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1.
N Engl J Med ; 382(14): 1331-1342, 2020 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-32242358

RESUMO

BACKGROUND: Patients with relapsed or refractory mantle-cell lymphoma who have disease progression during or after the receipt of Bruton's tyrosine kinase (BTK) inhibitor therapy have a poor prognosis. KTE-X19, an anti-CD19 chimeric antigen receptor (CAR) T-cell therapy, may have benefit in patients with relapsed or refractory mantle-cell lymphoma. METHODS: In a multicenter, phase 2 trial, we evaluated KTE-X19 in patients with relapsed or refractory mantle-cell lymphoma. Patients had disease that had relapsed or was refractory after the receipt of up to five previous therapies; all patients had to have received BTK inhibitor therapy previously. Patients underwent leukapheresis and optional bridging therapy, followed by conditioning chemotherapy and a single infusion of KTE-X19 at a dose of 2×106 CAR T cells per kilogram of body weight. The primary end point was the percentage of patients with an objective response (complete or partial response) as assessed by an independent radiologic review committee according to the Lugano classification. Per the protocol, the primary efficacy analysis was to be conducted after 60 patients had been treated and followed for 7 months. RESULTS: A total of 74 patients were enrolled. KTE-X19 was manufactured for 71 patients and administered to 68. The primary efficacy analysis showed that 93% (95% confidence interval [CI], 84 to 98) of the 60 patients in the primary efficacy analysis had an objective response; 67% (95% CI, 53 to 78) had a complete response. In an intention-to-treat analysis involving all 74 patients, 85% had an objective response; 59% had a complete response. At a median follow-up of 12.3 months (range, 7.0 to 32.3), 57% of the 60 patients in the primary efficacy analysis were in remission. At 12 months, the estimated progression-free survival and overall survival were 61% and 83%, respectively. Common adverse events of grade 3 or higher were cytopenias (in 94% of the patients) and infections (in 32%). Grade 3 or higher cytokine release syndrome and neurologic events occurred in 15% and 31% of patients, respectively; none were fatal. Two grade 5 infectious adverse events occurred. CONCLUSIONS: KTE-X19 induced durable remissions in a majority of patients with relapsed or refractory mantle-cell lymphoma. The therapy led to serious and life-threatening toxic effects that were consistent with those reported with other CAR T-cell therapies. (Funded by Kite, a Gilead company; ZUMA-2 ClinicalTrials.gov number, NCT02601313.).


Assuntos
Antígenos CD19/uso terapêutico , Imunoterapia Adotiva , Linfoma de Célula do Manto/terapia , Receptores de Antígenos Quiméricos/antagonistas & inibidores , Adulto , Idoso , Antineoplásicos/uso terapêutico , Terapia Combinada , Humanos , Imunoterapia Adotiva/efeitos adversos , Infusões Intravenosas , Leucaférese , Linfoma de Célula do Manto/tratamento farmacológico , Linfoma de Célula do Manto/mortalidade , Pessoa de Meia-Idade , Recidiva , Análise de Sobrevida , Linfócitos T/transplante , Vidarabina/análogos & derivados , Vidarabina/uso terapêutico
2.
Blood ; 138(1): 11-22, 2021 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-33827116

RESUMO

ZUMA-3 is a phase 1/2 study evaluating KTE-X19, an autologous anti-CD19 chimeric antigen receptor (CAR) T-cell therapy, in adult relapsed/refractory (R/R) B-cell acute lymphoblastic leukemia (B-ALL). We report the phase 1 results. After fludarabine-cyclophosphamide lymphodepletion, patients received a single infusion of KTE-X19 at 2 × 106, 1 × 106, or 0.5 × 106 cells per kg. The rate of dose-limiting toxicities (DLTs) within 28 days after KTE-X19 infusion was the primary end point. KTE-X19 was manufactured for 54 enrolled patients and administered to 45 (median age, 46 years; range, 18-77 years). No DLTs occurred in the DLT-evaluable cohort. Grade ≥3 cytokine release syndrome (CRS) and neurologic events (NEs) occurred in 31% and 38% of patients, respectively. To optimize the risk-benefit ratio, revised adverse event (AE) management for CRS and NEs (earlier steroid use for NEs and tocilizumab only for CRS) was evaluated at 1 × 106 cells per kg KTE-X19. In the 9 patients treated under revised AE management, 33% had grade 3 CRS and 11% had grade 3 NEs, with no grade 4 or 5 NEs. The overall complete remission rate correlated with CAR T-cell expansion and was 83% in patients treated with 1 × 106 cells per kg and 69% in all patients. Minimal residual disease was undetectable in all responding patients. At a median follow-up of 22.1 months (range, 7.1-36.1 months), the median duration of remission was 17.6 months (95% confidence interval [CI], 5.8-17.6 months) in patients treated with 1 × 106 cells per kg and 14.5 months (95% CI, 5.8-18.1 months) in all patients. KTE-X19 treatment provided a high response rate and tolerable safety in adults with R/R B-ALL. Phase 2 is ongoing at 1 × 106 cells per kg with revised AE management. This trial is registered at www.clinicaltrials.gov as #NCT02614066.


