Comparison of intensive, pediatric-inspired therapy with non-intensive therapy in older adults aged 55-65 years with Philadelphia chromosome-negative acute lymphoblastic leukemia

Novel PIKfyve/Tubulin Dual-target Inhibitor as a Promising Therapeutic Strategy for B-cell Acute Lymphoblastic Leukemia

OBJECTIVE

In B-cell acute lymphoblastic leukemia (B-ALL), current intensive chemotherapies for adult patients fail to achieve durable responses in more than 50% of cases, underscoring the urgent need for new therapeutic regimens for this patient population. The present study aimed to determine whether HZX-02-059, a novel dual-target inhibitor targeting both phosphatidylinositol-3-phosphate 5-kinase (PIKfyve) and tubulin, is lethal to B-ALL cells and is a potential therapeutic for B-ALL patients.

METHODS

Cell proliferation, vacuolization, apoptosis, cell cycle, and in-vivo tumor growth were evaluated. In addition, Genome-wide RNA-sequencing studies were conducted to elucidate the mechanisms of action underlying the anti-leukemia activity of HZX-02-059 in B-ALL.

RESULTS

HZX-02-059 was found to inhibit cell proliferation, induce vacuolization, promote apoptosis, block the cell cycle, and reduce in-vivo tumor growth. Downregulation of the p53 pathway and suppression of the phosphoinositide 3-kinase (PI3K)/AKT pathway and the downstream transcription factors c-Myc and NF-κB were responsible for these observations.

CONCLUSION

Overall, these findings suggest that HZX-02-059 is a promising agent for the treatment of B-ALL patients resistant to conventional therapies.

Recent Advances in Managing Acute Lymphoblastic Leukemia

Acute lymphoblastic leukemia (ALL) is characterized by chromosomal translocations and somatic mutations that lead to leukemogenesis. The incorporation of pediatric-type regimens has improved survival in young adults, and the incorporation of tyrosine kinase inhibitors for patients with Philadelphia chromosome-positive disease has led to further improvements in outcomes. However, older patients often have poor-risk biology and reduced tolerance to chemotherapy, leading to lower remission rates and overall survival. Regardless of age, patients with relapsed or refractory ALL have extremely poor outcomes. The advent of next-generation sequencing has facilitated the revolution in understanding the genetics of ALL. New genetic risk stratification together with the ability to measure minimal residual disease, leukemic blasts left behind after cytotoxic chemotherapy, has led to better tools to guide postremission approaches-that is, consolidation chemotherapy or allogeneic stem cell transplantation. In this article, we discuss the evolving and complex genetic landscape of ALL and the emerging therapeutic options for patients with relapsed/refractory ALL and older patients with ALL.

New approaches to the treatment of older adults with acute lymphoblastic leukemia

Outcomes for older adults (defined here as ≥55-65 years old) with acute lymphoblastic leukemia (ALL) are poor, with long-term survival less than 20%. Pediatric chemotherapy regimens produce long-term cure rates of 80% to 90% in children and 60% to 70% in adolescents and young adults with Ph-negative ALL, however, tolerability of intensive chemotherapy becomes problematic with advanced age due to comorbidities and reduced tolerability of chemotherapy leading to high rates of treatment-related mortality. For older adults with Ph-positive ALL, BCR-ABL1-directed tyrosine kinase inhibitors in combination with corticosteroids or chemotherapy produce deep remissions with low treatment-related toxicity but optimal postremission therapy is not known. New therapeutic approaches for older adults with ALL involve integration of the novel targeted agents including monoclonal antibody-based therapy with blinatumomab and inotuzumab ozogamicin in the frontline. Ongoing studies will ideally define optimal combinations and sequencing of novel agents with or without chemotherapy, tyrosine kinase inhibitors, and/or corticosteroids to maximize efficacy while avoiding treatment-related death. Anti-CD19 chimeric antigen receptor modified T cells are a promising modality, with high rates of remission and minimal residual disease negativity achieved in early phase trials for adults with relapsed/refractory B-cell ALL but the tolerability of chimeric antigen receptor modified T cell therapies in older adults is yet to be well defined. Advances in minimal residual disease detection have helped to effectively stratify adults in complete response in terms of relapse risk and predicted relative benefit for allogeneic hematopoietic cell transplant. For older adults with ALL in complete response at high risk for relapse for whom myeloablative conditioning is predicted to result in excessive transplant-related mortality, reduced-intensity conditioning allogeneic hematopoietic cell transplant is a less toxic approach for providing a graft-versus-leukemia effect and long-term disease control.

