vosaroxin and Leukemia--Myeloid--Acute

Acute myeloid leukemia (AML) is a relapsed and refractory hematological malignancy with a lower morbidity but higher mortality. In addition to hematopoietic stem cell transplantation, chemotherapy is used as the front-line treatment. However, the diversity of available agents and the inconsistency of outcomes of relevant trials render treatment decision-making tough. Network meta-analysis (NMA) is an efficient statistical framework that makes a comprehensive comparison and provides a valuable clinical reference.. All the potential trials were retrieved from the medical database and screened according to the inclusion and exclusion criteria. The main characteristics of each trial as well as the primary outcomes, including complete remission (CR), overall response rate (ORR), overall survival (OS), and event-free survival (EFS), were extracted. In addition, the network graph was plotted to illustrate the connections among the trials involved. Comparison results in the network were exhibited in a forest plot. Furthermore, the surface under the cumulative ranking curve (SUCRA) was introduced to rank the treatments for each endpoint.. A total of 11 trials were selected from 1,625 identifications. No significant difference in the common treatment was observed for the endpoints CR and ORR. In terms of OS, CPX-351 (HR: 0.77, 95% CrI: 0.63, 0.94) and HiDAC plus MK-8776 (HR: 0.80, 95% CrI: 0.68, 0.93) showed a superiority over the common salvage regimen in the short term, while HiDAC plus MK-8776 (HR: 0.80, 95% CrI: 0.70, 0.93) and Ara-C plus vosaroxin (HR: 0.86, 95% CrI: 0.74, 0.99) outperformed the common salvage regimen for the 3-year OS. In addition, clofarabine plus Ara-C (HR: 0.61, 95% CrI: 0.53, 0.69) and CPX-351 (HR: 0.71, 95% CrI: 0.60, 0.83) were confirmed to be efficacious in enhancing the rate of EFS.. Referring to the network outcome and SUCRA value, clofarabine plus Ara-C (CR: 79.05%, ORR: 80.02%) and Ara-C plus vosaroxin (CR: 75.42%, ORR: 73.43%) were potentially the top two choices for both CR and ORR. CPX-351 (1-year OS: 91.36%), HiDAC plus MK-8776 (3-year OS: 94.23%) and clofarabine plus Ara-C (1-year EFS: 97.34%) yielded the highest probabilities to be the optimal choices for 1-year OS, 3-year OS and 1-year EFS, respectively.

Topics: Bayes Theorem; Cytarabine; Disease-Free Survival; Histone Deacetylase Inhibitors; Humans; Leukemia, Myeloid, Acute; Naphthyridines; Neoplasm Recurrence, Local; Odds Ratio; Pyrazoles; Pyrimidines; Remission Induction; Salvage Therapy; Survival Rate; Thiazoles

Acute myeloid leukemia (AML) represents a disease with a very poor outcome and remains an area of significant unmet need necessitating novel therapeutic strategies. Among novel therapeutic agents, vosaroxin is a first-in-class anticancer quinolone derivative that targets topoisomerase II and induces site-selective double-strand breaks in DNA, leading to tumor cell apoptosis. Areas covered: Herein, the authors provide a comprehensive review of the preclinical development of vosaroxin. This includes coverage of vosaroxin's mechanism of action in addition to its pharmacology and of the main studies reported over the past few years with vosaroxin when used to treat adult AML. Expert opinion: Given that vosaroxin is associated with fewer potential side effects, it may be of benefit to elderly patients with relapsed/refractory AML and to those with additional comorbidities who have previously received an anthracycline and cytarabine combination. Furthermore, vosaroxin also was seen to be active in multidrug-resistant preclinical models. However, further studies have to be performed to better evaluate its place in the armamentarium against AML.

