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UK Health Security Agency is required to investigate the pathogenesis of emerging or re-emerging infections and to test novel interventions, such as vaccines and therapeutics against these and other diseases, such as tuberculosis and Ebola, that have a significant impact on human health world-wide. Research into the causative agents (mainly BSL 3 and 4) using a wide range of animal species as pre-clinical models brings a number of challenges in terms of effective biocontainment to address human safety whilst optimising delivery of scientific objectives and the welfare of the animals. Here we describe the strategies used for high containment of species that include mice, ferrets, hamsters, rabbits and macaques that have been infected with high consequence pathogens. To ensure relevance of these models we frequently challenge by the aerosol route and monitor the development of disease and protective or therapeutic efficacy by methodologies similar to those used in the clinic. We have devised methods of sampling that can inform on pathogenesis and immune function that include lung lavage and medical imaging such as computed tomography and positron emission tomography-computed tomography. Imaging assists our assessment of progression to disease whilst providing refinement in application of early humane endpoints. We have developed directional flow containment systems that provide quantifiable operator protection whilst allowing group housing and a wide range of enrichment strategies appropriate for each species. Furthermore, we have demonstrated our improvements in animal welfare through use of a software-based Animal Welfare Assessment Grid that was developed with help of NC3Rs funding and enables us to quantify the lifetime experience of animals.
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The BCG vaccine is given to millions of children globally but efficacy wanes over time and differences in the immune systems between infants and adults can influence vaccine efficacy. To this end, 34 rhesus macaques were vaccinated with BCG within seven days of birth and blood samples were collected over 88 weeks for quantification of blood cell populations. Overall, the composition of cell populations did not change significantly between BCG vaccinated and unvaccinated groups, and that BCG vaccination did not perturb normal development. In comparison to adult macaques, higher numbers of CD4+ T-cells, Tregs and NK cells were measured in the infant age group, suggesting a potential bias towards immunosuppressive and innate immune populations. Antigen-specific IFNγ secreting cell frequencies in infant BCG vaccinated animals were detectable in peripheral blood samples for 36 weeks after vaccination but declined following this. To evaluate the long-term impact of infant BCG vaccination on subsequent revaccination with BCG, a pilot study of three adult macaques received an aerosol BCG revaccination approximately 3 years after their initial BCG vaccination as infants. This induced an increase in PPD-specific IFNγ secreting cells, and increased secretion of the cytokines IFNγ and IL-1ß, following stimulation with other microorganisms, which are signals associated with trained innate immunity.
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Animais Recém-Nascidos , Vacina BCG , Imunização Secundária , Macaca mulatta , Macaca mulatta/imunologia , Vacina BCG/imunologia , Animais Recém-Nascidos/imunologia , Linfócitos/imunologia , Citocinas/sangue , Citocinas/imunologia , Animais , Masculino , FemininoRESUMO
Introduction: Mycobacteria are known to exert a range of heterologous effects on the immune system. The mycobacteria-based Freund's Complete Adjuvant is a potent non-specific stimulator of the immune response used in immunization protocols promoting antibody production, and Mycobacterium bovis Bacille Calmette Guérin (BCG) vaccination has been linked with decreased morbidity and mortality beyond the specific protection it provides against tuberculosis (TB) in some populations and age groups. The role of heterologous antibodies in this phenomenon, if any, remains unclear and under-studied. Methods: We set out to evaluate antibody responses to a range of unrelated pathogens following infection with Mycobacterium tuberculosis (M.tb) and vaccination with BCG or a candidate TB vaccine, MTBVAC, in non-human primates. Results: We demonstrate a significant increase in the titer of antibodies against SARS-CoV-2, cytomegalovirus, Epstein-Barr virus, tetanus toxoid, and respiratory syncytial virus antigens following low-dose aerosol infection with M.tb. The magnitude of some of these responses correlated with TB disease severity. However, vaccination with BCG administered by the intradermal, intravenous or aerosol routes, or intradermal delivery of MTBVAC, did not increase antibody responses against unrelated pathogens. Discussion: Our findings suggest that it is unlikely that heterologous antibodies contribute to the non-specific effects of these vaccines. The apparent dysregulation of B cell responses associated with TB disease warrants further investigation, with potential implications for risk of B cell cancers and novel therapeutic strategies.