Assuntos
Antígenos CD19/metabolismo , Imunoterapia Adotiva , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Receptores de Antígenos Quiméricos/uso terapêutico , Adolescente , Adulto , Idoso , Biomarcadores Tumorais/metabolismo , Proliferação de Células , Síndrome da Liberação de Citocina/induzido quimicamente , Intervalo Livre de Doença , Relação Dose-Resposta a Droga , Feminino , Humanos , Imunoterapia Adotiva/efeitos adversos , Mediadores da Inflamação/metabolismo , Masculino , Pessoa de Meia-Idade , Neoplasia Residual/patologia , Resultado do Tratamento , Adulto Jovem
3.
Invest New Drugs ; 29(6): 1420-5, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20661623

RESUMO

PURPOSE: ILX23-7553 (1,25-dihydroxy-16-ene-23-yne vitamin D3) is a vitamin D analogue that was developed to avoid the hypercalcemia that may limit the use of vitamin D as an anti-cancer agent. We performed a phase I study of ILX23-7553 to determine its side-effect profile, pharmacokinetics, and to document any observed antitumor activity. PATIENTS AND METHODS: Adult patients with refractory solid tumors were enrolled. A modified Fibonacci dose escalation scheme was employed. ILX23-7553 was administered orally daily for three consecutive days, and repeated in 7-day cycles. Plasma drug concentrations were assayed by radioimmunoassay and radioreceptor assay. RESULTS: Sixteen patients were enrolled to 10 dose levels ranging from 1.7 to 37.3 µg/m(2)/day. The maximum tested dose was six times higher than the maximally-tolerated dose (MTD) in dogs. Dose-limiting toxicity was not observed. ILX23-7553 concentrations on cycle 1 day 1 of treatment were comparable to concentrations on cycle 2 day 1, suggesting limited accumulation. One patient with adrenal cortical cancer had stable disease for 23 weeks, but no objective responses were observed. CONCLUSIONS: ILX23-7553 was well tolerated at the doses tested, with no evidence of hypercalcemia. The plasma concentrations achieved were approximately 100-fold lower than those associated with tumor growth inhibition in vitro, limiting use of this formulation.


Assuntos
Antineoplásicos/efeitos adversos , Colecalciferol/análogos & derivados , Neoplasias/tratamento farmacológico , Administração Oral , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacocinética , Colecalciferol/administração & dosagem , Colecalciferol/efeitos adversos , Colecalciferol/farmacocinética , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Neoplasias/patologia , Radioimunoensaio , Ensaio Radioligante , Resultado do Tratamento
4.
Cancer Med ; 5(8): 2091-100, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27263488

RESUMO

Hypercalcemia of malignancy (HCM) is a serious metabolic complication whose population-based prevalence has not been quantified. Rates of HCM differ by tumor type, with highest rates reported in multiple myeloma and lowest among colorectal and prostate cancer patients. This analysis estimates HCM prevalence in the US. This retrospective study used the Oncology Services Comprehensive Electronic Records (OSCER) warehouse of electronic health records (EHR) including laboratory values from 569000 patients treated at 565 oncology outpatient sites. OSCER data were projected to the national level by linking EHR to claims data. Cancer patients included were ≥18 years, and had serum calcium (Ca) and albumin (for corrected serum Ca [CSC]) records. Period prevalence was estimated by HCM CTCAE grade, tumor type, and year (2009-2013). Estimates were adjusted to capture patients diagnosed with HCM outside oncology practices based on a subset of patients linkable to office and hospital data. The analysis included 68023 (2009) to 121482 (2013) cancer patients. In 2013, patients with HCM had a median of six Ca tests, 69.7% had chemotherapy, and 34% received bone modifying agents. HCM rates were highest for multiple myeloma patients (7.5% [2012]-10.2% [2010]), lowest for prostate cancer (1.4% [2012]-2.1% [2011]).The estimated adjusted annual prevalence of HCM from 2009 to 2013 was 95441, 96281, 89797, 70158, and 71744, respectively. HCM affected 2.0-2.8% of all cancer patients. EHR data from oncology clinics were critical for this study because these data contain results from laboratory studies (i.e., serum calcium values) that are routinely ordered in that setting. We estimated that the prevalence of HCM in the US in 2013 is 71744, affecting approximately 2% of cancer patients overall. This percentage differs by tumor type and appears to have decreased over the five-year study period.