Topics: Adult; Aged; Animals; Antineoplastic Agents; Apoptosis; DNA Breaks, Double-Stranded; Drug Evaluation, Preclinical; Drug Resistance, Multiple; Drug Resistance, Neoplasm; Humans; Leukemia, Myeloid, Acute; Naphthyridines; Thiazoles; Topoisomerase Inhibitors

Vosaroxin is a quinolone compound that intercalates DNA and induces TP53-independent apoptosis, demonstrating activity against acute myeloid leukemia (AML) in Phase I-III trials. Here, we examine vosaroxin's mechanism of action and pharmacology, and we review its use in AML to date, focusing on details of individual clinical trials. Most recently, when combined with cytarabine in a randomized Phase III trial (VALOR), vosaroxin improved outcomes versus cytarabine alone for relapsed/refractory AML in patients older than 60 years and for patients in early relapse. We consider its continued role in the context of a multifaceted strategy against AML, including its current use in clinical trials. Prospective use will define its role in the evolving landscape of AML therapy.

Topics: Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Apoptosis; Clinical Trials, Phase I as Topic; Clinical Trials, Phase II as Topic; Clinical Trials, Phase III as Topic; Humans; Leukemia, Myeloid, Acute; Naphthyridines; Thiazoles; Treatment Outcome; Tumor Suppressor Protein p53

The outcomes of patients with relapsed or refractory acute myeloid leukemia (AML) are dismal, and effective treatment options in this patient population are therefore desperately needed. Vosaroxin is a first-in-class anticancer quinolone derivative that has shown promising activity in patients with relapsed or refractory AML.. Studies in relapsed/refractory AML, including a large randomized phase III trial, have shown improved response rates when vosaroxin was combined with cytarabine, which translated to prolonged survival in certain subsets of patients, including older patients. Given the encouraging results of vosaroxin in the relapsed/refractory setting, several studies are also evaluating vosaroxin in older patients with untreated AML who are not candidates for intensive chemotherapy. The results from clinical trials evaluating vosaroxin in both treatment naïve and relapsed/refractory AML will be reviewed. Expert Commentary: Vosaroxin has shown significant promise in the management of AML, especially in older patients with relapsed/refractory disease. As vosaroxin has been associated with increased toxicity in some studies, appropriate dosing and patient selection will be crucial to determine the future role of vosaroxin in AML.

Topics: Age Factors; Animals; Antineoplastic Agents; Clinical Trials as Topic; Drug Evaluation, Preclinical; Drug Resistance, Neoplasm; Humans; Leukemia, Myeloid, Acute; Naphthyridines; Recurrence; Retreatment; Thiazoles; Treatment Outcome

Vosaroxin is a first-in-class anticancer quinolone derivative that targets topoisomerase II and induces site-selective double-strand breaks in DNA, leading to tumor cell apoptosis. Vosaroxin has chemical and pharmacologic characteristics distinct from other topoisomerase II inhibitors due to its quinolone scaffold. The efficacy and safety of vosaroxin in combination with cytarabine were evaluated in patients with relapsed/refractory acute myeloid leukemia (AML) in a phase III, randomized, multicenter, double-blind, placebo-controlled study (VALOR). In this study, the addition of vosaroxin produced a 1.4-month improvement in median overall survival (OS; 7.5 months with vosaroxin/cytarabine vs. 6.1 months with placebo/cytarabine; hazard ratio [HR] 0.87, 95 % confidence interval [CI] 0.73-1.02; unstratified log-rank p [Formula: see text] 0.061; stratified log-rank p [Formula: see text]0.024), with the greatest OS benefit observed in patients ≥60 years of age (7.1 vs. 5.0 months; HR 0.75, 95 % CI 0.62-0.92; p [Formula: see text]0.003) and patients with early relapse (6.7 vs. 5.2 months; HR 0.77, 95 % CI 0.59-1.00; p [Formula: see text] 0.039), two AML patient groups that typically have poor prognosis. Here we review the chemical and pharmacologic properties of vosaroxin, how these properties are distinct from those of currently available topoisomerase II inhibitors, how they may contribute to the efficacy and safety profile observed in the VALOR trial, and the status of clinical development of vosaroxin for treatment of AML.