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Vacina BCG , Mycobacterium tuberculosis , Tuberculose , Vacinação , Animais , Vacina BCG/imunologia , Vacina BCG/administração & dosagem , Tuberculose/imunologia , Tuberculose/prevenção & controle , Mycobacterium tuberculosis/imunologia , Anticorpos Antibacterianos/imunologia , Anticorpos Antibacterianos/sangue , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/sangue , Vacinas contra a Tuberculose/imunologia , Vacinas contra a Tuberculose/administração & dosagem , Feminino , Macaca mulatta , SARS-CoV-2/imunologia , COVID-19/imunologia , COVID-19/prevenção & controle , Imunidade Heteróloga , MasculinoRESUMO
ABSTRACT: Although NPM1-mutated acute myeloid leukemia (AML) carries a generally favorable prognosis, many patients still relapse and die. Previous studies identified several molecular and clinical features associated with poor outcomes; however, only FLT3-internal tandem duplication (ITD) mutation and adverse karyotype are currently used for risk stratification because of inconsistent results and uncertainty about how other factors should influence treatment, particularly given the strong prognostic effect of postinduction measurable residual disease (MRD). Here, we analyzed a large group of patients with NPM1 mutations (NPM1mut) AML enrolled in prospective trials (National Cancer Research Institute [NCRI] AML17 and AML19, n = 1357) to delineate the impact of baseline molecular and clinical features, postinduction MRD status, and treatment intensity on the outcome. FLT3-ITD (hazard ratio [HR], 1.28; 95% confidence interval [CI], 1.01-1.63), DNMT3A (HR, 1.65; 95% CI, 1.32-2.05), WT1 (HR, 1.74; 95% CI, 1.27-2.38), and non-ABD NPM1mut (HR, 1.64; 95% CI, 1.22-2.21) were independently associated with poorer overall survival (OS). These factors were also strongly associated with MRD positivity. For patients who achieved MRD negativity, these mutations (except FLT3-ITD) were associated with an increased cumulative incidence of relapse (CIR) and poorer OS. However, apart from the few patients with adverse cytogenetics, we could not identify any group of MRD-negative patients with a CIR >40% or with benefit from allograft in first remission. Intensified chemotherapy with the FLAG-Ida (fludarabine, cytarabine, granulocyte colony-stimulating factor, and idarubicin) regimen was associated with improved outcomes in all subgroups, with greater benefits observed in the high-risk molecular subgroups.
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Leucemia Mieloide Aguda , Mutação , Proteínas Nucleares , Nucleofosmina , Tirosina Quinase 3 Semelhante a fms , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/terapia , Leucemia Mieloide Aguda/mortalidade , Leucemia Mieloide Aguda/tratamento farmacológico , Proteínas Nucleares/genética , Pessoa de Meia-Idade , Feminino , Masculino , Adulto , Idoso , Tirosina Quinase 3 Semelhante a fms/genética , Prognóstico , Adulto Jovem , Neoplasia Residual/genética , DNA Metiltransferase 3A , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Proteínas WT1/genética , DNA (Citosina-5-)-Metiltransferases/genética , Adolescente , Resultado do Tratamento , Idoso de 80 Anos ou maisRESUMO
ABSTRACT: Selection of patients with NPM1-mutated acute myeloid leukemia (AML) for allogeneic transplant in first complete remission (CR1-allo) remains controversial because of a lack of robust data. Consequently, some centers consider baseline FLT3-internal tandem duplication (ITD) an indication for transplant, and others rely on measurable residual disease (MRD) status. Using prospective data from the United Kingdom National Cancer Research Institute AML17 and AML19 studies, we examined the impact of CR1-allo according to peripheral blood NPM1 MRD status measured by quantitative reverse transcription polymerase chain reaction after 2 courses of induction chemotherapy. Of 737 patients achieving remission, MRD was positive in 19%. CR1-allo was performed in 46% of MRD+ and 17% of MRD- patients. We observed significant heterogeneity of overall survival (OS) benefit from CR1-allo according to MRD status, with substantial OS advantage for MRD+ patients (3-year OS with CR1-allo vs without: 61% vs 24%; hazard ratio [HR], 0.39; 95% confidence interval [CI], 0.24-0.64; P < .001) but no benefit for MRD- patients (3-year OS with CR1-allo vs without: 79% vs 82%; HR, 0.82; 95% CI, 0.50-1.33; P = .4). Restricting analysis to patients with coexisting FLT3-ITD, again CR1-allo only improved OS for MRD+ patients (3-year OS, 45% vs 18%; compared with 83% vs 76% if MRD-); no interaction with FLT3 allelic ratio was observed. Postinduction molecular MRD reliably identifies those patients who benefit from allogeneic transplant in first remission. The AML17 and AML19 trials were registered at www.isrctn.com as #ISRCTN55675535 and #ISRCTN78449203, respectively.