Assuntos
Hipercalcemia/epidemiologia , Hipercalcemia/etiologia , Neoplasias/complicações , Neoplasias/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Bases de Dados Factuais , Feminino , Humanos , Hipercalcemia/mortalidade , Hipercalcemia/fisiopatologia , Estimativa de Kaplan-Meier , Testes de Função Renal , Masculino , Pessoa de Meia-Idade , Mortalidade , Neoplasias/mortalidade , Neoplasias/patologia , Vigilância da População , Prevalência , Estados Unidos/epidemiologia
5.
Biomedicines ; 3(1): 149-181, 2015 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-28536405

RESUMO

The hepatocyte growth factor (HGF): MET axis is a ligand-mediated receptor tyrosine kinase pathway that is involved in multiple cellular functions, including proliferation, survival, motility, and morphogenesis. Aberrancy in the HGF/MET pathway has been reported in multiple tumor types and is associated with tumor stage and prognosis. Thus, targeting the HGF/MET pathway has become a potential therapeutic strategy in oncology development in the last two decades. A number of novel therapeutic agents-either as therapeutic proteins or small molecules that target the HGF/MET pathway-have been tested in patients with different tumor types in clinical studies. In this review, recent progress in HGF/MET pathway-targeted therapy for cancer treatment, the therapeutic potential of HGF/MET-targeted agents, and challenges in the development of such agents will be discussed.

6.
Cell Cycle ; 14(21): 3434-40, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26467427

RESUMO

PURPOSE: Cancer is a manifestation of aberrant cellular proliferation, and the cell cycle is one of the most successfully drugged targets in oncology. No prior study has been reported that simultaneously targets the 3 principal cell cycle phases populated by proliferating cells--G1, S, and G2/M. METHODS: Temsirolimus (G1 inhibitor), topotecan (S inhibitor), and bortezomib (G2/M inhibitor) were administered in combination to patients with advanced malignancies using a 3+3 dose escalation schedule to assess the safety and establish the maximum tolerated dose (primary endpoints) of this cell cycle targeting approach. An in silico pharmacodynamic model using established effects of each of these agents on the cell cycle was used to validate the regimen and to guide the dosing regimen. RESULTS: Sixty-two subjects were enrolled. The most common adverse events and dose-limiting toxicities were cytopenias, consistent with the cell cycle targeting approach employed. All cytopenias resolved to baseline values upon holding study drug administration. The maximum tolerated dose was temsirolimus 15 mg/kg IV D1, 8, 15; topotecan 2.8 mg/m(2) IV D1, 8; and bortezomib 0.6 mg/m2 IV D1, 4, 8, 11 [DOSAGE ERROR CORRECTED] of a 21-day cycle. In silico modeling suggests the regimen induces cell population shifts from G2/M and S phases to G1 phase and the quiescent G0 phase. Eighteen percent of subjects (11/62) achieved partial response (n = 2, serous ovarian and papillary thyroid) or stable disease for > 6 months (n = 9). CONCLUSION: Combining drugs with inhibitory activity of G1 phase, S phase, and G2/M phase is safe and warrants further evaluation.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Pontos de Checagem da Fase S do Ciclo Celular/efeitos dos fármacos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Bortezomib/administração & dosagem , Simulação por Computador , Progressão da Doença , Intervalo Livre de Doença , Esquema de Medicação , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Modelos Biológicos , Terapia de Alvo Molecular , Neoplasias/enzimologia , Neoplasias/mortalidade , Neoplasias/patologia , Sirolimo/administração & dosagem , Sirolimo/análogos & derivados , Texas , Fatores de Tempo , Topotecan/administração & dosagem , Resultado do Tratamento , Adulto Jovem
7.
J Clin Endocrinol Metab ; 99(9): 3144-52, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24915117

