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1.
Eur J Cancer ; 196: 113455, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38029480

RESUMO

BACKGROUND: BRAF+MEK inhibitors extend life expectancy of patients with BRAFV600 mutant advanced melanoma. Acquired resistance limits duration of benefit, but preclinical and case studies suggest intermittent dosing could overcome this limitation. INTERIM was a phase 2 trial evaluating an intermittent dosing regimen. METHODS: Patients with BRAFV600 mutant advanced melanoma due to start dabrafenib+trametinib were randomised to receive either continuous (CONT), or intermittent (INT; dabrafenib d1-21, trametinib d1-14 every 28 days) dosing. A composite primary endpoint included progression-free survival (PFS) and quality of life (QoL). Secondary endpoints included response rate (ORR), overall survival (OS) and adverse events (AEs). Mutant BRAFV600E ctDNA was measured by droplet digital PCR (ddPCR), using mutant allele frequency of > 1 % as the detection threshold. RESULTS: 79 patients (39 INT, 40 CONT) were recruited; median age 67 years, 65 % AJCC (7th ed) stage IV M1c, 29 % had brain metastases. With 19 months median follow-up, INT was inferior in all efficacy measures: median PFS 8.5 vs 10.7mo (HR 1.39, 95 %CI 0.79-2.45, p = 0.255); median OS 18.1mo vs not reached (HR 1.69, 95 %CI 0.87-3.28, p = 0.121), ORR 57 % vs 77 %. INT patients experienced fewer treatment-related AEs (76 % vs 88 %), but more grade > 3 AEs (53 % vs 42 %). QoL favoured CONT. Detection of BRAFV600E ctDNA prior to treatment correlated with worse OS (HR 2.55, 95 %CI 1.25-5.21, p = 0.01) in both arms. A change to undetected during treatment did not significantly predict better OS. CONCLUSION: INTERIM findings are consistent with other recent clinical trials reporting that intermittent dosing does not improve efficacy of BRAF+MEK inhibitors.


Assuntos
Melanoma , Neoplasias Cutâneas , Humanos , Idoso , Melanoma/tratamento farmacológico , Melanoma/genética , Melanoma/patologia , Proteínas Proto-Oncogênicas B-raf/genética , Qualidade de Vida , Piridonas , Pirimidinonas , Quinases de Proteína Quinase Ativadas por Mitógeno , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Mutação , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia
2.
Pharmacol Rev ; 74(3): 552-599, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35710137

RESUMO

The nitrogen mustards are powerful cytotoxic and lymphoablative agents and have been used for more than 60 years. They are employed in the treatment of cancers, sarcomas, and hematologic malignancies. Cyclophosphamide, the most versatile of the nitrogen mustards, also has a place in stem cell transplantation and the therapy of autoimmune diseases. Adverse effects caused by the nitrogen mustards on the central nervous system, kidney, heart, bladder, and gonads remain important issues. Advances in analytical techniques have facilitated the investigation of the pharmacokinetics of the nitrogen mustards, especially the oxazaphosphorines, which are prodrugs requiring metabolic activation. Enzymes involved in the metabolism of cyclophosphamide and ifosfamide are very polymorphic, but a greater understanding of the pharmacogenomic influences on their activity has not yet translated into a personalized medicine approach. In addition to damaging DNA, the nitrogen mustards can act through other mechanisms, such as antiangiogenesis and immunomodulation. The immunomodulatory properties of cyclophosphamide are an area of current exploration. In particular, cyclophosphamide decreases the number and activity of regulatory T cells, and the interaction between cyclophosphamide and the intestinal microbiome is now recognized as an important factor. New derivatives of the nitrogen mustards continue to be assessed. Oxazaphosphorine analogs have been synthesized in attempts to both improve efficacy and reduce toxicity, with varying degrees of success. Combinations of the nitrogen mustards with monoclonal antibodies and small-molecule targeted agents are being evaluated. SIGNIFICANCE STATEMENT: The nitrogen mustards are important, well-established therapeutic agents that are used to treat a variety of diseases. Their role is continuing to evolve.