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Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda , Neoplasia Residual , Nucleofosmina , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Tirosina Quinase 3 Semelhante a fms/genética , Quimioterapia de Indução , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/terapia , Mutação , Estudos Prospectivos , Indução de Remissão , Transplante HomólogoRESUMO
PURPOSE: To determine the optimal induction chemotherapy regimen for younger adults with newly diagnosed AML without known adverse risk cytogenetics. PATIENTS AND METHODS: One thousand thirty-three patients were randomly assigned to intensified (fludarabine, cytarabine, granulocyte colony-stimulating factor, and idarubicin [FLAG-Ida]) or standard (daunorubicin and Ara-C [DA]) induction chemotherapy, with one or two doses of gemtuzumab ozogamicin (GO). The primary end point was overall survival (OS). RESULTS: There was no difference in remission rate after two courses between FLAG-Ida + GO and DA + GO (complete remission [CR] + CR with incomplete hematologic recovery 93% v 91%) or in day 60 mortality (4.3% v 4.6%). There was no difference in OS (66% v 63%; P = .41); however, the risk of relapse was lower with FLAG-Ida + GO (24% v 41%; P < .001) and 3-year event-free survival was higher (57% v 45%; P < .001). In patients with an NPM1 mutation (30%), 3-year OS was significantly higher with FLAG-Ida + GO (82% v 64%; P = .005). NPM1 measurable residual disease (MRD) clearance was also greater, with 88% versus 77% becoming MRD-negative in peripheral blood after cycle 2 (P = .02). Three-year OS was also higher in patients with a FLT3 mutation (64% v 54%; P = .047). Fewer transplants were performed in patients receiving FLAG-Ida + GO (238 v 278; P = .02). There was no difference in outcome according to the number of GO doses, although NPM1 MRD clearance was higher with two doses in the DA arm. Patients with core binding factor AML treated with DA and one dose of GO had a 3-year OS of 96% with no survival benefit from FLAG-Ida + GO. CONCLUSION: Overall, FLAG-Ida + GO significantly reduced relapse without improving OS. However, exploratory analyses show that patients with NPM1 and FLT3 mutations had substantial improvements in OS. By contrast, in patients with core binding factor AML, outcomes were excellent with DA + GO with no FLAG-Ida benefit.
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Idarubicina , Leucemia Mieloide Aguda , Vidarabina/análogos & derivados , Tirosina Quinase 3 Semelhante a fms , Adulto , Humanos , Gemtuzumab/uso terapêutico , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/diagnóstico , Intervalo Livre de Progressão , Citarabina/uso terapêutico , Recidiva Local de Neoplasia/tratamento farmacológico , Vidarabina/uso terapêutico , Proteínas Nucleares/genética , Mutação , Fatores de Ligação ao Core , Recidiva , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversosRESUMO
Improving outcomes for older patients with acute myeloid leukaemia remains an unmet need. As part of the LI-1 trial, we evaluated lenalidomide (LEN) in combination with low-dose cytosine arabinoside (LDAC) in patients aged >60 years unfit for intensive therapy and compared this to LDAC alone. Two hundred and two patients, randomised 1:1, were evaluable. Overall response rate (CR + CRi) was higher for LDAC + LEN versus LDAC (26% and 13.7% respectively p = 0.031). However, there was no difference in overall survival between the arms (14% and 11.5% at 2 years for LDAC + LEN and LDAC respectively). The addition of LEN was associated with increased toxicity and supportive care requirements.