RESUMO

CONTEXT: Hypercalcemia of malignancy (HCM) in patients with advanced cancer is often caused by excessive osteoclast-mediated bone resorption. Patients may not respond to or may relapse after iv bisphosphonate therapy. OBJECTIVE: We investigated whether denosumab, a potent inhibitor of osteoclast-mediated bone resorption, reduces serum calcium in patients with bisphosphonate-refractory HCM. DESIGN, SETTING, AND PARTICIPANTS: In this single-arm international study, participants had serum calcium levels corrected for albumin (CSC) >12.5 mg/dL (3.1 mmol/L) despite bisphosphonates given >7 and ≤30 days before screening. INTERVENTION: Patients received 120 mg sc denosumab on days 1, 8, 15, and 29 and then every 4 weeks. MAIN OUTCOME MEASURES: The primary endpoint was the proportion of patients with CSC ≤11.5 mg/dL (2.9 mmol/L) (response) by day 10. Secondary endpoints included response by visit, duration of response, and the proportion of patients with a complete response (CSC ≤10.8 mg/dL [2.7 mmol/L]) by day 10 and during the study. RESULTS: Patients (N = 33) had solid tumors or hematologic malignancies. By day 10, 21 patients (64%) reached CSC ≤11.5 mg/dL, and 12 patients (33%) reached CSC ≤10.8 mg/dL. During the study, 23 patients (70%) reached CSC ≤11.5 mg/dL, and 21 patients (64%) reached CSC ≤10.8 mg/dL. Estimated median response duration was 104 days. The most common serious adverse events were hypercalcemia worsening (5 patients, 15%) and dyspnea (3 patients, 9%). CONCLUSIONS: In patients with HCM despite recent iv bisphosphonate treatment, denosumab lowered serum calcium in 64% of patients within 10 days, inducing durable responses. Denosumab may offer a new treatment option for HCM.


Assuntos
Anticorpos Monoclonais Humanizados/administração & dosagem , Hipercalcemia/tratamento farmacológico , Hipercalcemia/etiologia , Neoplasias/complicações , Ligante RANK/antagonistas & inibidores , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados/efeitos adversos , Conservadores da Densidade Óssea/administração & dosagem , Reabsorção Óssea/tratamento farmacológico , Reabsorção Óssea/etiologia , Denosumab , Difosfonatos/administração & dosagem , Feminino , Gastroenteropatias/induzido quimicamente , Humanos , Hipofosfatemia/induzido quimicamente , Internacionalidade , Masculino , Pessoa de Meia-Idade , Albumina Sérica/metabolismo , Terapêutica , Adulto Jovem
8.
J Natl Cancer Inst ; 105(18): 1417-20, 2013 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-23990665

RESUMO

Hypercalcemia of malignancy (HCM), caused primarily by tumor-induced bone resorption, may lead to renal failure, coma, and death. Although HCM can be treated with intravenous bisphosphonates, patients may not respond or may relapse on therapy. Denosumab binds the bone resorption mediator RANKL. In this single-arm, open-label, proof-of-concept study, HCM patients with albumin-corrected serum calcium (CSC) levels greater than 12.5mg/dL (Common Terminology Criteria for Adverse Events grade ≥ 3) despite recent intravenous bisphosphonate treatment received subcutaneous denosumab on days 1, 8, 15, and 29, and then every 4 weeks. The primary endpoint was the proportion of patients with CSC 11.5mg/dL or less (grade ≤ 1) within 10 days of denosumab initiation. In a prespecified interim analysis, 15 patients received denosumab (median CSC = 13.6 mg/dL). Time to response and response duration were analyzed with Kaplan-Meier methods. All statistical tests were two-sided. By day 10, 12 patients (80%; 95% exact confidence interval [CI] = 52% to 96%) responded (CSC ≤ 11.5mg/dL); median response duration was 26 days. Ten patients (67%; 95% exact CI = 38% to 88%) had complete responses (CSC ≤ 10.8 mg/dL) by day 10. Denosumab may offer a new treatment option for HCM. Clinicaltrials.gov identifier: NCT00896454.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Conservadores da Densidade Óssea/uso terapêutico , Neoplasias Ósseas/complicações , Difosfonatos/uso terapêutico , Hipercalcemia/tratamento farmacológico , Hipercalcemia/etiologia , Adulto , Idoso , Anticorpos Monoclonais Humanizados/administração & dosagem , Neoplasias Ósseas/metabolismo , Denosumab , Esquema de Medicação , Feminino , Humanos , Incidência , Injeções Subcutâneas , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Ligante RANK/efeitos dos fármacos , Ligante RANK/metabolismo , Recidiva , Resultado do Tratamento
9.
J Clin Oncol ; 30(21): 2684-90, 2012 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-22689801

