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1.
Adv Ther ; 39(6): 2831-2849, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35430670

RESUMO

INTRODUCTION: We previously demonstrated that real-world progression (rwP) can be ascertained from unstructured electronic health record (EHR)-derived documents using a novel abstraction approach for patients with advanced non-small cell lung cancer (base case). The objective of this methodological study was to assess the reliability, clinical relevance, and the need for disease-specific adjustments of this abstraction approach in five additional solid tumor types. METHODS: Patients with metastatic breast cancer (mBC), advanced melanoma (aMel), small cell lung cancer (SCLC), metastatic renal cell carcinoma (mRCC), and advanced gastric/esophageal cancer (aGEC) were selected from a real-world database. Disease-specific additions to the base case were implemented as needed. The resulting abstraction approach was applied to each disease cohort to capture rwP events and dates. To provide comprehensive clinical context, real-world progression-free survival (rwPFS) and time to progression (rwTTP) were compared to real-world overall survival (rwOS), time to next treatment (rwTTNT), and time to treatment discontinuation (rwTTD). Endpoint estimates were assessed using the Kaplan-Meier method. Correlations between real-world endpoints and rwOS were calculated using Spearman's ρ. RESULTS: Additions to the base-case rwP abstraction approach were required for mBC, aMel, and SCLC. Inter-abstractor agreement for rwP occurrence, irrespective of date, ranged from 88% to 97%. Occurrence of clinically relevant downstream events (new antineoplastic systemic therapy start, antineoplastic systemic therapy end, or death relative to the rwP event) ranged from 59% (aMel) to 72% (mBC). Median rwPFS ranged from 3.7 (aMel) to 7.7 (mBC) months, and median rwTTP ranged from 4.6 (aMel) to 8.3 (mRCC) months. Correlations between rwOS and rwPFS ranged from 0.52 (aMel) to 0.82 (SCLC). The correlation between rwOS and rwTTD was often lower relative to other comparisons (range 0.40-0.62). CONCLUSION: Derivation of a rwP variable from EHR documentation is feasible and reliable across the five solid tumors. Endpoint analyses show that rwP produces clinically meaningful information.


Assuntos
Neoplasias da Mama , Carcinoma Pulmonar de Células não Pequenas , Carcinoma de Células Renais , Neoplasias Renais , Neoplasias Pulmonares , Carcinoma de Pequenas Células do Pulmão , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Feminino , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Reprodutibilidade dos Testes , Estudos Retrospectivos
2.
JCO Clin Cancer Inform ; 5: 326-337, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33764818

RESUMO

PURPOSE: To address the need for more accurate risk stratification models for cancer immuno-oncology, this study aimed to develop a machine-learned Bayesian network model (BNM) for predicting outcomes in patients with metastatic renal cell carcinoma (mRCC) being treated with immunotherapy. METHODS: Patient-level data from the randomized, phase III CheckMate 025 clinical trial comparing nivolumab with everolimus for second-line treatment in patients with mRCC were used to develop the BNM. Outcomes of interest were overall survival (OS), all-cause adverse events, and treatment-related adverse events (TRAE) over 36 months after treatment initiation. External validation of the model's predictions for OS was conducted using data from select centers from the International Metastatic Renal Cell Carcinoma Database Consortium (IMDC). RESULTS: Areas under the receiver operating characteristic curve (AUCs) for BNM-based classification of OS using baseline data were 0.74, 0.71, and 0.68 over months 12, 24, and 36, respectively. AUC for OS at 12 months increased to 0.86 when treatment response and progression status in year 1 were included as predictors; progression and response at 12 months were highly prognostic of all outcomes over the 36-month period. AUCs for adverse events and treatment-related adverse events were approximately 0.6 at 12 months but increased to approximately 0.7 by 36 months. Sensitivity analysis comparing the BNM with machine learning classifiers showed comparable performance. Test AUC on IMDC data for 12-month OS was 0.71 despite several variable imbalances. Notably, the BNM outperformed the IMDC risk score alone. CONCLUSION: The validated BNM performed well at prediction using baseline data, particularly with the inclusion of response and progression at 12 months. Additionally, the results suggest that 12 months of follow-up data alone may be sufficient to inform long-term survival projections in patients with mRCC.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Teorema de Bayes , Carcinoma de Células Renais/tratamento farmacológico , Intervalo Livre de Doença , Humanos , Imunoterapia , Neoplasias Renais/terapia
3.
Future Oncol ; 17(3): 333-347, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33074018

RESUMO

In recent years, regulatory bodies have increasingly recognized the utility of real-world evidence (RWE) for supplementing and supporting clinical trial data in new drug applications. Nevertheless, the integration of RWE into established regulatory processes is complex and the generation of 'regulatory-grade' real-world data faces operational, methodological, data-related and policy-related challenges. In parallel with this evolving role for RWE, immuno-oncology therapies have emerged as leading cancer treatments and are expected to continue to play a central role in the future. In this article, we review the current literature on the use of RWE for regulatory submissions, with a focus on novel anticancer immunotherapies, and discuss the utility and current limitations of RWE in the context of drug development and regulatory approvals.