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Citarabina , Leucemia Mieloide Aguda , Humanos , Idoso , Lenalidomida/uso terapêutico , Indução de Remissão , Leucemia Mieloide Aguda/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêuticoRESUMO
ABSTRACT: Assessment of measurable residual disease (MRD) by quantitative reverse transcription polymerase chain reaction is strongly prognostic in patients with NPM1-mutated acute myeloid leukemia (AML) treated with intensive chemotherapy; however, there are no data regarding its utility in venetoclax-based nonintensive therapy, despite high efficacy in this genotype. We analyzed the prognostic impact of NPM1 MRD in an international real-world cohort of 76 previously untreated patients with NPM1-mutated AML who achieved complete remission (CR)/CR with incomplete hematological recovery following treatment with venetoclax and hypomethylating agents (HMAs) or low-dose cytarabine (LDAC). A total of 44 patients (58%) achieved bone marrow (BM) MRD negativity, and a further 14 (18%) achieved a reduction of ≥4 log10 from baseline as their best response, with no difference between HMAs and LDAC. The cumulative rates of BM MRD negativity by the end of cycles 2, 4, and 6 were 25%, 47%, and 50%, respectively. Patients achieving BM MRD negativity by the end of cycle 4 had 2-year overall of 84% compared with 46% if MRD was positive. On multivariable analyses, MRD negativity was the strongest prognostic factor. A total of 22 patients electively stopped therapy in BM MRD-negative remission after a median of 8 cycles, with 2-year treatment-free remission of 88%. In patients with NPM1-mutated AML attaining remission with venetoclax combination therapies, NPM1 MRD provides valuable prognostic information.
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Compostos Bicíclicos Heterocíclicos com Pontes , Leucemia Mieloide Aguda , Nucleofosmina , Sulfonamidas , Humanos , Prognóstico , Mutação , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Citarabina , Neoplasia Residual/genéticaRESUMO
Intravenously (IV) delivered BCG provides superior tuberculosis (TB) protection compared with the intradermal (ID) route in non-human primates (NHPs). We examined how γδ T cell responses changed in vivo after IV BCG vaccination of NHPs, and whether these correlated with protection against aerosol M. tuberculosis challenge. In the circulation, Vδ2 T cell populations expanded after IV BCG vaccination, from a median of 1.5% (range: 0.8-2.3) of the CD3+ population at baseline, to 5.3% (range: 1.4-29.5) 4 weeks after M. tb, and were associated with TB protection. This protection was related to effector and central memory profiles; homing markers; and production of IFN-γ, TNF-α and granulysin. In comparison, Vδ2 cells did not expand after ID BCG, but underwent phenotypic and functional changes. When Vδ2 responses in bronchoalveolar lavage (BAL) samples were compared between routes, IV BCG vaccination resulted in highly functional mucosal Vδ2 cells, whereas ID BCG did not. We sought to explore whether an aerosol BCG boost following ID BCG vaccination could induce a γδ profile comparable to that induced with IV BCG. We found evidence that the aerosol BCG boost induced significant changes in the Vδ2 phenotype and function in cells isolated from the BAL. These results indicate that Vδ2 population frequency, activation and function are characteristic features of responses induced with IV BCG, and the translation of responses from the circulation to the site of infection could be a limiting factor in the response induced following ID BCG. An aerosol boost was able to localise activated Vδ2 populations at the mucosal surfaces of the lung. This vaccine strategy warrants further investigation to boost the waning human ID BCG response.
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Tuberculosis remains a major health threat globally and a more effective vaccine than the current Bacillus Calmette Guerin (BCG) is required, either to replace or boost it. The Spore-FP1 mucosal vaccine candidate is based on the fusion protein of Ag85B-Acr-HBHA/heparin-binding domain, adsorbed on the surface of inactivated Bacillus subtilis spores. The candidate conferred significant protection against Mycobacterium. tuberculosis challenge in naïve guinea pigs and markedly improved protection in the lungs and spleens of animals primed with BCG. We then immunized rhesus macaques with BCG intradermally, and subsequently boosted with one intradermal and one aerosol dose of Spore-FP1, prior to challenge with low dose aerosolized M. tuberculosis Erdman strain. Following vaccination, animals did not show any adverse reactions and displayed higher antigen specific cellular and antibody immune responses compared to BCG alone but this did not translate into significant improvement in disease pathology or bacterial burden in the organs.