Topics: Aged; Aged, 80 and over; Animals; Antineoplastic Combined Chemotherapy Protocols; Cytarabine; Double-Blind Method; Haplorhini; Humans; Leukemia, Myeloid, Acute; Mice; Middle Aged; Naphthyridines; Quinolones; Rats; Thiazoles

Vosaroxin is a first-in-class anti-cancer quinolone that inhibits topoisomerase-II leading to cell cycle arrest and apoptosis. It has shown efficacy in a range of solid organ and haematopoietic tumours in vitro, and several clinical trials are underway or completed in the field of Acute Myeloid Leukaemia (AML). The treatment of relapsed and refractory AML is a clinical challenge, where long-term survival is rare without allogeneic haematopoietic stem cell transplantation.. We review the data from the published clinical trials of vosaroxin, including the recently presented Phase III VALOR study. In combination with intermediate dose cytarabine, vosaroxin almost doubled complete response (CR) rates in relapsed and refractory AML compared with cytarabine alone, and prolonged median survival by 1.4 months.. Vosaroxin is a promising new agent in the treatment of AML, with the potential to improve CR rates in a high-risk group of patients with relapsed and refractory AML. However, higher CR rates have been associated with higher rates of treatment-related morbidity and mortality, especially in elderly/unfit patients. Maximising the potential of vosaroxin will therefore require the identification of patients most likely to benefit from vosaroxin-containing combination regimens.

Topics: Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Clinical Trials as Topic; Cytarabine; Humans; Leukemia, Myeloid, Acute; Naphthyridines; Recurrence; Thiazoles; Topoisomerase Inhibitors; Treatment Failure

A number of new agents in acute myeloid leukemia (AML) have held much promise in recent years, but most have failed to change the therapeutic landscape. Indeed, with the exception of gemtuzumab ozogamicin (which was subsequently voluntarily withdrawn from the commercial market), no new agent has been approved for acute myeloid leukemia (AML) beyond the 7 + 3 regimen, which was has been in use for over 40 years. This review touches upon the potential reasons for these failures and explores the newer therapeutic approaches being pursued in AML.

Topics: Aminoglycosides; Antibodies, Monoclonal, Humanized; Antineoplastic Agents; Arabinonucleosides; Benzothiazoles; Cytosine; Gemtuzumab; Humans; Hydroxamic Acids; Leukemia, Myeloid, Acute; Naphthyridines; Phenylurea Compounds; Prognosis; Randomized Controlled Trials as Topic; Recurrence; Remission Induction; Staurosporine; Survival Analysis; Thiazoles; Treatment Failure; Vorinostat

The antineoplastic quinolone derivative vosaroxin (SNS-595, Sunesis, South San Francisco, CA, USA) was first described in 2002. It represents a novel class of anticancer drugs and is currently in a Phase III clinical trial for relapsed and refractory acute myeloid leukemia (AML). AML is the most common form of acute leukemia in adults and is increasing in incidence due to the aging of the American population. Despite advances in diagnosis, prognostic prediction, and treatment in younger age groups, there has been little improvement in survival among patients over 60 years of age, who make up the majority of those affected.. The development of vosaroxin, its mechanism of action, pharmacology, and metabolism, and the preclinical and clinical data to date will be covered.. Despite its structural dissimilarity, vosaroxin has mechanisms of action similar to the anthracyclines and anthracenediones already in use for the treatment of AML. However, unlike these agents, vosaroxin is not a P-gp substrate, appears to be unaffected by overexpression of P-gp or TP53 mutations, and may be useful in the treatment of AML, especially in the elderly.