Assuntos
Medicina Baseada em Evidências , Imunoterapia/legislação & jurisprudência , Neoplasias/tratamento farmacológico , Ensaios Clínicos como Assunto/legislação & jurisprudência , Desenvolvimento de Medicamentos/legislação & jurisprudência , Humanos , Neoplasias/imunologia , Vigilância de Produtos Comercializados , Resultado do Tratamento
4.
J Med Econ ; 24(1): 79-86, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33334176

RESUMO

BACKGROUND: In August 2018, the US FDA granted accelerated approval for nivolumab in small cell lung cancer (SCLC) that has progressed after platinum-based chemotherapy and at least one other line of therapy. The objective of this study was to evaluate the cost-effectiveness of nivolumab vs. usual care as third-line (3 L) therapy for patients with recurrent SCLC (rSCLC) from the health payer perspective. Given the potential for a meaningful fraction of treated patients to achieve long-term response to nivolumab, we also assessed the impact of using mixture cure modeling (MCM) vs. parametric survival modeling on survival estimates and cost-effectiveness from the US Medicare payer perspective. METHODS: We created a partitioned survival decision model to assess the cost-effectiveness of 3 L nivolumab vs. usual care in rSCLC, based on observed US treatment patterns. Using this approach, we assessed the impact of extrapolating long-term survival from the CheckMate 032 trial, using both MCM and standard parametric curve fits. Nivolumab survival, resource use, and Grade 3/4 adverse event rates were derived from CheckMate 032. Usual care survival, resource use, and costs were derived from an analysis of patients receiving 3 L treatment for rSCLC in the SEER-Medicare registry. We applied 2020 Wholesale Acquisition Cost for drugs and 2020 CMS reimbursement for procedures. Utilities were derived from the literature. We estimated life years (LY), quality-adjusted life years (QALYs), and costs over a lifetime horizon. RESULTS: MCM and parametric survival model extrapolations resulted in 0.43 versus 0.38 more LYs, 0.34 versus 0.30 more QALYs, and $69,308 versus $61,336 more expenditure for nivolumab vs. usual care, respectively. The costs per QALY gained using mixture cure versus parametric survival modeling were $204,386 and $207,431, respectively. CONCLUSIONS: Mixture cure modeling was equivalent compared to parametric modeling in estimating the cost-effectiveness of nivolumab-based therapy due to the small fraction of patients achieving a long-term response with nivolumab (12.9%).


Assuntos
Neoplasias Pulmonares , Carcinoma de Pequenas Células do Pulmão , Idoso , Análise Custo-Benefício , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Medicare , Recidiva Local de Neoplasia/tratamento farmacológico , Nivolumabe/uso terapêutico , Anos de Vida Ajustados por Qualidade de Vida , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológico , Estados Unidos
5.
J Immunother Cancer ; 8(2)2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32661115

RESUMO

Immuno-oncologics (IOs) differ from chemotherapies as they prime the patient's immune system to attack the tumor, rather than directly destroying cancer cells. The IO mechanism of action leads to durable responses and prolonged survival in some patients. However, providing robust evidence of the long-term benefits of IOs at health technology assessment (HTA) submission presents several challenges for manufacturers. The aim of this article was to identify, analyze, categorize, and further explore the key challenges that regulators, HTA agencies, and payers commonly encounter when assessing the long-term benefits of IO therapies. Insights were obtained from an international, multi-stakeholder steering committee (SC) and expert panels comprising of payers, economists, and clinicians. The selected individuals were tasked with developing a summary of challenges specific to IOs in demonstrating their long-term benefits at HTA submission. The SC and expert panels agreed that standard methods used to assess the long-term benefit of anticancer drugs may have limitations for IO therapies. Three key areas of challenges were identified: (1) lack of a disease model that fully captures the mechanism of action and subsequent patient responses; (2) estimation of longer-term outcomes, including a lack of agreement on ideal methods of survival analyses and extrapolation of survival curves; and (3) data limitations at the time of HTA submission, for which surrogate survival end points and real-world evidence could prove useful. A summary of the key challenges facing manufacturers when submitting evidence at HTA submission was developed, along with further recommendations for manufacturers in what evidence to produce. Despite almost a decade of use, there remain significant challenges around how best to demonstrate the long-term benefit of checkpoint inhibitor-based IOs to HTA agencies, clinicians, and payers. Manufacturers can potentially meet or mitigate these challenges with a focus on strengthening survival analysis methodology. Approaches to doing this include identifying reliable biomarkers, intermediate and surrogate end points, and the use of real-world data to inform and validate long-term survival projections. Wider education across all stakeholders-manufacturers, payers, and clinicians-in considering the long-term survival benefit with IOs is also important.