Assuntos
Antineoplásicos , Neoplasias , Compostos de Mostarda Nitrogenada , Antineoplásicos/efeitos adversos , Ciclofosfamida/uso terapêutico , Humanos , Neoplasias/tratamento farmacológico , Nitrogênio/uso terapêutico , Compostos de Mostarda Nitrogenada/uso terapêutico
3.
J Clin Oncol ; 40(22): 2468-2478, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35298280

RESUMO

PURPOSE: Survival in stage I seminoma is almost 100%. Computed tomography (CT) surveillance is an international standard of care, avoiding adjuvant therapy. In this young population, minimizing irradiation is vital. The Trial of Imaging and Surveillance in Seminoma Testis (TRISST) assessed whether magnetic resonance images (MRIs) or a reduced scan schedule could be used without an unacceptable increase in advanced relapses. METHODS: A phase III, noninferiority, factorial trial. Eligible participants had undergone orchiectomy for stage I seminoma with no adjuvant therapy planned. Random assignment was to seven CTs (6, 12, 18, 24, 36, 48, and 60 months); seven MRIs (same schedule); three CTs (6, 18, and 36 months); or three MRIs. The primary outcome was 6-year incidence of Royal Marsden Hospital stage ≥ IIC relapse (> 5 cm), aiming to exclude increases ≥ 5.7% (from 5.7% to 11.4%) with MRI (v CT) or three scans (v 7); target N = 660, all contributing to both comparisons. Secondary outcomes include relapse ≥ 3 cm, disease-free survival, and overall survival. Intention-to-treat and per-protocol analyses were performed. RESULTS: Six hundred sixty-nine patients enrolled (35 UK centers, 2008-2014); mean tumor size was 2.9 cm, and 358 (54%) were low risk (< 4 cm, no rete testis invasion). With a median follow-up of 72 months, 82 (12%) relapsed. Stage ≥ IIC relapse was rare (10 events). Although statistically noninferior, more events occurred with three scans (nine, 2.8%) versus seven scans (one, 0.3%): 2.5% absolute increase, 90% CI (1.0 to 4.1). Only 4/9 could have potentially been detected earlier with seven scans. Noninferiority of MRI versus CT was also shown; fewer events occurred with MRI (two [0.6%] v eight [2.6%]), 1.9% decrease (-3.5 to -0.3). Per-protocol analyses confirmed noninferiority. Five-year survival was 99%, with no tumor-related deaths. CONCLUSION: Surveillance is a safe management approach-advanced relapse is rare, salvage treatment successful, and outcomes excellent, regardless of imaging frequency or modality. MRI can be recommended to reduce irradiation; and no adverse impact on long-term outcomes was seen with a reduced schedule.


Assuntos
Seminoma , Neoplasias Testiculares , Quimioterapia Adjuvante , Seguimentos , Humanos , Masculino , Recidiva Local de Neoplasia/tratamento farmacológico , Estadiamento de Neoplasias , Orquiectomia , Seminoma/tratamento farmacológico , Seminoma/terapia , Neoplasias Testiculares/diagnóstico por imagem , Neoplasias Testiculares/cirurgia
4.
Cells ; 11(1)2021 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-35011579

RESUMO

The modulation of subpopulations of pro-angiogenic monocytes (VEGFR-1+CD14 and Tie2+CD14) was analyzed in an ancillary study from the prospective PazopanIb versus Sunitinib patient preferenCE Study (PISCES) (NCT01064310), where metastatic renal cell carcinoma (mRCC) patients were treated with two anti-angiogenic drugs, either sunitinib or pazopanib. Blood samples from 86 patients were collected prospectively at baseline (T1), and at 10 weeks (T2) and 20 weeks (T3) after starting anti-angiogenic therapy. Various subpopulations of myeloid cells (monocytes, VEGFR-1+CD14 and Tie2+CD14 cells) decreased during treatment. When patients were divided into two subgroups with a decrease (defined as a >20% reduction from baseline value) (group 1) or not (group 2) at T3 for VEGFR-1+CD14 cells, group 1 patients presented a median PFS and OS of 24 months and 37 months, respectively, compared with a median PFS of 9 months (p = 0.032) and a median OS of 16 months (p = 0.033) in group 2 patients. The reduction in Tie2+CD14 at T3 predicted a benefit in OS at 18 months after therapy (p = 0.04). In conclusion, in this prospective clinical trial, a significant decrease in subpopulations of pro-angiogenic monocytes was associated with clinical response to anti-angiogenic drugs in patients with mRCC.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Carcinoma de Células Renais/irrigação sanguínea , Carcinoma de Células Renais/tratamento farmacológico , Neoplasias Renais/irrigação sanguínea , Neoplasias Renais/tratamento farmacológico , Monócitos/patologia , Neovascularização Patológica/tratamento farmacológico , Inibidores da Angiogênese/farmacologia , Animais , Antígenos CD/metabolismo , Carcinoma de Células Renais/sangue , Carcinoma de Células Renais/patologia , Modelos Animais de Doenças , Humanos , Neoplasias Renais/sangue , Neoplasias Renais/patologia , Camundongos Endogâmicos BALB C , Células Mieloides/efeitos dos fármacos , Células Mieloides/patologia , Metástase Neoplásica , Sunitinibe/farmacologia , Sunitinibe/uso terapêutico , Resultado do Tratamento , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/metabolismo
6.
Cancer Med ; 5(7): 1436-43, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27118102