Topics: Animals; Antineoplastic Agents; Clinical Trials as Topic; Drug Evaluation, Preclinical; Humans; Leukemia, Myeloid, Acute; Naphthyridines; Randomized Controlled Trials as Topic; Thiazoles

Topics: Aged; Aged, 80 and over; Antineoplastic Combined Chemotherapy Protocols; Cytarabine; Female; Humans; Leukemia, Myeloid, Acute; Male; Middle Aged; Naphthyridines; Recurrence; Thiazoles

Vosaroxin is a first-in-class anticancer quinolone derivative that intercalates DNA and inhibits topoisomerase II. This study assessed the safety and tolerability of vosaroxin plus cytarabine in patients with relapsed/refractory acute myeloid leukemia. Escalating vosaroxin doses (10-minute infusion; 10-90 mg/m(2); days 1, 4) were given in combination with cytarabine on one of two schedules: schedule A (24-hour continuous intravenous infusion, 400 mg/m(2)/day, days 1-5) or schedule B (2-hour intravenous infusion, 1 g/m(2)/day, days 1-5). Following dose escalation, enrollment was expanded at the maximum tolerated dose. Of 110 patients enrolled, 108 received treatment. The maximum tolerated dose of vosaroxin was 80 mg/m(2) for schedule A (dose-limiting toxicities: grade 3 bowel obstruction and stomatitis) and was not reached for schedule B (recommended phase 2 dose: 90 mg/m(2)). In the efficacy population (all patients in first relapse or with primary refractory disease treated with vosaroxin 80-90 mg/m(2); n=69), the complete remission rate was 25% and the complete remission/complete remission with incomplete blood count recovery rate was 28%. The 30-day all-cause mortality rate was 2.5% among all patients treated at a dose of 80-90 mg/m(2). Based upon these results, a phase 3 trial of vosaroxin plus cytarabine was initiated in patients with relapsed/refractory acute myeloid leukemia. (Clinicaltrials.gov identifier: NCT00541866).

Topics: Adolescent; Adult; Aged; Antineoplastic Combined Chemotherapy Protocols; Cohort Studies; Cytarabine; Drug Resistance, Neoplasm; Female; Follow-Up Studies; Humans; Leukemia, Myeloid, Acute; Male; Maximum Tolerated Dose; Middle Aged; Naphthyridines; Neoplasm Recurrence, Local; Neoplasm Staging; Prognosis; Remission Induction; Salvage Therapy; Survival Rate; Thiazoles; Young Adult

This phase 2 study (N = 116) evaluated single-agent vosaroxin, a first-in-class anticancer quinolone derivative, in patients ≥60 years of age with previously untreated unfavourable prognosis acute myeloid leukaemia. Dose regimen optimization was explored in sequential cohorts (A: 72 mg/m(2)  d 1, 8, 15; B: 72 mg/m(2)  d 1, 8; C: 72 mg/m(2) or 90 mg/m(2)  d 1, 4). The primary endpoint was combined complete remission rate (complete remission [CR] plus CR with incomplete platelet recovery [CRp]). Common (>20%) grade ≥3 adverse events were thrombocytopenia, febrile neutropenia, anaemia, neutropenia, sepsis, pneumonia, stomatitis and hypokalaemia. Overall CR and CR/CRp rates were 29% and 32%; median overall survival (OS) was 7·0 months; 1-year OS was 34%. Schedule C (72 mg/m(2) ) had the most favourable safety and efficacy profile, with faster haematological recovery (median 27 d) and lowest incidence of aggregate sepsis (24%) and 30-d (7%) and 60-d (17%) all-cause mortality; at this dose and schedule, CR and CR/CRp rates were 31% and 35%, median OS was 7·7 months and 1-year OS was 38%. Overall, vosaroxin resulted in low early mortality and an encouraging response rate; vosaroxin 72 mg/m(2)  d 1, 4 is recommended for further study in this population. Registered at www.clinicaltrials.gov: #NCT00607997.