Assuntos
Imunoterapia/métodos , Neoplasias/tratamento farmacológico , Avaliação da Tecnologia Biomédica/métodos , Humanos , Neoplasias/patologia
6.
Cancer Treat Rev ; 70: 75-87, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30125799

RESUMO

Patients with recurrent or metastatic cancer commonly suffer from debilitating toxicity associated with conventional treatment modalities, as well as disease-related symptoms, often with a concomitant negative impact on health-related quality of life (HRQoL). Patient-reported outcomes (PROs) provide important insights into the patient experience in clinical trials. Nivolumab is a programmed death-1 receptor inhibitor that extends survival in patients with recurrent or metastatic disease in multiple tumor types. In this review, we summarize published PRO analyses from eight phase II-IV clinical trials with nivolumab for the treatment of melanoma, non-small cell lung cancer, renal cell carcinoma (RCC), and squamous cell carcinoma of the head and neck (SCCHN). Symptom burden, physical functioning, and HRQoL were measured using generic, cancer-specific, and tumor type-specific validated PRO instruments. Nivolumab showed sustained stabilization across all tumor types and, in some cases, clinically meaningful improvement in HRQoL, whereas standard of care therapies often led to deteriorations. Exploratory analyses found a positive correlation between baseline HRQoL scores and overall survival in RCC, and between baseline HRQoL scores and healthcare resource utilization in SCCHN, suggesting that patient-reported symptoms at treatment initiation may have clinical value. In the era of value-based oncology care, stakeholders are increasingly interested in PRO findings to guide clinical, regulatory, and reimbursement decisions. However, missing data remain a significant challenge in PRO analyses, including in nivolumab trials. Future clinical trials in immuno-oncology should incorporate PRO data collection, including beyond treatment discontinuation or trial completion to assess the long-term effects of treatment on HRQoL.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Antineoplásicos/uso terapêutico , Neoplasias/tratamento farmacológico , Medidas de Resultados Relatados pelo Paciente , Qualidade de Vida , Humanos , Nivolumabe
7.
PLoS Genet ; 14(7): e1007514, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29985927

RESUMO

The stringent response is characterized by (p)ppGpp synthesis resulting in repression of translation and reprogramming of the transcriptome. In Staphylococcus aureus, (p)ppGpp is synthesized by the long RSH (RelA/SpoT homolog) enzyme, RelSau or by one of the two short synthetases (RelP, RelQ). RSH enzymes are characterized by an N-terminal enzymatic domain bearing distinct motifs for (p)ppGpp synthetase or hydrolase activity and a C-terminal regulatory domain (CTD) containing conserved motifs (TGS, DC and ACT). The intramolecular switch between synthetase and hydrolase activity of RelSau is crucial for the adaption of S. aureus to stress (stringent) or non-stress (relaxed) conditions. We elucidated the role of the CTD in the enzymatic activities of RelSau. Growth pattern, transcriptional analyses and in vitro assays yielded the following results: i) in vivo, under relaxed conditions, as well as in vitro, the CTD inhibits synthetase activity but is not required for hydrolase activity; ii) under stringent conditions, the CTD is essential for (p)ppGpp synthesis; iii) RelSau lacking the CTD exhibits net hydrolase activity when expressed in S. aureus but net (p)ppGpp synthetase activity when expressed in E. coli; iv) the TGS and DC motifs within the CTD are required for correct stringent response, whereas the ACT motif is dispensable, v) Co-immunoprecipitation indicated that the CTD interacts with the ribosome, which is largely dependent on the TGS motif. In conclusion, RelSau primarily exists in a synthetase-OFF/hydrolase-ON state, the TGS motif within the CTD is required to activate (p)ppGpp synthesis under stringent conditions.


Assuntos
Proteínas de Bactérias/genética , Regulação Bacteriana da Expressão Gênica , Hidrolases/genética , Ligases/genética , Staphylococcus aureus/fisiologia , Adaptação Fisiológica/genética , Motivos de Aminoácidos/fisiologia , Proteínas de Bactérias/metabolismo , Hidrolases/metabolismo , Ligases/metabolismo , Ribossomos/metabolismo , Estresse Fisiológico/fisiologia
8.
Value Health ; 20(4): 705-709, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28408015

RESUMO

BACKGROUND: Economic evaluations often measure an intervention effect with mean overall survival (OS). Emerging types of cancer treatments offer the possibility of being "cured" in that patients can become long-term survivors whose risk of death is the same as that of a disease-free person. Describing cured and noncured patients with one shared mean value may provide a biased assessment of a therapy with a cured proportion. OBJECTIVE: The purpose of this article is to explain how to incorporate the heterogeneity from cured patients into health economic evaluation. METHODS: We analyzed clinical trial data from patients with advanced melanoma treated with ipilimumab (Ipi; n = 137) versus glycoprotein 100 (gp100; n = 136) with statistical methodology for mixture cure models. Both cured and noncured patients were subject to background mortality not related to cancer. RESULTS: When ignoring cured proportions, we found that patients treated with Ipi had an estimated mean OS that was 8 months longer than that of patients treated with gp100. Cure model analysis showed that the cured proportion drove this difference, with 21% cured on Ipi versus 6% cured on gp100. The mean OS among the noncured cohort patients was 10 and 9 months with Ipi and gp100, respectively. The mean OS among cured patients was 26 years on both arms. When ignoring cured proportions, we found that the incremental cost-effectiveness ratio (ICER) when comparing Ipi with gp100 was $324,000/quality-adjusted life-year (QALY) (95% confidence interval $254,000-$600,000). With a mixture cure model, the ICER when comparing Ipi with gp100 was $113,000/QALY (95% confidence interval $101,000-$154,000). CONCLUSIONS: This analysis supports using cure modeling in health economic evaluation in advanced melanoma. When a proportion of patients may be long-term survivors, using cure models may reduce bias in OS estimates and provide more accurate estimates of health economic measures, including QALYs and ICERs.