RESUMO

The therapeutic landscape for advanced melanoma has recently been transformed by several novel agents (immune checkpoint inhibitors and molecular-targeted agents). The prospective, multi-site, observational study IMAGE (ipilimumab: management of advanced melanoma in real practice) included a retrospective cohort to describe real-world treatment prior to approval of the immune checkpoint inhibitor ipilimumab. This retrospective cohort of patients, who started second-line/subsequent treatment (index therapy) for advanced melanoma within 3 years before ipilimumab approval, was selected randomly by chart review. Collected data included treatment history, patient outcomes, and healthcare resource utilization. All patients had ≥1 year of follow-up data. This analysis included 177 patients from Europe (69%) and North America (31%). The most common index therapies (used alone or in combination) were fotemustine (23%), dacarbazine (21%), temozolomide (14%), and platinum-based chemotherapy (14%). Most patients (89%) discontinued index treatment during the study period; the most common reason was disease progression (59%). Among patients with tumor assessment (153/177; 86%), 2% had complete response, 5% had partial response, and 12% had stable disease on last tumor assessment. At 1-year study follow-up, median progression-free survival was 2.6 months (95% confidence interval [CI], 2.1-2.9) and median overall survival was 8.8 months (95% CI, 6.5-9.7). During follow-up, 95% of the patients had healthcare visits for advanced melanoma, 74% of whom were hospitalized or admitted to a hospice facility. These results provide insights into patient care with advanced melanoma in the era before ipilimumab and may serve as a benchmark for new agents in future real-world studies.


Assuntos
Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Ipilimumab/uso terapêutico , Melanoma/tratamento farmacológico , Melanoma/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Comorbidade , Feminino , Humanos , Ipilimumab/administração & dosagem , Ipilimumab/efeitos adversos , Masculino , Melanoma/mortalidade , Pessoa de Meia-Idade , Terapia de Alvo Molecular , Metástase Neoplásica , Estadiamento de Neoplasias , Retratamento , Estudos Retrospectivos , Análise de Sobrevida , Resultado do Tratamento , Adulto Jovem
7.
Br J Cancer ; 114(7): 723-30, 2016 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-27002934

