated with biologic and clinical characteristics that predict poor outcomes to cytarabine and anthracycline based induction chemotherapy (IC). The impact of hypomethylating agents (HMA) in the treatment of these high-risk patients is unknown. Here we retrospectively examined the remission rates and survival outcomes of 201 newly diagnosed patients ≥60 years old with therapy-related (t-AML), secondary (s-AML), or AML with myelodysplasia-related changes (AML-MRC). Ninety-eight patients received IC, and 103 received HMA. Patients in the IC cohort were younger than those who received HMA (68 vs. 74 years; p < 0.01) with lower comorbidity burden. Composite complete remission rates (CR) were 39% in IC and 27% in the HMA cohorts (p = 0.10). Overall survival (OS) was not significantly different between the two cohorts (7.59 mos vs. 5.49 mos; HR 0.75 95% CI 0.55-1.02) despite the fact that more patients in the IC cohort (33% versus 5%, p < 0.01) underwent allogeneic stem cell transplant. Patients with t-AML (HR 0.56; 95% CI 0.33-0.97) and complex karyotype without monosomal karyotype (CK + MK-; HR 0.37; 95% CI 0.19-0.75) had better OS following IC. Patients with CK + MK+ (HR 2.00; 95% CI 1.08-3.70) had improved OS following HMA. Our results support the use of HMA as an alternative upfront regimen in older individuals with newly diagnosed high-risk AML based on similar clinical outcomes to IC.

Remission of Severe, Relapsed, and Refractory TTP after Multiple Cycles of Bortezomib.

Acquired thrombotic thrombocytopenic purpura (TTP) is characterized by autoantibodies against a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13 (ADAMTS13). Uncleaved von Willebrand factor (VWF) multimers accumulate and bind to platelets which causes spontaneous microthrombi ultimately causing microangiopathic hemolytic anemia, thrombocytopenia, and end-organ ischemia. Plasma exchange (PEX) with or without steroids constitutes standard first-line therapy with rituximab typically reserved for refractory cases. Therapies beyond rituximab lack strong evidence for routine use. Recently, bortezomib, a proteasome inhibitor used commonly in patients with multiple myeloma, was shown to induce remission in patients with refractory TTP. Here, we report a case of severe, relapsed TTP that was refractory to PEX, steroids, and rituximab that underwent remission following three cycles of bortezomib. We discuss the salient features of our case, the mechanism of action of bortezomib, and the very few other similar reports that exist in the literature. We conclude that bortezomib should be considered for patients with TTP refractory to PEX, steroids, and rituximab due to its efficacy and relatively favorable side effect profile.

Dexrazoxane for cardioprotection in older adults with acute myeloid leukemia.

Anthracyclines constitute the backbone of intensive adult acute myeloid leukemia (AML) therapy. Cardiotoxicity is one of its most serious adverse effects, and its incidence increases with cumulative dose. Dexrazoxane is a cardioprotective agent used in conjunction with anthracycline therapy. There is limited data of its usage in adult AML patients. We report the outcomes of six older adults at high risk of anthracycline-induced cardiotoxicity who received dexrazoxane during induction/re-induction therapy. Five had preserved left-ventricular function while two proceeded onto stem-cell transplantation. Additional investigation of dexrazoxane in adult leukemia therapy is warranted, particularly in older patients at highest risk for cardiovascular mortality.

How we will treat chronic myeloid leukemia in 2016.

Imatinib will become generic in 2016; assuming that its price will decrease precipitously, we expect that the economic forces will change our current practice habits. We reviewed the literature on the current recommendations to treat chronic myeloid leukemia and highlight how we plan to deal with these changes. Specifically, we propose to better characterize patients according to prognostic scores, to allow more attention to those at high risk for disease progression, e.g., 3-month guidelines and BCR/ABL1 message half-time, emphasize compliance by using contemporary technologies, and increase the importance of early monitoring. We hope that our message will open communication between providers, insurance companies and healthcare authorities to offer the best care for our patients.

Blinatumomab: enlisting serial killer T-cells in the war against hematologic malignancies.

INTRODUCTION: The approval of blinatumomab signals the long awaited arrival of immunotherapy for acute lymphoblastic leukemia (ALL). Previous options for relapsed or refractory disease were restricted to cytotoxic chemotherapy with limited efficacy and significant toxicity. Through an innovative mechanism of action, blinatumomab stimulates a polyclonal antitumor T-cell response, yielding unprecedented single agent efficacy in the relapsed/refractory setting. Success comes at the cost of immunological toxicities rarely encountered with previous therapies and challenging administration logistics requiring clinical expertise. AREAS COVERED: All published clinical and preclinical studies using blinatumomab were reviewed in addition to all registered ongoing clinical trials and data published in abstract form. The search was limited to the English language. The pharmacology, clinical efficacy, toxicity profile, and logistical considerations for drug administration are discussed. EXPERT OPINION: Blinatumomab is an exciting addition to the treatment armamentarium for relapsed/refractory ALL, yet several questions remain regarding optimal implementation into the current treatment paradigm. A unique toxicity profile should be weighed against promising benefits in a poor prognosis population. Other emerging therapies, such as chimeric antigen receptor-modified T-cells and inotuzumab ozogamicin, with different side effect profiles and administration schedules, may prove to be more beneficial for specific patient populations.