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Mycobacterium bovis , Mycobacterium tuberculosis , Vacinas contra a Tuberculose , Tuberculose , Cobaias , Animais , Vacina BCG , Macaca mulatta , Antígenos de Bactérias , Tuberculose/prevenção & controle , EsporosRESUMO
Addition of gemtuzumab ozogamicin (GO) to induction chemotherapy improves outcomes in older patients with acute myeloid leukemia (AML), but it is uncertain whether a fractionated schedule provides additional benefit to a single dose. We randomized 852 older adults (median age, 68-years) with AML/high-risk myelodysplasia to GO on day 1 (GO1) or on days 1 and 4 (GO2) of course 1 induction. The median follow-up period was 50.2 months. Although complete remission (CR) rates after course 1 did not significantly differ between arms (GO2, 63%; GO1, 57%; odds ratio [OR], 0.78; P = .08), there were significantly more patients who achieved CR with a measurable residual disease (MRD)<0.1% (50% vs 41%; OR, 0.72; P = .027). This differential MRD reduction with GO2 varied across molecular subtypes, being greatest for IDH mutations. The 5-year overall survival (OS) was 29% for patients in the GO2 arm and 24% for those in the GO1 arm (hazard ratio [HR], 0.89; P = .14). In a sensitivity analysis excluding patients found to have adverse cytogenetics or TP53 mutations, the 5-year OS was 33% for GO2 and 26% for GO1 (HR, 0.83; P = .045). In total, 228 (27%) patients received an allogeneic transplantation in first remission. Posttransplant OS was superior in the GO2 arm (HR, 0.67; P = .033); furthermore, the survival advantage from GO2 in the sensitivity analysis was lost when data of patients were censored at transplantation. In conclusion, GO2 was associated with a greater reduction in MRD and improved survival in older adults with nonadverse risk genetics. This benefit from GO2 was dependent on allogeneic transplantation to translate the better leukemia clearance into improved survival. This trial was registered at www.isrctn.com as #ISRCTN 31682779.
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Daunorrubicina , Leucemia Mieloide Aguda , Humanos , Idoso , Gemtuzumab/uso terapêutico , Anticorpos Monoclonais Humanizados , Citarabina , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Reino Unido , Aminoglicosídeos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversosRESUMO
Patients with FLT3-mutated AML have a high relapse rate and suboptimal outcomes. Many have co-mutations suitable for measurable residual disease (MRD) monitoring by RT-qPCR and those destined to relapse can be identified by high or rising levels of MRD, called molecular failure. This provides a window for pre-emptive intervention, but there is little evidence to guide treatment. The use of FLT3 inhibitors (FLT3i) appears attractive but their use has not yet been evaluated. We identified 56 patients treated with FLT3i at molecular failure. The FLT3 mutation was an ITD in 52, TKD in 7 and both in 3. Over half of patients had previously received midostaurin. Molecular failure occurred at a median 9.2 months from diagnosis and was treated with gilteritinib (n = 38), quizartinib (n = 7) or sorafenib (n = 11). 60% achieved a molecular response, with 45% reaching MRD negativity. Haematological toxicity was low, and 22 patients were bridged directly to allogeneic transplant with another 6 to donor lymphocyte infusion. 2-year overall survival was 80% (95%CI 69-93) and molecular event-free survival 56% (95%CI 44-72). High-sensitivity next-generation sequencing for FLT3-ITD at molecular failure identified patients more likely to benefit. FLT3i monotherapy for molecular failure is a promising strategy which merits evaluation in prospective studies.