RESUMO

BACKGROUND: Rucaparib is an orally available potent selective small-molecule inhibitor of poly(ADP-ribose) polymerase (PARP) 1 and 2. Rucaparib induces synthetic lethality in cancer cells defective in the homologous recombination repair pathway including BRCA-1/2. We investigated the efficacy and safety of single-agent rucaparib in germline (g) BRCA mutation carriers with advanced breast and ovarian cancers. METHODS: Phase II, open-label, multicentre trial of rucaparib in proven BRCA-1/2 mutation carriers with advanced breast and or ovarian cancer, WHO PS 0-1 and normal organ function. Intravenous (i.v.) and subsequently oral rucaparib were assessed, using a range of dosing schedules, to determine the safety, tolerability, dose-limiting toxic effects and pharmacodynamic (PD) and pharmacokinetic (PK) profiles. RESULTS: Rucaparib was well tolerated in patients up to doses of 480 mg per day and is a potent inhibitor of PARP, with sustained inhibition ⩾24 h after single doses. The i.v. rucaparib (intermittent dosing schedule) resulted in an objective response rate (ORR) of only 2% but with 41% (18 out of 44) patients achieved stable disease for ⩾12 weeks and 3 patients maintaining disease stabilisation for >52 weeks. The ORR for oral rucaparib (across all six dose levels) was 15%. In the oral cohorts, 81% (22 out of 27) of the patients had ovarian cancer and 12 out of 13, who were dosed continuously, achieved RECIST complete response/partial response (CR/PR) or stable disease (SD) ⩾12 weeks, with a median duration of response of 179 days (range 84-567 days). CONCLUSIONS: Rucaparib is well tolerated and results in high levels of PARP inhibition in surrogate tissues even at the lowest dose levels. Rucaparib is active in gBRCA-mutant ovarian cancer and this activity correlates with platinum-free interval. The key lessons learned from this study is that continuous rucaparib dosing is required for optimal response, the recommended phase 2 dose (RP2D) for continuous oral scheduling has not been established and requires further exploration and, thirdly, the use of a PD biomarker to evaluate dose-response has its limitations.


Assuntos
Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias da Mama/tratamento farmacológico , Mutação em Linhagem Germinativa/genética , Indóis/uso terapêutico , Neoplasias Ovarianas/tratamento farmacológico , Adulto , Idoso , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Estudos de Coortes , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Seguimentos , Heterozigoto , Humanos , Indóis/farmacocinética , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Inibidores de Poli(ADP-Ribose) Polimerases/farmacocinética , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Prognóstico , Distribuição Tecidual , Adulto Jovem
8.
Breast Cancer Res Treat ; 122(3): 787-94, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20559708

RESUMO

To compare the long-term outcome of women with primary or locally advanced breast cancer randomised to receive either doxorubicin and cyclophosphamide (AC) or doxorubicin and docetaxel (AD) as primary chemotherapy. Eligible patients with histologic-proven breast cancer with primary tumours > or = 3 cm, inflammatory or locally advanced disease, and no evidence of distant metastases, were randomised to receive a maximum of 6 cycles of either doxorubicin (60 mg/m(2)) plus cyclophosphamide (600 mg/m(2)) i/v or doxorubicin (50 mg/m(2)) plus docetaxel (75 mg/m(2)) i/v every 3 weeks, followed by surgery on completion of chemotherapy. Clinical and pathologic responses have previously been reported. Time to relapse, site of relapse, and all-cause mortality were recorded. This updated analysis compares long-term disease-free (DFS) and overall survival (OS) using stratified log rank methods. A total of 363 patients were randomised to AC (n = 181) or AD (n = 182). A complete pathologic response was observed in 16% for AC and 12% for AD (P = 0.43). The number of patients with positive axillary nodes at surgery with AC was 61% and AD 66% (P = 0.36). At a median follow-up of 99 months there is no significant difference between the two groups for DFS (P = 0.20) and OS (P = 0.24). Deaths were due to metastatic breast cancer in 96% of patients. Our data do not support a clinical benefit for simultaneous administration of AD compared with AC. However, the data do not exclude a smaller benefit than the study was powered to detect and are consistent with an increase in both disease-free and overall survival of about 5% for AD compared with AC. Outcome is consistent with the pathologic complete response following surgery.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Adulto , Idoso , Neoplasias da Mama/patologia , Ciclofosfamida/administração & dosagem , Docetaxel , Doxorrubicina/administração & dosagem , Feminino , Seguimentos , Humanos , Linfonodos/patologia , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Taxa de Sobrevida , Taxoides/administração & dosagem , Resultado do Tratamento
9.
J Chromatogr B Analyt Technol Biomed Life Sci ; 846(1-2): 341-5, 2007 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-16962394

RESUMO

A reversed phase high-performance liquid chromatographic (HPLC) method with UV detection was developed for the simultaneous determination of imatinib (Gleevec, Glivec, STI571) and AMN107 in cultured tumour cells, using clozapine as an internal standard. The compounds of interest were extracted by liquid-liquid extraction using TOXI-TUBES((R)) A extraction tubes. Chromatographic separation was performed on a Phenomenex Gemini C18 reversed phase column (150 mm x 2.0 mm, 5 microm particle size), using a mixture of 65% CH(3)OH (methanol) and 35% NH(4)Ac (Ammonium acetate) buffer (20mM, pH 10). Separation was achieved under isocratic conditions at a flow rate of 0.5 ml/min. Imatinib, clozapine and AMN107 are detected by UV detection at 260 nm. Calibration curves were linear from 50 to 7500 ng/ml with correlation coefficients (r(2)) better than 0.998. The limit of quantitation (LOD) was 50 ng/ml. The method has been successfully applied to a cellular kinetics study.