Pharmacogenetics predictive of response and toxicity in acute lymphoblastic leukemia therapy.

Acute lymphoblastic leukemia (ALL) is a relatively rare disease in adults accounting for no more than 20% of all cases of acute leukemia. By contrast with the pediatric population, in whom significant improvements in long term survival and even cure have been achieved over the last 30years, adult ALL remains a significant challenge. Overall survival in this group remains a relatively poor 20-40%. Modern research has focused on improved pharmacokinetics, novel pharmacogenetics and personalized principles to optimize the efficacy of the treatment while reducing toxicity. Here we review the pharmacogenetics of medications used in the management of patients with ALL, including l-asparaginase, glucocorticoids, 6-mercaptopurine, methotrexate, vincristine and tyrosine kinase inhibitors. Incorporating recent pharmacogenetic data, mainly from pediatric ALL, will provide novel perspective of predicting response and toxicity in both pediatric and adult ALL therapies.

Bosutinib for the Treatment of Philadelphia Chromosome-Positive Leukemias.

INTRODUCTION: Bosutinib is a dual ABL1 and SRC third generation tyrosine kinase inhibitor (TKI) indicated for the treatment of patients with chronic myelogenous leukemia (CML) resistant to or intolerant of other BCR-ABL1 inhibitors. Bosutinib is active against leukemia cells expressing imatinib-resistant BCR-ABL1 mutations. Mechanistically, this agent may also be beneficial for Philadelphia chromosome-positive (Ph+) acute lymphoblastic leukemia (ALL) because in preclinical animal models, SRC accelerates ALL disease development. AREAS COVERED: Here we review the current scientific and medical literature on the role of bosutinib for the treatment of CML. We address the unique therapeutic advantages of this agent, specifically its ability to inhibit mutant BCR-ABL1 kinases conferring resistance to other TKIs and its unique safety profile consisting of mainly manageable self-limited diarrhea, not cardiovascular, side effects. Long-term toxicities reported with dasatinib, nilotinib and ponatinib have not been described with bosutinib. Lastly, we present preclinical data demonstrating that bosutinib inhibits a broader range of tyrosine kinases than any other TKI, including those implicated in acute leukemia. EXPERT OPINION: We propose that future studies should explore the use of bosutinib in Ph+ ALL due to its multi-kinase inhibitory activity and its relatively long-term safety compared to other second and third generation TKIs.

A new model of LMP1-MYC interaction in B cell lymphoma.

Epstein-Barr virus (EBV) is associated with aggressive B cell lymphomas (BCLs). Latent membrane protein 1 (LMP1) of EBV is an oncogenic protein required for EBV B cell transformation. However, LMP1 is a weak oncogene in mice. Mice expressing Myc inserted 5' of the Eµ enhancer (iMyc(Eµ)), mimicking the t(8;14) translocation of endemic Burkitt lymphoma, develop delayed onset BCLs. To investigate potential cooperation between LMP1 and oncogenic MYC, we produced mice expressing the LMP1 signaling domain via a hybrid CD40-LMP1 transgene (mCD40-LMP1), and the dysregulated MYC protein of aggressive EBV+ BCLs. mCD40-LMP1/iMyc(Eµ) mice trended toward earlier BCL onset. BCLs from mCD40-LMP1/iMyc(Eµ) mice expressed LMP1 and were transplantable into immunocompetent recipients. iMyc(Eµ) and mCD40-LMP1/iMyc(Eµ) mice developed BCLs with similar immunophenotypes. LMP1 signaling was intact in BCLs as shown by inducible interleukin-6. Additionally, LMP1 signaling to tumor cells induced the two isoforms of Pim1, a constitutively active prosurvival kinase implicated in lymphomagenesis.

Enhanced virulence mediated by the murine coronavirus, mouse hepatitis virus strain JHM, is associated with a glycine at residue 310 of the spike glycoprotein.

The coronavirus, mouse hepatitis virus strain JHM, causes acute and chronic neurological diseases in rodents. Here we demonstrate that two closely related virus variants, both of which cause acute encephalitis in susceptible strains of mice, cause markedly different diseases if mice are protected with a suboptimal amount of an anti-JHM neutralizing antibody. One strain, JHM.SD, caused acute encephalitis, while infection with JHM.IA resulted in no acute disease. Using recombinant virus technology, we found that the differences between the two viruses mapped to the spike (S) glycoprotein and that the two S proteins differed at four amino acids. By engineering viruses that differed by only one amino acid, we identified a serine-to-glycine change at position 310 of the S protein (S310G) that recapitulated the more neurovirulent phenotype. The increased neurovirulence mediated by the virus encoding glycine at position S310 was not associated with a different tropism within the central nervous system (CNS) but was associated with increased lateral spread in the CNS, leading to significantly higher brain viral titers. In vitro studies revealed that S310G was associated with decreased S1-S2 stability and with enhanced ability to mediate infection of cells lacking the primary receptor for JHM ("receptor-independent spread"). These enhanced fusogenic properties of viruses encoding a glycine at position 310 of the S protein may contribute to spread within the CNS, a tissue in which expression of conventional JHM receptors is low.