RESUMO

PURPOSE: RECIST is used to quantify tumor changes during exposure to anticancer agents. Responses are categorized as complete response (CR), partial response (PR), stable disease (SD), or progressive disease (PD). Clinical trials dictate a patient's management options based on the category into which his or her response falls. However, the association between response and survival is not well studied in the early trial setting. PATIENTS AND METHODS: To study the correlation between response as quantified by RECIST and overall survival (OS, the gold-standard survival outcome), we analyzed 570 participants of 24 phase I trials conducted between October 2004 and May 2009, of whom 468 had quantifiable changes in tumor size. Analyses of Kaplan-Meier estimates of OS by response and null Martingale residuals of Cox models were the primary outcome measures. All analyses are landmark analyses. RESULTS: Kaplan-Meier analyses revealed strong associations between change in tumor size by RECIST and survival (P = 4.5 × 10(-6) to < 1 × 10(-8)). The relationship was found to be near-linear (R(2) = 0.75 to 0.92) and confirmed by the residual analyses. No clear inflection points were found to exist in the relationship between tumor size changes and survival. CONCLUSION: RECIST quantification of response correlates with survival, validating RECIST's use in phase I trials. However, the lack of apparent boundary values in the relationship between change in tumor size and OS demonstrates the arbitrary nature of the CR/PR/SD/PD categories and questions emphasis placed on this categorization scheme. Describing tumor responses as a continuous variable may be more informative than reporting categoric responses when evaluating novel anticancer therapies.


Assuntos
Antineoplásicos/uso terapêutico , Ensaios Clínicos Fase I como Assunto , Terapia de Alvo Molecular , Neoplasias/mortalidade , Neoplasias/patologia , Carga Tumoral/efeitos dos fármacos , Humanos , Estimativa de Kaplan-Meier , Modelos Lineares , Neoplasias/tratamento farmacológico , Modelos de Riscos Proporcionais , Indução de Remissão , Texas/epidemiologia , Resultado do Tratamento
10.
Clin Cancer Res ; 17(22): 7174-82, 2011 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-21933889

RESUMO

BACKGROUND: GLIPR1 is upregulated by p53 in prostate cancer cells and has preclinical antitumor activity. A phase I clinical trial was conducted to evaluate the safety and activity of the neoadjuvant intraprostatic injection of GLIPR1 expressing adenovirus for intermediate or high-risk localized prostate cancer before radical prostatectomy (RP). METHODS: Eligible men had localized prostate cancer (T1-T2c) with Gleason score greater than or equal to 7 or prostate-specific antigen 10 ng/mL or more and were candidates for RP. Patients received the adenoviral vector expressing the GLIPR1 gene by a single injection into the prostate followed four weeks later by RP. Six viral particle (vp) dose levels were evaluated: 10(10), 5 × 10(10), 10(11), 5 × 10(11), 10(12), and 5 × 10(12) vp. RESULTS: Nineteen patients with a median age of 64 years were recruited. Nine men had T1c, 4 had T2a, and 3 had T2b and T2c clinical stage. Toxicities included urinary tract infection (n = 3), flu-like syndrome (n = 3), fever (n = 1), dysuria (n = 1), and photophobia (n = 1). Laboratory toxicities were grade 1 elevated AST/ALT (n = 1) and elevations of PTT (n = 3, with 1 proven to be lupus anticoagulant). No pathologic complete remission was seen. Morphologic cytotoxic activity, induction of apoptosis, and nuclear p27(Kip1) upregulation were observed. Peripheral blood CD8(+), CD4(+), and CD3(+) T-lymphocytes were increased, with upregulation of their HLA-DR expression and elevations of serum IL-12. CONCLUSIONS: The intraprostatic administration of GLIPR1 tumor suppressor gene expressed by an adenoviral vector was safe in men, with localized intermediate or high-risk prostate cancer preceding RP. Preliminary evidence of biologic antitumor activity and systemic immune response was documented.