Assuntos
Antineoplásicos/análise , Cromatografia Líquida de Alta Pressão/métodos , Piperazinas/análise , Pirimidinas/análise , Espectrofotometria Ultravioleta/métodos , Benzamidas , Humanos , Mesilato de Imatinib , Sensibilidade e Especificidade , Células Tumorais Cultivadas
10.
J Gastrointest Cancer ; 38(2-4): 108-14, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-19089662

RESUMO

BACKGROUND: The CA 19-9 tumour marker is increasingly used to monitor response to therapy in patients with pancreatic adenocarcinoma. Serum CA 19-9 levels have also been shown to correlate with survival. However, their role in cholangiocarcinoma is less clear. AIM OF STUDY: To assess the utility of CA 19-9 levels in the management of patients with advanced pancreatic adenocarcinoma or cholangiocarcinoma in routine clinical practice is the aim of the study. METHODS: A retrospective analysis of CA 19-9 values and survival was performed in 26 patients with pancreatic adenocarcinoma receiving gemcitabine and in 18 patients with cholangiocarcinoma. RESULTS: Patients with advanced pancreatic adenocarcinoma receiving gemcitabine who experienced a decrease of > or = 20% in CA 19-9 concentration had a median survival of 13.9+ months (range 4.2-23.5) compared to 7.6+ months (range 4.0-14.7) in those without such a change (p = 0.0109). In patients with advanced cholangiocarcinoma, the median survival was longest in those with a baseline CA 19-9 level of less than 1,000 U/ml; 11.8 months (range 1.0-41.4) vs 6.2 months (range 3.1-9.4; p = 0.0075). CONCLUSIONS: The CA 19-9 concentration has a valuable role in predicting outcome in patients with pancreatic adenocarcinoma and cholangiocarcinoma. It is helpful in guiding therapy and should be used accordingly in oncology practice.


Assuntos
Adenocarcinoma/mortalidade , Neoplasias dos Ductos Biliares/mortalidade , Antígeno CA-19-9/sangue , Colangiocarcinoma/mortalidade , Neoplasias Pancreáticas/mortalidade , Adenocarcinoma/sangue , Adenocarcinoma/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Antimetabólitos Antineoplásicos/uso terapêutico , Neoplasias dos Ductos Biliares/sangue , Neoplasias dos Ductos Biliares/tratamento farmacológico , Ductos Biliares Intra-Hepáticos/patologia , Biomarcadores Tumorais/sangue , Colangiocarcinoma/sangue , Colangiocarcinoma/tratamento farmacológico , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Pancreáticas/sangue , Neoplasias Pancreáticas/tratamento farmacológico , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento , Gencitabina
11.
J Pharm Pharmacol ; 58(8): 1063-6, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16872552

RESUMO

The signal transduction inhibitor imatinib is one of the latest breakthroughs in cancer pharmacotherapy. It is administered orally over prolonged periods of time for the treatment of gastro-intestinal stromal tumours. Routine therapeutic drug monitoring of blood plasma versus red blood cells over several years by liquid chromatography coupled tandem mass spectrometry has high-lighted a very intriguing phenomenon. Imatinib plasma availability decreases dramatically owing to a significant shift in the partition ratio of red blood cells versus plasma. The shift is enforced by combination with everolimus, another signal transduction inhibitor. These data warrant routine erythrocyte versus plasma monitoring to prevent unexpected alterations in drug efficacy during long-term treatment.