Assuntos
Anticorpos Monoclonais/economia , Anticorpos Monoclonais/uso terapêutico , Antineoplásicos/economia , Antineoplásicos/uso terapêutico , Custos de Medicamentos , Glicoproteínas/economia , Glicoproteínas/uso terapêutico , Melanoma/tratamento farmacológico , Melanoma/economia , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/economia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais/efeitos adversos , Antineoplásicos/efeitos adversos , Viés , Análise Custo-Benefício , Feminino , Glicoproteínas/efeitos adversos , Humanos , Ipilimumab , Estimativa de Kaplan-Meier , Masculino , Melanoma/mortalidade , Pessoa de Meia-Idade , Modelos Econômicos , Anos de Vida Ajustados por Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Indução de Remissão , Neoplasias Cutâneas/mortalidade , Sobreviventes , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
9.
Oncotarget ; 8(17): 28595-28613, 2017 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-28404894

RESUMO

ValloVax is a placental endothelium derived vaccine which induces tissue-nonspecific antitumor immunity by blocking tumor angiogesis. To elucidate mechanisms of action, we showed that production of ValloVax, which involves treating placental endothelial cells with IFN-gamma, results in upregulation of HLA and costimulatory molecules. It was shown that in mixed lymphocyte reaction, ValloVax induces Type I cytokines and allo-proliferative responses. Plasma from ValloVax immunized mice was capable of killing in vitro tumor-like endothelium but not control endothelium. Using defined antigens associated with tumor endothelial cells, specific molecular entities were identified as being targeted by ValloVax induced antibodies. Binding of predominantly IgG antibodies to ValloVax cells was confirmed by flow cytometry. Further suggesting direct killing of tumor endothelial cells was expression of TUNEL positive cells, as well as, reduction in tumor oxygenation. Supporting a role for antibody mediated responses, cell depletion experiments suggested a predominant role of B cells in maintaining an intact anti-tumor endothelial response. Adoptive transfer experiments suggested that infusion of CD3+ T cells from immunized mice was sufficient to transfer tumor protection. Generation of memory T cells selective to tumor endothelial specific markers was observed. Functional confirmation of memory responses was observed in tumor rechallenge experiments. Furthermore, we observed that both PD-1 or CTLA-4 blockade augmented antitumor effects of ValloVax. These data suggest a T cell induced B cell mediated anti-tumor endothelial response and set the framework clinical trials through elucidation of mechanism of action.


Assuntos
Vacinas Anticâncer/imunologia , Endotélio/imunologia , Imunidade , Neoplasias/imunologia , Neoplasias/patologia , Transferência Adotiva , Animais , Reações Cruzadas/imunologia , Citocinas/biossíntese , Citotoxicidade Imunológica , Modelos Animais de Doenças , Células Endoteliais/imunologia , Feminino , Antígenos de Histocompatibilidade/imunologia , Imunização , Memória Imunológica , Imunoterapia , Interferon gama/farmacologia , Ativação Linfocitária/imunologia , Linfócitos/imunologia , Linfócitos/metabolismo , Camundongos , Neoplasias/terapia , Especificidade de Órgãos/imunologia
10.
Am J Manag Care ; 23(1): 54-61, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28141932