Survival in adult acute lymphoblastic leukaemia (ALL): A report from the Swedish ALL Registry

OBJECTIVES

As new, effective therapies emerge for acute lymphoblastic leukaemia (ALL), the results of clinical trials need to relate to standard of care.

METHODS

We used the population-based Swedish ALL Registry to evaluate characteristics, treatment and long-term outcome in 933 patients with diagnosis between 1997 and 2015.

RESULTS

The median age was 53 years. The frequency of Philadelphia (Ph)-positive leukaemia was 34% of examined B-ALL with a peak incidence at 50-59 years. Five-year overall survival (OS) improved between 1997-2006 and 2007-2015; in patients 18-45 years from 50% (95% CI 43-57) to 65% (95% CI 58-72), 46-65 years from 25% (95% CI 18-32) to 46% (95% CI 37-55) and >65 years from 7% (95% CI 2.6-11) to 11% (95% CI 5.9-16) (P < 0.05). Men with Ph-neg B-ALL 46-65 years had inferior OS compared with women (P < 0.01). Standardised mortality ratio was 5.7 (95% CI 5.0-6.3) for patients who survived 5 years from diagnosis. In multivariable analysis, Ph-positive disease was not associated with impaired prognosis but with lower risk of death in 2007-2015.

CONCLUSIONS

In a population-based cohort, OS has improved in adult ALL, especially for Ph-positive disease but for middle-aged men with Ph-negative B-ALL outcome was poor. Cure without late toxicity or relapse is still desired.

Acute Lymphoblastic Leukemia in the Older Adult

Acute lymphoblastic leukemia (ALL) in older adults presents a real challenge as a result of adverse disease biology and comorbidities that preclude delivering curative regimens. Conventional chemotherapy approaches have generally yielded unsatisfactory results in older patients with ALL as a result of excessive induction mortality, chemotherapy resistance of the leukemia, and the need to omit or dose reduce key drugs during the course of therapy because of adverse effects. Philadelphia chromosome–positive ALL represents about a quarter of newly diagnosed older adults, and the striking single-agent activity and excellent safety profile of tyrosine kinase inhibitors has allowed incorporation of these agents into therapy, significantly improving the outcome of older adults with Philadelphia chromosome–positive ALL. Allogeneic hematopoietic cell transplantation using reduced-intensity conditioning is a potentially curative approach in the older adult with ALL, and ironically, it may be better tolerated than intensive combination chemotherapy in a subset of older patients with ALL. Immunotherapies such as chimeric antigen receptor–modified T-cells, the bispecific T-cell–engaging antibody targeting CD19 (blinatumomab), and the antibody-drug conjugate targeting CD22 (inotuzumab) have shown safety and exceptional activity even in advanced ALL, and the efficacy of these agents has been observed irrespective of patient age. Several promising studies tailored specifically toward older adults with ALL are ongoing, with the majority of them incorporating novel immunotherapies, targeted therapies, or third-generation tyrosine kinase inhibitors into the front-line treatment regimen.

P-glycoprotein Activity Correlates With Treatment Response in 2 Leukemia Child Patients

Acute lymphoblastic leukemia is the most important childhood cancer. Multidrug resistance is an important factor of poor prognosis. We present the P-glycoprotein (P-gp) activity in 2 patients with different outcomes. Both patients had B-cell acute lymphoblastic leukemia; they were responding properly to the treatment, but one of them had an increment in the P-gp activity that correlates with an increment in the disease manifestation, the patient had to be hospitalized and developed sepsis and subsequently died. P-gp levels were correlated with disease progression. P-gp activity needs to be evaluated during treatment to assess and prevent disease relapse or the patient´s death.