Assuntos
Antineoplásicos/sangue , Eritrócitos/metabolismo , Imunossupressores/farmacologia , Piperazinas/sangue , Pirimidinas/sangue , Sirolimo/análogos & derivados , Benzamidas , Resistencia a Medicamentos Antineoplásicos , Eritrócitos/efeitos dos fármacos , Everolimo , Tumores do Estroma Gastrointestinal/metabolismo , Humanos , Mesilato de Imatinib , Técnicas In Vitro , Espectrometria de Massas , Plasma/química , Plasma/metabolismo , Sirolimo/farmacologia , Neoplasias Gástricas/metabolismo
12.
J Sep Sci ; 29(3): 453-9, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16544888

RESUMO

The analysis of the signal transduction inhibitor imatinib in patient tumour tissue using LC and MS/MS is described. The anticancer agent is eluted over RP-C18 within 2 mm together with its internal standard STI571-d8. Calibration curves were prepared in red blood cells (RBC). For quantitative isolation of the RBC, measurement of sediment was applied. There were no indications of signal suppression by substances originating in the biological matrix. The limit of determination in tumour tissue was in the range of those recorded for RBC and plasma. The assay is selective and sensitive, with its robustness favouring the experimental application in clinical oncology and its routine use in animal experiments. The LOD was 4.5 ng per gram in tumour tissue.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas/métodos , Neoplasias/metabolismo , Piperazinas/análise , Pirimidinas/análise , Animais , Antineoplásicos/análise , Antineoplásicos/química , Antineoplásicos/farmacocinética , Benzamidas , Calibragem , Eritrócitos/metabolismo , Humanos , Mesilato de Imatinib , Estrutura Molecular , Piperazinas/sangue , Piperazinas/química , Piperazinas/farmacocinética , Pirimidinas/sangue , Pirimidinas/química , Pirimidinas/farmacocinética
13.
Anticancer Drugs ; 16(8): 885-91, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16096438

RESUMO

We have performed in vitro incubations of blood from male and female volunteers with gemcitabine and docetaxel alone, and in combination, at different concentration gradients in order to investigate changes in partition between red blood cells (RBCs), total plasma and the free fraction. After extraction and sample pre-treatment, a validated high-performance liquid chromatography method followed by UV detection was used to determine the concentrations of both drugs in the different blood constituents. The partition ratio [the concentration in the erythrocytes divided by the concentration in plasma (E/P)] was calculated. The partition ratio of docetaxel varied from 0.02 to 1.44 (mean 0.35), reflecting its relatively low affinity for RBCs, probably because of its high plasma protein binding (more than 98%). For gemcitabine, the partition ratio varied from 1 to 5, reflecting a high affinity for RBCs (less than 10% plasma protein bound). The partition ratios of both drugs increased significantly with higher whole-blood concentrations, favoring uptake in the erythrocytes when plasma protein binding is saturated. Combination incubations showed a complex and unexplained interaction between gender and the influence of docetaxel on the partition of gemcitabine. We conclude that the incorporation of drugs into the RBC pool may be important for transportation to tumor tissue and efficacy. In combination, one anti-cancer agent can alter the partition ratios of other anti-cancer agents.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/sangue , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Eritrócitos/metabolismo , Cromatografia Líquida de Alta Pressão , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Docetaxel , Feminino , Humanos , Técnicas In Vitro , Masculino , Taxoides/administração & dosagem , Gencitabina
14.
Anticancer Drugs ; 16(8): 893-5, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16096439

RESUMO

We have performed in vitro incubations of blood from male and female volunteers, smokers and non-smokers, with irinotecan at a gradient of different concentrations in order to investigate changes of partition between red blood cells (RBCs), total plasma and the free fraction. Since irinotecan (CPT-11) is not metabolized in vitro, there is no data available on its active metabolite SN-38. After extraction and sample pre-treatment, a validated high-performance liquid chromatography method followed by fluorescence detection was used to determine the concentration of the drug in the different blood constituents. The partition ratio [the concentration in the erythrocytes divided by the concentration in plasma (E/P)] was calculated. The partition ratio of CPT-11 varied from 0.7 to 2.8, reflecting its relatively high affinity for the erythrocyte, probably because of its only moderate plasma protein binding (65%). The partition ratios increased significantly with higher whole-blood concentrations, favoring uptake in the erythrocytes when plasma protein binding is saturated. No gender difference was detected, but we found relatively more CPT-11 in the erythrocytes of non-smokers compared to smokers. The incorporation of drugs into the RBC pool may be important for transportation to tumor tissue and efficacy. Smoking can have a significant influence on drug partition in the blood.