RESUMO

OBJECTIVES: With the introduction of more effective anticancer agents that prolong survival, there is a need for new methods to define the clinical value of treatments. The objective of this preliminary qualitative and quantitative analysis was to assess the utility of an expanded portfolio of survival metrics to differentiate the value of anticancer agents. STUDY DESIGN: A literature review was conducted of phase 3 trial data, reported in regulatory submissions within the last 10 years of agents for 6 metastatic cancers (breast cancer, colorectal cancer [CRC], melanoma, non-small cell lung cancer [NSCLC], prostate cancer [PC], and renal cell cancer [RCC]). METHODS: A new, simplified cost-value analysis tool was applied using survival outcomes and total drug costs. Metrics included median overall survival (OS), mean OS, 1-year survival rate, and number needed to treat (NNT) to avoid 1 death at 1 year. Survival results were compiled and compared both within and across trials by tumor type. Total drug costs were calculated by multiplying each agent's cost per month (from October/November 2013, based on the database Price Rx/Medi-Span) by duration of therapy. RESULTS: Relative clinical value for each agent was not consistent across survival outcomes. In 3 tumor types, both the highest improvement in median OS and the highest improvement in mean OS occurred with the same anticancer agent (ipilimumab with melanoma, pemetrexed with NSCLC, and sunitinib with RCC); the highest improvement in the 1-year survival rate and the lowest NNT occurred together with the same anticancer agent in 5 tumor types (bevacizumab with CRC, ipilimumab with melanoma, erlotinib with NSCLC, abiraterone with PC, and temsirolimus with RCC). In the cost-value analysis, agents were inconsistent and achieved a high relative value with some survival outcomes, but not others. CONCLUSIONS: This analysis suggests that any 1 metric may not completely characterize the expected survival benefit of all patients. The cost-value analysis tool may be applied to trial data and may be useful in helping to make treatment decisions, regardless of the agent's effectiveness. A combined metric will be needed, as well as further research that includes more mature data, other tumor types, and emerging treatments.


Assuntos
Antineoplásicos/economia , Análise Custo-Benefício/economia , Custos de Medicamentos , Neoplasias/tratamento farmacológico , Neoplasias/mortalidade , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Ensaios Clínicos Fase III como Assunto , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Neoplasias/patologia , Medição de Risco , Análise de Sobrevida , Estados Unidos
11.
J Transl Med ; 14: 90, 2016 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-27071457

RESUMO

The mechanisms underlying discrimination between "self" and "non-self", a central immunological principle, require careful consideration in immune oncology therapeutics where eliciting anti-cancer immunity must be weighed against the risk of autoimmunity due to the self origin of tumors. Whole cell vaccines are one promising immunotherapeutic avenue whereby a myriad of tumor antigens are introduced in an immunogenic context with the aim of eliciting tumor rejection. Despite the possibility collateral damage to healthy tissues, cancer immunotherapy can be designed such that off target autoimmunity remains limited in scope and severity or completely non-existent. Here we provide an immunological basis for reconciling the safety of cancer vaccines, focusing on tumor endothelial cell vaccines, by discussing the following topics: (a) Antigenic differences between neoplastic and healthy tissues that can be leveraged in cancer vaccine design; (b) The layers of tolerance that control T cell responses directed against antigens expressed in healthy tissues and tumors; and, (c) The hierarchy of antigenic epitope selection and display in response to whole cell vaccines, and how antigen processing and presentation can afford a degree of selectivity against tumors. We conclude with an example of early clinical data utilizing ValloVax™, an immunogenic placental endothelial cell vaccine that is being advanced to target the tumor endothelium of diverse cancers, and we report on the safety and efficacy of ValloVax™ for inducing immunity against tumor endothelial antigens.


Assuntos
Antígenos de Neoplasias/metabolismo , Células Endoteliais/metabolismo , Terapia de Alvo Molecular , Vacinas Anticâncer/efeitos adversos , Vacinas Anticâncer/imunologia , Humanos , Neoplasias/irrigação sanguínea , Neoplasias/imunologia , Vacinação/efeitos adversos
12.
Mol Cell Proteomics ; 15(5): 1598-609, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26900162

RESUMO

Precisely knowing the stoichiometry of their components is critical for investigating structure, assembly, and function of macromolecular machines. This has remained a technical challenge in particular for large, hydrophobic membrane-spanning protein complexes. Here, we determined the stoichiometry of a type III secretion system of Salmonella enterica serovar Typhimurium using two complementary protocols of gentle complex purification combined with peptide concatenated standard and synthetic stable isotope-labeled peptide-based mass spectrometry. Bacterial type III secretion systems are cell envelope-spanning effector protein-delivery machines essential for colonization and survival of many Gram-negative pathogens and symbionts. The membrane-embedded core unit of these secretion systems, termed the needle complex, is composed of a base that anchors the machinery to the inner and outer membranes, a hollow filament formed by inner rod and needle subunits that serves as conduit for substrate proteins, and a membrane-embedded export apparatus facilitating substrate translocation. Structural analyses have revealed the stoichiometry of the components of the base, but the stoichiometry of the essential hydrophobic export apparatus components and of the inner rod protein remain unknown. Here, we provide evidence that the export apparatus of type III secretion systems contains five SpaP, one SpaQ, one SpaR, and one SpaS. We confirmed that the previously suggested stoichiometry of nine InvA is valid for assembled needle complexes and describe a loose association of InvA with other needle complex components that may reflect its function. Furthermore, we present evidence that not more than six PrgJ form the inner rod of the needle complex. Providing this structural information will facilitate efforts to obtain an atomic view of type III secretion systems and foster our understanding of the function of these and related flagellar machines. Given that other virulence-associated bacterial secretion systems are similar in their overall buildup and complexity, the presented approach may also enable their stoichiometry elucidation.