Topics: Aged; Aged, 80 and over; Antineoplastic Agents; Dose-Response Relationship, Drug; Drug Administration Schedule; Female; Humans; Infusions, Intravenous; Leukemia, Myeloid, Acute; Male; Middle Aged; Naphthyridines; Prognosis; Survival Analysis; Thiazoles; Treatment Outcome

The development of new treatments for older patients with acute myeloid leukemia is an active area, but has met with limited success. Vosaroxin, a quinolone-derived intercalating agent has several properties that could prove beneficial. Initial clinical studies showed it to be well-tolerated in older patients with relapsed/refractory disease. In vitro data suggested synergy with cytarabine (Ara-C). To evaluate vosaroxin, we performed 2 randomized comparisons within the "Pick a Winner" program. A total of 104 patients were randomized to vosaroxin vs low-dose Ara-C (LDAC) and 104 to vosaroxin + LDAC vs LDAC. When comparing vosaroxin with LDAC, neither response rate (complete recovery [CR]/complete recovery with incomplete count recovery [CRi], 26% vs 30%; odds ratio [OR], 1.16 (0.49-2.72); P = .7) nor 12-month survival (12% vs 31%; hazard ratio [HR], 1.94 [1.26-3.00]; P = .003) showed benefit for vosaroxin. Likewise, in the vosaroxin + LDAC vs LDAC comparison, neither response rate (CR/CRi, 38% vs 34%; OR, 0.83 [0.37-1.84]; P = .6) nor survival (33% vs 37%; HR, 1.30 [0.81-2.07]; P = .3) was improved. A major reason for this lack of benefit was excess early mortality in the vosaroxin + LDAC arm, most obviously in the second month following randomization. At its first interim analysis, the Data Monitoring and Ethics Committee recommended closure of the vosaroxin-containing trial arms because a clinically relevant benefit was unlikely.

Topics: Aged; Aged, 80 and over; Antineoplastic Combined Chemotherapy Protocols; Cytarabine; Dose-Response Relationship, Drug; Female; Follow-Up Studies; Humans; Leukemia, Myeloid, Acute; Male; Middle Aged; Naphthyridines; Neoplasm Recurrence, Local; Neoplasm Staging; Prognosis; Prospective Studies; Remission Induction; Survival Rate; Thiazoles

Safe and effective treatments are urgently needed for patients with relapsed or refractory acute myeloid leukaemia. We investigated the efficacy and safety of vosaroxin, a first-in-class anticancer quinolone derivative, plus cytarabine in patients with relapsed or refractory acute myeloid leukaemia.. This phase 3, double-blind, placebo-controlled trial was undertaken at 101 international sites. Eligible patients with acute myeloid leukaemia were aged 18 years of age or older and had refractory disease or were in first relapse after one or two cycles of previous induction chemotherapy, including at least one cycle of anthracycline (or anthracenedione) plus cytarabine. Patients were randomly assigned 1:1 to vosaroxin (90 mg/m(2) intravenously on days 1 and 4 in a first cycle; 70 mg/m(2) in subsequent cycles) plus cytarabine (1 g/m(2) intravenously on days 1-5) or placebo plus cytarabine through a central interactive voice system with a permuted block procedure stratified by disease status, age, and geographical location. All participants were masked to treatment assignment. The primary efficacy endpoint was overall survival and the primary safety endpoint was 30-day and 60-day all-cause mortality. Efficacy analyses were done by intention to treat; safety analyses included all treated patients. This study is registered with ClinicalTrials.gov, number NCT01191801.. Between Dec 17, 2010, and Sept 25, 2013, 711 patients were randomly assigned to vosaroxin plus cytarabine (n=356) or placebo plus cytarabine (n=355). At the final analysis, median overall survival was 7·5 months (95% CI 6·4-8·5) in the vosaroxin plus cytarabine group and 6·1 months (5·2-7·1) in the placebo plus cytarabine group (hazard ratio 0·87, 95% CI 0·73-1·02; unstratified log-rank p=0·061; stratified p=0·024). A higher proportion of patients achieved complete remission in the vosaroxin plus cytarabine group than in the placebo plus cytarabine group (107 [30%] of 356 patients vs 58 [16%] of 355 patients, p<0·0001). Early mortality was similar between treatment groups (30-day: 28 [8%] of 355 patients in the vosaroxin plus cytarabine group vs 23 [7%] of 350 in the placebo plus cytarabine group; 60-day: 70 [20%] vs 68 [19%]). Treatment-related deaths occurred at any time in 20 (6%) of 355 patients given vosaroxin plus cytarabine and in eight (2%) of 350 patients given placebo plus cytarabine. Treatment-related serious adverse events occurred in 116 (33%) and 58 (17%) patients in each group, respectively. Grade 3 or worse adverse events that were more frequent in the vosaroxin plus cytarabine group than in the placebo plus cytarabine group included febrile neutropenia (167 [47%] vs 117 [33%]), neutropenia (66 [19%] vs 49 [14%]), stomatitis (54 [15%] vs 10 [3%]), hypokalaemia (52 [15%] vs 21 [6%]), bacteraemia (43 [12%] vs 16 [5%]), sepsis (42 [12%] vs 18 [5%]), and pneumonia (39 [11%] vs 26 [7%]).. Although there was no significant difference in the primary endpoint between groups, the prespecified secondary analysis stratified by randomisation factors suggests that the addition of vosaroxin to cytarabine might be of clinical benefit to some patients with relapsed or refractory acute myeloid leukaemia.. Sunesis Pharmaceuticals.