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Leucemia Mieloide Aguda , Terapia de Salvação , Humanos , Tirosina Quinase 3 Semelhante a fms/antagonistas & inibidores , Tirosina Quinase 3 Semelhante a fms/genética , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Mutação , Recidiva Local de Neoplasia , Estudos Prospectivos , Inibidores de Proteínas Quinases/uso terapêuticoRESUMO
Liposomal daunorubicin and cytarabine (CPX-351) improved overall survival (OS) compared with 7+3 chemotherapy in older patients with secondary acute myeloid leukemia (AML); to date, there have been no randomized studies in younger patients. The high-risk cohort of the UK NCRI AML19 trial (ISRCTN78449203) compared CPX-351 with FLAG-Ida in younger adults with newly diagnosed adverse cytogenetic AML or high-risk myelodysplastic syndromes (MDS). A total of 189 patients were randomized (median age, 56 years). Per clinical criteria, 49% of patients had de novo AML, 20% had secondary AML, and 30% had high-risk MDS. MDS-related cytogenetics were present in 73% of the patients, with a complex karyotype in 49%. TP53 was the most common mutated gene, in 43%. Myelodysplasia-related gene mutations were present in 75 (44%) patients. The overall response rate (CR + CRi) after course 2 was 64% and 76% for CPX-351 and FLAG-Ida, respectively. There was no difference in OS (13.3 months vs 11.4 months) or event-free survival in multivariable analysis. However, relapse-free survival was significantly longer with CPX-351 (median 22.1 vs 8.35 months). There was no difference between the treatment arms in patients with clinically defined secondary AML or those with MDS-related cytogenetic abnormalities; however, an exploratory subgroup of patients with MDS-related gene mutations had significantly longer OS with CPX-351 (median 38.4 vs 16.3 months). In conclusion, the OS of younger patients with adverse risk AML/MDS was not significantly different between CPX-351 and FLAG-Ida.
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Leucemia Mieloide Aguda , Síndromes Mielodisplásicas , Adulto , Humanos , Idoso , Pessoa de Meia-Idade , Daunorrubicina/uso terapêutico , Citarabina/uso terapêutico , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Síndromes Mielodisplásicas/tratamento farmacológico , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/complicações , Cariótipo , Reino UnidoRESUMO
The survival of acute myeloid leukaemia (AML) patients aged over 60 has been suboptimal historically, whether they are treated using hypomethylating agents, low-dose cytarabine (LDAC) or venetoclax-based regimens. Progress is being made, however, for subgroups with favourable molecular or cytogenetic findings. Arginine metabolism plays a key role in AML pathophysiology. We report the only randomised study of LDAC with recombinant arginase BCT-100 versus LDAC alone in older AML patients unsuitable for intensive therapy. Eighty-three patients were randomised to the study. An overall response rate was seen in 19.5% (all complete remission [CR]) and 15% (7.5% each in CR and CR without evidence of adequate count recovery [CRi]) of patients in the LDAC+BCT-100 and LDAC arms respectively (odds ratio 0.73, confidence interval 0.23-2.33; p = 0.592). No significant difference in overall or median survival between treatment arms was seen. The addition of BCT-100 to LDAC was well tolerated.
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Citarabina , Leucemia Mieloide Aguda , Humanos , Pessoa de Meia-Idade , Idoso , Arginase , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Polietilenoglicóis/uso terapêuticoRESUMO
Innovative cross-over study designs were explored in non-human primate (NHP) studies to determine the value of this approach for the evaluation of drug efficacy against tuberculosis (TB). Firstly, the pharmacokinetics (PK) of each of the drugs Isoniazid (H), Rifampicin (R), Pyrazinamide (Z) and Ethambutol (E), that are standardly used for the treatment of tuberculosis, was established in the blood of macaques after oral dosing as a monotherapy or in combination. Two studies were conducted to evaluate the pharmacokinetics and pharmacodynamics of different drug combinations using cross-over designs. The first employed a balanced, three-period Pigeon design with an extra period; this ensured that treatment by period interactions and carry-over could be detected comparing the treatments HR, HZ and HRZ using H37Rv as the challenge strain of Mycobacterium tuberculosis (M. tb). Although the design accounted for considerable variability between animals, the three regimens evaluated could not be distinguished using any of the alternative endpoints assessed. However, the degree of pathology achieved using H37Rv in the model during this study was less than expected. Based on these findings, a second experiment using a classical AB/BA design comparing HE with HRZ was conducted using the M. tb Erdman strain. More extensive pathology was observed, and differences in computerized tomography (CT) scores and bacteriology counts in the lungs were detected, although due to the small group sizes, clearer differences were not distinguished. Type 1 T helper (Th1) cell response profiles were characterized using the IFN-γ ELISPOT assay and revealed differences between drug treatments that corresponded to decreases in disease burden. Therefore, the studies performed support the utility of the NHP model for the determination of PK/PD of TB drugs, although further work is required to optimize the use of cross-over study designs.