Assuntos
Peptídeos/química , Proteômica/métodos , Salmonella typhimurium/metabolismo , Sistemas de Secreção Tipo III/química , Marcação por Isótopo/métodos , Espectrometria de Massas , Modelos Moleculares , Multimerização Proteica , Salmonella typhimurium/química
13.
J Transl Med ; 13: 340, 2015 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-26510973

RESUMO

Angiogenesis is essential for the growth and metastasis of solid tumors. The tumor endothelium exists in a state of chronic activation and proliferation, fueled by the tumor milieu where angiogenic mediators are aberrantly over-expressed. Uncontrolled tumor growth, immune evasion, and therapeutic resistance are all driven by the dysregulated and constitutive angiogenesis occurring in the vasculature. Accordingly, great efforts have been dedicated toward identifying molecular signatures of this pathological angiogenesis in order to devise selective tumor endothelium targeting therapies while minimizing potential autoimmunity against physiologically normal endothelium. Vaccination with angiogenic antigens to generate cellular and/or humoral immunity against the tumor endothelium has proven to be a promising strategy for inhibiting or normalizing tumor angiogenesis and reducing cancer growth. Here we review tumor endothelium vaccines developed to date including active immunization strategies using specific tumor endothelium-associated antigens and whole endothelial cell-based vaccines designed to elicit immune responses against diverse target antigens. Among the novel therapeutic options, we describe a placenta-derived endothelial cell vaccine, ValloVax™, a polyvalent vaccine that is antigenically similar to proliferating tumor endothelium and is supported by pre-clinical studies to be safe and efficacious against several tumor types.


Assuntos
Vacinas Anticâncer/uso terapêutico , Neoplasias/irrigação sanguínea , Neovascularização Patológica/tratamento farmacológico , Humanos , Neovascularização Patológica/imunologia
14.
Biomed Res Int ; 2015: 865101, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26161418

RESUMO

Patients with certain cancers are treated with curative intent, but for others the results are less favorable and different therapeutic approaches are needed. Early data suggest that new therapies, which modulate immune responses to cancers, may have potential for long-term survival in a proportion of cases. Therefore, it is timely to consider whether metrics generally used to describe the medical value of therapies for patients with common solid tumors remain appropriate for therapies with curative potential. Literature reviews were conducted to define how various stakeholders describe cure in oncology and to identify the endpoints used in clinical trials for selected solid tumors. The results showed that "cure" is described using various terms that can be divided broadly into lack of disease progression, eradication of cancerous cells, and survival. The review of trial endpoints showed frequent use of median overall survival (OS) and progression- and response-related endpoints. Because these endpoints were mainly described in the context of chemotherapies that are not generally curative, they may not adequately capture outcomes of new therapeutic modalities with potential for long-term survival. More appropriate endpoints may include mean OS, cure fraction, and OS rate at landmark time points.


Assuntos
Intervalo Livre de Doença , Determinação de Ponto Final , Neoplasias/epidemiologia , Neoplasias/terapia , Ensaios Clínicos como Assunto , Humanos , Neoplasias/patologia , Resultado do Tratamento
15.
J Transl Med ; 13: 90, 2015 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-25889119

RESUMO

BACKGROUND: While the concept of angiogenesis blockade as a therapeutic intervention for cancer has been repeatedly demonstrated, the full promise of this approach has yet to be realized. Specifically, drugs such as VEGF-blocking antibodies or kinase inhibitors suffer from the drawbacks of resistance development, as well as off-target toxicities. Previous studies have demonstrated feasibility of specifically inducing immunity towards tumor endothelium without consequences of systemic autoimmunity in both animal models and clinical settings. METHOD: Placenta-derived endothelial cells were isolated and pretreated with interferon gamma to enhance immunogenicity. Syngeneic mice received subcutaneous administration of B16 melanoma, 4 T1 mammary carcinoma, and Lewis Lung Carcinoma (LLC), followed by administration of control saline, control placental endothelial cells, and interferon gamma primed endothelial cells (ValloVax™). Tumor volume was quantified. An LLC metastasis model was also established and treated under similar conditions. Furthermore, a safety analysis in non-tumor bearing mice bracketing the proposed clinical dose was conducted. RESULTS: ValloVax™ immunization led to significant reduction of tumor growth and metastasis as compared to administration of non-treated placental endothelial cells. Mitotic inactivation by formalin fixation or irradiation preserved tumor inhibitory activity. Twenty-eight day evaluation of healthy male and female mice immunized with ValloVax™ resulted in no abnormalities or organ toxicities. CONCLUSION: Given the established rationale behind the potential therapeutic benefit of inhibiting tumor angiogenesis as a treatment for cancer, immunization against a variety of endothelial cell antigens may produce the best clinical response, enhancing efficacy and reducing the likelihood of the development of treatment resistance. These data support the clinical evaluation of irradiated ValloVax™ as an anti-angiogenic cancer vaccine.