Topics: Adult; Aged; Aged, 80 and over; Antineoplastic Combined Chemotherapy Protocols; Cytarabine; Disease-Free Survival; Double-Blind Method; Female; Humans; Kaplan-Meier Estimate; Leukemia, Myeloid, Acute; Male; Middle Aged; Naphthyridines; Neoplasm Recurrence, Local; Remission Induction; Thiazoles; Treatment Outcome

This study of vosaroxin evaluated dose-limiting toxicity (DLT), maximum-tolerated dose (MTD), pharmacokinetics (PK), clinical activity and pharmacodynamics in relapsed/refractory leukemia. Dosing was weekly (days 1, 8 and 15) or twice weekly (days 1, 4, 8 and 11). Seventy-three treated patients had a median age of 65 years, 85% had acute myeloid leukemia and 78% had refractory disease. Weekly schedule: 42 patients received 18-90 mg/m(2); MTD was 72 mg/m(2). Twice-weekly schedule: 31 patients received 9-50 mg/m(2); MTD was 40 mg/m(2). DLT was stomatitis; primary non-hematologic toxicity was reversible gastrointestinal symptoms and febrile neutropenia. Thirty-day all-cause mortality was 11%. Five patients had complete or incomplete remissions; median duration was 3.1 months. A morphologic leukemia-free state (bone marrow blast reduction to <5%) occurred in 11 additional patients. Antileukemic activity was associated with total dose or weekly time above 1 μmol/l plasma vosaroxin concentration (P<0.05). Vosaroxin exposure was dose proportional over 9-90 mg/m(2). The average terminal half-life was ~25 h and clearance was non-renal. No induction or inhibition of vosaroxin metabolism was evident. Vosaroxin-induced DNA damage was detected as increased intracellular γH2AX. Vosaroxin had an acceptable safety profile, linear PK and encouraging clinical activity in relapsed/refractory leukemia.

Topics: Adult; Aged; Aged, 80 and over; Drug Resistance, Neoplasm; Female; Follow-Up Studies; Humans; Leukemia, Myeloid, Acute; Male; Middle Aged; Naphthyridines; Neoplasm Recurrence, Local; Neoplasm Staging; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Salvage Therapy; Thiazoles; Treatment Outcome; Young Adult