Assuntos
Genes Supressores , Terapia Genética/métodos , Proteínas de Neoplasias/genética , Proteínas do Tecido Nervoso/genética , Neoplasias da Próstata/terapia , Adenoviridae/genética , Idoso , Técnicas de Transferência de Genes , Vetores Genéticos , Humanos , Masculino , Proteínas de Membrana , Pessoa de Meia-Idade , Terapia Neoadjuvante , Prostatectomia , Neoplasias da Próstata/patologia , Neoplasias da Próstata/cirurgia , Risco
11.
Clin Cancer Res ; 16(17): 4305-7, 2010 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-20736331

RESUMO

Food can alter the bioavailability of orally administered drugs. Description of food effects in product labels and information about administration in relation to food are influenced by a variety of factors. Because food effects can change drug efficacy and toxicity, it is important that physicians and patients be aware of them.


Assuntos
Antineoplásicos/administração & dosagem , Rotulagem de Medicamentos/normas , Interações Alimento-Droga , Preparações Farmacêuticas/administração & dosagem , Administração Oral , Antineoplásicos/farmacocinética , Área Sob a Curva , Disponibilidade Biológica , Jejum , Alimentos , Humanos , Absorção Intestinal
12.
Clin Cancer Res ; 16(4): 1289-97, 2010 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-20145187

RESUMO

PURPOSE: To safely assess new drugs, cancer patients in initial cohorts of phase I oncology studies receive low drug doses. Doses are successively increased until the maximum tolerated dose (MTD) is determined. Because traditional chemotherapy is often more effective near the MTD, ethical concerns have been raised about administration of low drug doses to phase I patients. However, a substantial portion of oncology trials now investigate targeted agents, which may have different dose-response relationships than cytotoxic chemotherapies. EXPERIMENTAL DESIGN: Twenty-four consecutive trials treating 683 patients between October 1, 2004, and June 30, 2008, at MD Anderson Cancer Center were analyzed. Patients were assigned to a low-dose (or=75% MTD) group, and groups were compared for response rate, time-to-treatment failure, progression-free survival, overall survival, and toxicity. To remove negatively biasing data from the high-dose group, in a second analysis, patients treated above the MTD were excluded (high-dose group, 75-100% MTD). Of the 683 patients, 97.7% received targeted agents. RESULTS: Even when excluding patients above the MTD, there was an early trend favoring the low- versus high-dose group in time-to-treatment failure, with 32.9% versus 25.2% of patients on therapy at 3 months (P = 0.08). In addition, the low-dose group fared at least as well as the other groups in all other outcomes, including response rate, progression-free survival, overall survival, and toxicity. CONCLUSIONS: These data may help alleviate concerns that patients who receive low drug doses on contemporary phase I oncology trials fare worse and suggest targeted agents may have different dose-response relationships than cytotoxic chemotherapies.


Assuntos
Antineoplásicos/administração & dosagem , Ensaios Clínicos Fase I como Assunto , Sistemas de Liberação de Medicamentos , Neoplasias/tratamento farmacológico , Antineoplásicos/efeitos adversos , Intervalo Livre de Doença , Relação Dose-Resposta a Droga , Humanos , Dose Máxima Tolerável , Neoplasias/mortalidade , Prognóstico , Fatores de Tempo , Resultado do Tratamento
16.
Proc Natl Acad Sci U S A ; 101(1): 111-6, 2004 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-14684834

RESUMO

Atomic resolution structures of proteins indicate that the core is typically well packed, suggesting a densely connected network of interactions between amino acid residues. The combinatorial complexity of energetic interactions in such a network could be enormous, a problem that limits our ability to relate structure and function. Here, we report a case study of the complexity of amino acid interactions in a localized region within the core of the GFP, a particularly stable and tightly packed molecule. Mutations at three sites within the chromophore-binding pocket display an overlapping pattern of conformational change and are thermodynamically coupled, seemingly consistent with the dense network model. However, crystallographic and energetic analyses of coupling between mutations paint a different picture; pairs of mutations couple through independent "hotspots" in the region of structural overlap. The data indicate that, even in highly stable proteins, the core contains sufficient plasticity in packing to uncouple high-order energetic interactions of residues, a property that is likely general in proteins.


Assuntos
Aminoácidos/química , Proteínas/química , Sítios de Ligação , Fenômenos Biofísicos , Biofísica , Proteínas de Fluorescência Verde , Proteínas Luminescentes/química , Proteínas Luminescentes/genética , Modelos Moleculares , Mutagênese Sítio-Dirigida , Conformação Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Termodinâmica
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