Assuntos
Células Endoteliais/imunologia , Imunização , Interferon gama/uso terapêutico , Neoplasias/irrigação sanguínea , Neovascularização Patológica/tratamento farmacológico , Placenta/citologia , Animais , Vacinas Anticâncer/efeitos adversos , Vacinas Anticâncer/imunologia , Proliferação de Células , Células Endoteliais/efeitos dos fármacos , Feminino , Imunidade , Interferon gama/efeitos adversos , Interferon gama/farmacologia , Melanoma Experimental/irrigação sanguínea , Melanoma Experimental/imunologia , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Mitose/efeitos dos fármacos , Metástase Neoplásica , Neoplasias/imunologia , Gravidez
16.
Oncol Res Treat ; 38(3): 88-94, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25792079

RESUMO

BACKGROUND: Demonstrating improved overall survival (OS) with new multiple myeloma (MM) treatments is becoming difficult because of extended survival, so progression-free survival (PFS) is commonly used as a surrogate endpoint for OS. We evaluated PFS as a potential surrogate for OS by examining whether observed treatment effects on PFS are positively associated with treatment effects on OS in MM. METHODS: A systematic literature review identified 21 randomized control trials reporting hazard ratios (HRs) for treatment effects on PFS and OS. Pearson's r estimated the relationship between HRs (HRPFS and HROS), and between log-transformed HRs (log(HRPFS) and log(HROS)). R(2) values were estimated from linear regression models of the HR and the log(HR) relationships. Sensitivity and subgroup analyses examined the robustness of the HR findings. RESULTS: Positive correlations were found between HRPFS and HROS (r = 0.82; p < 0.0001) and between log(HRPFS) and log(HROS) (r = 0.80; p < 0.0001). Linear regression models produced R(2) values of 0.67 and 0.63 when regressing HROS on HRPFS, and log(HROS) on log(HRPFS), respectively. Sensitivity analyses supported the HR findings. CONCLUSION: This analysis provides evidence for a positive association between treatment effects on PFS and OS. Studies involving patient level data are necessary to confirm whether PFS is a valid surrogate for OS in MM.


Assuntos
Mieloma Múltiplo/tratamento farmacológico , Antineoplásicos/uso terapêutico , Intervalo Livre de Doença , Mieloma Múltiplo/mortalidade , Ensaios Clínicos Controlados Aleatórios como Assunto , Taxa de Sobrevida , Resultado do Tratamento
17.
Liver Int ; 35(9): 2155-66, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25752327

RESUMO

BACKGROUND & AIMS: Hepatocellular carcinoma (HCC) is the second most common cause of cancer deaths worldwide. The global HCC BRIDGE study was a multiregional, large-scale, longitudinal cohort study undertaken to improve understanding of real-life management of patients with HCC, from diagnosis to death. METHODS: Data were collected retrospectively from January 2005 to September 2012 by chart reviews of eligible patients newly diagnosed with HCC at participating institutions. RESULTS: Forty-two sites in 14 countries contributed final data for 18 031 patients. Asia accounted for 67% of patients, Europe for 20% and North America for 13%. As expected, the most common risk factor was hepatitis C virus in North America, Europe and Japan, and hepatitis B virus in China, South Korea and Taiwan. The most common Barcelona Clinic Liver Cancer stage at diagnosis was C in North America, Europe, China and South Korea, and A in Taiwan and Japan. Across all stages, first HCC treatment was most frequently transarterial chemoembolization in North America, Europe, China and South Korea, percutaneous ethanol injection or radiofrequency ablation in Japan and resection in Taiwan. Survival from first HCC treatment varied significantly by region, with median overall survival not reached for Taiwan and 60, 33, 31, 24 and 23 months for Japan, North America, South Korea, Europe and China respectively (P < 0.0001). CONCLUSIONS: Initial results from the BRIDGE study confirm previously reported regional trends in patient demographic characteristics and HCC risk factors, document the heterogeneity of treatment approaches across regions/countries and underscore the need for earlier HCC diagnosis worldwide.


Assuntos
Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/terapia , Adulto , Idoso , Ásia/epidemiologia , Carcinoma Hepatocelular/virologia , Ablação por Cateter , Gerenciamento Clínico , Embolização Terapêutica , Etanol/administração & dosagem , Europa (Continente)/epidemiologia , Feminino , Hepatite B/complicações , Hepatite C/complicações , Humanos , Neoplasias Hepáticas/virologia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , América do Norte/epidemiologia , Estudos Retrospectivos , Fatores de Risco , Análise de Sobrevida
18.
J Transl Med ; 12: 127, 2014 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-24884532

RESUMO

Interleukin-2 (IL-2) therapy has been demonstrated to induce responses in 10-20% of advanced melanoma and renal cell carcinoma patients, which translates into durable remissions in up to half of the responsers. Unfortunately the use of IL-2 has been associated with severe toxicity and death. It has been previously observed and reported that IL-2 therapy causes a major drop in circulating levels of ascorbic acid (AA). The IL-2 induced toxicity shares many features with sepsis such as capillary leakage, systemic complement activation, and a relatively non-specific rise in inflammatory mediators such as TNF-alpha, C-reactive protein, and in advanced cases organ failure. Animal models and clinical studies have shown rapid depletion of AA in conditions of sepsis and amelioration associated with administration of AA (JTM 9:1-7, 2011). In contrast to other approaches to dealing with IL-2 toxicity, which may also interfere with therapeutic effects, AA possesses the added advantage of having direct antitumor activity through cytotoxic mechanisms and suppression of angiogenesis. Here we present a scientific rationale to support the assessment of intravenous AA as an adjuvant to decrease IL-2 mediated toxicity and possibly increase treatment efficacy.