The survival rate for acute myeloid leukemia remains unacceptably low, in large part owing to resistance to chemotherapy and high rates of relapse. There is an urgent need to develop new therapeutic modalities, in particular such that are tolerated by patients over the age of 60 years, who form the bulk of new acute myeloid leukemia diagnoses. Vosaroxin (SNS-595), a second-generation topoisomerase II inhibitor and DNA intercalating agent, shows promising preclinical and clinical activity against acute myeloid leukemia. Venetoclax (ABT-199), a selective Bcl-2 inhibitor, was recently approved for the treatment of acute myeloid leukemia.. The objective of this study was to determine the anti-leukemic activity and the underlying molecular mechanisms for the combination of venetoclax and vosaroxin in acute myeloid leukemia cell lines and primary patient samples ex vivo.. Using both acute myeloid leukemia cell lines and primary patient samples, annexin V/propidium iodide staining and flow cytometry analyses were used to quantify apoptosis induced by venetoclax or vosaroxin, alone or in combination, with subsequent western blotting analyses to assess levels of Bcl-2 family proteins. Alkaline comet assays were performed to quantify DNA damage induced by the two agents and to determine the effect of venetoclax on DNA repair. Finally, colony-forming assays were conducted on normal human CD34+ cord blood cells and primary acute myeloid leukemia patient samples to determine the effect of venetoclax and vosaroxin on normal hematopoietic and leukemic progenitor cells.. We found that venetoclax and vosaroxin synergistically induced apoptosis in multiple acute myeloid leukemia cell lines. Although vosaroxin could partially abrogate the increase of Mcl-1 protein induced by venetoclax, it could not abrogate the increased binding of Bim to Mcl-1 induced by venetoclax. Cooperative induction of DNA damage occurred within 8 h of treatment with venetoclax plus vosaroxin. Moreover, repair of DNA damage induced by vosaroxin was significantly attenuated by venetoclax. The combination also synergistically induced apoptosis in primary acute myeloid leukemia patient samples and significantly reduced the colony formation capacity of acute myeloid leukemia progenitor cells, while sparing normal hematopoietic progenitor cells.. Vosaroxin and venetoclax synergistically induce apoptosis in acute myeloid leukemia cells and cooperatively target acute myeloid leukemia progenitor cells while sparing normal hematopoietic progenitor cells. Our results support the clinical testing of vosaroxin in combination with venetoclax for treating patients with acute myeloid leukemia, especially in the elderly population.

Topics: Adult; Aged; Antineoplastic Agents; Apoptosis; Bridged Bicyclo Compounds, Heterocyclic; Drug Synergism; Female; Humans; Leukemia, Myeloid, Acute; Male; Middle Aged; Myeloid Cell Leukemia Sequence 1 Protein; Naphthyridines; Neoplasm Recurrence, Local; Proto-Oncogene Proteins c-bcl-2; Sulfonamides; Thiazoles; Tumor Cells, Cultured; Young Adult

MEK inhibitors are new promising anticancer drugs. The aim of this study was to investigate the effect of the combination treatment of voreloxin with the MEK inhibitor TAK-733 on HL60 myeloid leukemia cells.. MAPK activity, cell viability, apoptosis, oxidative stress induction and AIF (apoptosis-inducing factor) distribution were assessed in HL60 cells cultured with each drug alone or with both drugs.. TAK-733 alone at 5 μM significantly reduced MAPK activity and did not influence viability and apoptosis in HL60 cells. Voreloxin at concentration of 0.03-0.48 μM reduced cell viability and increased apoptosis rate. Incubation with both drugs caused further inhibition of cell viability and increased apoptosis associated with generation of reactive oxygen species (ROS) and nuclear translocation of AIF.. Combination of TAK-733 and voreloxin can exert a synergistic anticancer effect in myeloid leukemia cells.

Topics: Antineoplastic Combined Chemotherapy Protocols; Apoptosis; Apoptosis Inducing Factor; Cell Nucleus; Cell Survival; Drug Synergism; HL-60 Cells; Humans; Leukemia, Myeloid, Acute; MAP Kinase Kinase Kinases; Microscopy, Confocal; Naphthyridines; Protein Kinase Inhibitors; Pyridones; Pyrimidinones; Reactive Oxygen Species; Thiazoles