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Treating adverse risk myelodysplastic syndromes with azacitidine exacerbates thrombocytopenia. We report a study of eltrombopag in combination with azacitidine using a 3 + 3 cohort design. Patients with baseline platelets of <150 × 109 /l received eltrombopag ranging from 25 to 300 mg. An 8-day pre-phase of eltrombopag was followed by two cycles of combined therapy. Amongst 31 patients, there were no dose-limiting toxicities. The maximum tolerated dose (MTD) was 300 mg. Transient increases in bone marrow blasts at day 8 were common but no patient had protocol-defined progression following eltrombopag monotherapy. Marrow response rates after three and six treatment cycles were 32% and 29% respectively. In all, 70% of patients treated below and 36% treated at the MTD achieved a modified International Working Group 2006 platelet response at the end of cycle two. Of the platelet transfusion independent patients at baseline, 67% treated at the MTD became transfusion dependent during the first two cycles of treatment. Apart from lack of disease progression, our findings concur with a previously reported Phase III study (A StUdy of eltromboPag in myelodysPlastic SyndrOmes Receiving azaciTidine [SUPPORT]). We conclude that eltrombopag/azacitidine is safe in terms of conventional measures defined by adverse-event reporting. However, in light of SUPPORT and our own descriptive findings regarding efficacy, further combination studies in high-risk disease should be considered with caution.
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Azacitidina , Benzoatos , Hidrazinas , Síndromes Mielodisplásicas , Pirazóis , Azacitidina/uso terapêutico , Benzoatos/uso terapêutico , Combinação de Medicamentos , Humanos , Hidrazinas/uso terapêutico , Síndromes Mielodisplásicas/tratamento farmacológico , Pirazóis/uso terapêutico , Resultado do TratamentoRESUMO
Secondary acute myeloid leukaemia (AML) has a poor outcome following "3 + 7-like" chemotherapy. While CPX-351 has been approved for patients aged 60-75, the optimal treatment, or comparator, in younger patients is less clear. The MRC AML15 trial randomised younger patients between daunorubicin and ara-C (DA) and DA plus etoposide (ADE) and ADE and fludarabine, cytarabine, idarubicin, and granulocyte colony-stimulating factor (FLAG-Ida) induction. Overall results failed to show an overall survival benefit for FLAG-Ida despite a reduction in relapse, the outcome of patients <60 years with secondary AML compared to DA/ADE was not reported. In this group (n = 115) response to induction was not different [complete remission/complete remission with incomplete haematological response 81% vs. 79%), however, 5-year overall survival and relapse free survival was superior for FLAG-Ida [37% vs. 27%, stratified hazard ratio (HR) 0·45 (0·33-0·90) P = 0·02 and 41% vs. 22%; stratified HR 0·54 (0·31-0·96) P = 0·04] respectively, suggesting that younger patients with secondary AML may benefit from treatment intensification and that "3 + 7" may not be the optimal comparator in trials for this group of patients.
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Idarubicina , Leucemia Mieloide Aguda , Segunda Neoplasia Primária , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica , Citarabina , Seguimentos , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Humanos , Idarubicina/uso terapêutico , Leucemia Mieloide Aguda/tratamento farmacológico , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Segunda Neoplasia Primária/tratamento farmacológico , Indução de Remissão , VidarabinaRESUMO
Induction therapy for acute myeloid leukaemia (AML) has changed with the approval of a number of new agents. Clinical guidelines can struggle to keep pace with an evolving treatment and evidence landscape and therefore identifying the most appropriate front-line treatment is challenging for clinicians. Here, we combined drug eligibility criteria and genetic risk stratification into a digital format, allowing the full range of possible treatment eligibility scenarios to be defined. Using exemplar cases representing each of the 22 identified scenarios, we sought to generate consensus on treatment choice from a panel of nine aUK AML experts. We then analysed >2500 real-world cases using the same algorithm, confirming the existence of 21/22 of these scenarios and demonstrating that our novel approach could generate a consensus AML induction treatment in 98% of cases. Our approach, driven by the use of decision trees, is an efficient way to develop consensus guidance rapidly and could be applied to other disease areas. It has the potential to be updated frequently to capture changes in eligibility criteria, novel therapies and emerging trial data. An interactive digital version of the consensus guideline is available.