Assuntos
Ácido Ascórbico/uso terapêutico , Imunoterapia , Interleucina-2/uso terapêutico , Humanos , Infusões Intravenosas , Estresse Oxidativo
19.
J Health Econ Outcomes Res ; 2(1): 75-86, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-37664084

RESUMO

Background: Tyrosine kinase inhibitors (TKIs) have significantly improved survival for patients with chronic myeloid leukemia (CML) but require long-term administration and non-adherence due to regimen requirements has been reported. Objectives: This study sought to identify how much patients value more convenient regimens and the potential impact that regimen may have on medication adherence. Methods: This cross-sectional, six-country study utilized a web-based discrete conjoint experiment (DCE) survey in which participants selected between hypothetical treatments that differed on three attributes: meal requirements/restrictions, frequency of administration, and monthly co-pay, to quantify willingness to pay. Attribute percent importance ratings were derived from a multinomial logit model, and utilities were summed for each product profile to determine the most preferred regimen profile. Additional survey questions asked about attributes perceived to affect adherence and the ease and convenience of participants' current regimen. Results: A total of 318 patients completed the survey; median age 53 years (range 18-87); 43.7% male. Four participants were excluded from the conjoint analysis due to illogical responses. The most important regimen attribute driving preferences was the meal requirement/restriction, which was almost twice as important as dose frequency. The majority of participants preferred the profile of a once a day dosing taken with or without a meal, and estimates of willingness-to-pay helped to quantify this preference. In terms of adherence, the majority of participants perceived that having to fast before and after taking medication would be the most likely reason for missing a dose. Conclusions: The results suggest that patients value the convenience of CML treatments and perceive certain regimen characteristics, particularly meal requirements or restrictions, as likely to affect adherence. It is important for healthcare providers to be aware of the potential impact of treatment convenience on non-adherence and communicate closely with patients to decrease this potential.

20.
Health Qual Life Outcomes ; 10: 66, 2012 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-22694829

RESUMO

BACKGROUND: In an international, randomized Phase III trial ipilimumab demonstrated a significant overall survival benefit in previously treated advanced melanoma patients. This report summarizes health-related quality of life (HRQL) outcomes for ipilimumab with/without gp100 vaccine compared to gp100 alone during the clinical trial's 12 week treatment induction period. METHODS: The Phase III clinical trial (MDX010-20) was a double-blind, fixed dose study in 676 previously treated advanced unresectable stage III or IV melanoma patients. Patients were randomized 3:1:1 to receive either ipilimumab (3 mg/kg q3w x 4 doses) + gp100 (peptide vaccine; 1 mg q3w x 4 doses; ipilimumab plus gp100, n = 403); gp100 vaccine + placebo (gp100 alone, n = 136); or ipilimumab + placebo (ipilimumab alone, n = 137). The European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30) assessed HRQL. Baseline to Week 12 changes in EORTC QLQ-C30 function, global health status, and symptom scores were analyzed for ipilimumab with/without gp100 vaccine compared to gp100 alone. Mean change in scores were categorized "no change" (0-5), "a little" (5-10 points), "moderate" (10-20 points), and "very much" (>20). RESULTS: In the ipilimumab plus gp100 and ipilimumab alone groups, mean changes from baseline to Week 12 generally indicated "no change" or "a little" impairment across EORTC QLQ-C30 global health status, function, and symptom subscales. Significant differences in constipation, favoring ipilimumab, were observed (p < 0.05). For ipilimumab alone arm, subscales with no or a little impairment were physical, emotional, cognitive, social function, global health, nausea, pain, dyspnea, constipation, and diarrhea subscales. For the gp100 alone group, the observed changes were moderate to large for global health, role function, fatigue, and for pain. CONCLUSIONS: Ipilimumab with/without gp100 vaccine does not have a significant negative HRQL impact during the treatment induction phase relative to gp100 alone in stage III or IV melanoma patients. TRIAL REGISTRATION: Clinicaltrials.gov identification number NCT00094653.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Antineoplásicos/uso terapêutico , Vacinas Anticâncer/uso terapêutico , Indicadores Básicos de Saúde , Melanoma , Qualidade de Vida , Terapia Combinada , Método Duplo-Cego , Feminino , Humanos , Ipilimumab , Masculino , Melanoma/psicologia , Melanoma/secundário , Melanoma/terapia , Pessoa de Meia-Idade , Estadiamento de Neoplasias
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