Despite significant advances in diagnosis and supportive care, the majority of patients diagnosed with acute myeloid leukemia (AML) ultimately die of their disease. Standard intensive induction treatment continues to comprise cytarabine and a topoisomerase II (topo II) poison, usually an anthracycline. Vosaroxin , a novel first-in-class quinolone derivative has been developed for use in the treatment of AML as a new-generation topo II inhibitor. It has shown promising activity as a monotherapy and also in combination with intermediate dose cytarabine (IDAC) in relapsed and refractory patient cohorts with minimal toxicity and good tolerability.. The authors discuss the mechanism of action of vosaroxin, the pharmacokinetics, safety and tolerability, preclinical and clinical trial results available as well as areas of ongoing research.. Vosaroxin has shown efficacy as a novel cytotoxic agent, and despite a similar mechanism of action has significant advantages over anthracyclines. It evades common resistance pathways of p53 and P-glycoprotein (P- gp) and does not appear to generate significant reactive oxygen species (ROS) associated with these agents. Should future investigation confirm its efficacy and advantageous safety profile, vosaroxin could potentially replace older generation topoisomerase poisons in the treatment of AML and other malignant conditions.

Topics: Anthracyclines; Antineoplastic Agents; Humans; Leukemia, Myeloid, Acute; Naphthyridines; Thiazoles; Topoisomerase II Inhibitors

Topoisomerase II is essential for the maintenance of DNA integrity and the survival of proliferating cells. Topoisomerase II poisons, including etoposide and doxorubicin, inhibit enzyme-mediated DNA ligation causing the accumulation of double-stranded breaks and have been front-line drugs for the treatment of leukemia for many years. Voreloxin is a first-in-class anti-cancer quinolone derivative that intercalates DNA and inhibits topoisomerase II. The efficacy and mechanisms of action of voreloxin in acute myeloid leukaemia were addressed in this study.. Primary acute myeloid leukemia blasts (n = 88) and myeloid cell lines were used in vitro to study voreloxin through viability assays to assess cell killing and synergy with other drugs. Apoptosis and cell cycling were assessed by flow cytometry. DNA relaxation assays were utilized to determine that voreloxin was active on topoisomerase II.. The mean lethal dose 50% (LD(50)) (± standard deviation) of voreloxin for primary acute myeloid leukemia blasts was 2.30 μM (± 1.87). Synergy experiments between voreloxin and cytarabine identified synergism in 22 of 25 primary acute myeloid leukemia samples tested, with a mean combination index of 0.79. Apoptosis was shown to increase in a dose-dependent manner. Furthermore, voreloxin was active in the p53-null K562 cell line suggesting that the action of voreloxin is not affected by p53 status. The action of voreloxin on topoisomerase II was confirmed using a DNA relaxation assay.. Voreloxin may provide an interesting addition to the cache of drugs available for the treatment of acute myeloid leukemia, a disease with a poor long-term survival. In addition to its potent action as a single agent in dividing cells, the synergy we demonstrated between voreloxin and cytarabine recommends further investigation of this topoisomerase II inhibitor.

Topics: Apoptosis; Cell Culture Techniques; Cell Cycle; Cell Line, Tumor; Cell Proliferation; Cytarabine; DNA Topoisomerases, Type II; Dose-Response Relationship, Drug; Drug Synergism; Female; Gene Deletion; Genes, p53; Humans; Lethal Dose 50; Leukemia, Myeloid, Acute; Male; Middle Aged; Myeloid Cells; Naphthyridines; Thiazoles; Topoisomerase II Inhibitors

Do patients with therapy-related acute myeloid leukemia (t-AML) have a poor prognosis independent of other predictive variables such as cytogenetics or molecular determinants? Limited data exist to answer this question in part because t-AML is often considered together with AML following myelodysplastic syndromes (MDS) in the category of secondary AML. This discussion provides some insight, based primarily on two published retrospective reviews of the German cooperative groups, into the question of whether t-AML is an independent adverse variable.

Topics: Adenine; Anthracyclines; Antineoplastic Agents; Biomarkers, Tumor; Cytarabine; Cytogenetics; Female; Germany; Humans; Leukemia, Myeloid, Acute; Middle Aged; Myelodysplastic Syndromes; Naphthalimides; Naphthyridines; Organophosphonates; Prognosis; Remission Induction; Retrospective Studies; Survival Rate; Thiazoles