Assuntos
Antineoplásicos Fitogênicos/sangue , Antineoplásicos Fitogênicos/farmacocinética , Camptotecina/análogos & derivados , Eritrócitos/metabolismo , Fumar/efeitos adversos , Camptotecina/sangue , Camptotecina/farmacocinética , Cromatografia Líquida de Alta Pressão , Feminino , Humanos , Técnicas In Vitro , Irinotecano , Masculino , Distribuição por Sexo , Espectrometria de Fluorescência , Inibidores da Topoisomerase I
15.
J Clin Oncol ; 23(13): 2988-95, 2005 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-15860854

RESUMO

PURPOSE To compare the clinical and pathologic response rates of doxorubicin and cyclophosphamide (AC) with doxorubicin and docetaxel (AD) as primary chemotherapy in women with primary or locally advanced breast cancer. PATIENTS AND METHODS Eligible patients with histologically proven breast cancer with primary tumors >/= 3 cm, inflammatory or locally advanced disease, and no evidence of metastases were randomly assigned to receive a maximum of six cycles of either doxorubicin (60 mg/m(2)) plus cyclophosphamide (600 mg/m(2)) administered intravenously (IV) every 3 weeks or doxorubicin (60 mg/m(2)) plus docetaxel (75 mg/m(2)) IV every 3 weeks, followed by surgery on completion of chemotherapy. Results A total of 363 patients were randomly assigned to AC (n = 180) or AD (n = 183). A complete clinical response was observed in 17% and 20% of patients treated with AC and AD, respectively (P = .42). Overall (complete and partial) clinical response rates for AC and AD were 61% and 70%, respectively (P = .06). There was no significant difference in either the pathologic complete response rates in the breast with AC (24%) and AD (21%; P = .61) or in the number of patients with positive axillary nodes at surgery with AC (61%) and AD (66%; P = .28). At a median follow-up of 32 months, there is no significant difference between the two groups for the number of relapses. CONCLUSION In contrast to the positive results reported for sequential docetaxel after AC as primary chemotherapy of breast cancer, our data do not suggest a benefit for simultaneous AD over AC.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Recidiva Local de Neoplasia , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Ciclofosfamida , Docetaxel , Doxorrubicina/administração & dosagem , Esquema de Medicação , Feminino , Humanos , Infusões Intravenosas , Pessoa de Meia-Idade , Terapia Neoadjuvante , Taxoides/administração & dosagem , Resultado do Tratamento
16.
Clin Chem Lab Med ; 42(11): 1219-27, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15576286

RESUMO

Therapeutic drug monitoring generally focuses on the plasma compartment only. Differentiation between the total plasma concentration and the free fraction (plasma water) has been described for a number of limited drugs. Besides the plasma compartment, blood has also a cellular fraction which has by far the largest theoretical surface and volume for drug transport. It is with anti-cancer drugs that major progress has been made in the study of partition between the largest cellular blood compartment, i.e., erythrocytes, and the plasma compartment. The aim of the present review is to detail the progress made in predicting what a drug does in the body, i.e., pharmacodynamics including toxicity and plasma and/or red blood cell concentration monitoring. Furthermore, techniques generally used in anti-cancer drug monitoring are highlighted. Data for complex Bayesian statistical approaches and population kinetics studies are beyond the scope of this review, since this is generally limited to the plasma compartment only.


Assuntos
Antineoplásicos/farmacologia , Monitoramento de Medicamentos/métodos , Eritrócitos/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Antineoplásicos/sangue , Área Sob a Curva , Cromatografia Líquida , Ensaios Clínicos como Assunto , Eritrócitos/metabolismo , Humanos , Espectrometria de Massas , Monitorização Fisiológica/métodos , Preparações Farmacêuticas
17.
Pharmacol Rev ; 56(4): 549-80, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15602010

RESUMO

Angiogenesis is a hallmark of wound healing, the menstrual cycle, cancer, and various ischemic and inflammatory diseases. A rich variety of pro- and antiangiogenic molecules have already been discovered. Vascular endothelial growth factor (VEGF) is an interesting inducer of angiogenesis and lymphangiogenesis, because it is a highly specific mitogen for endothelial cells. Signal transduction involves binding to tyrosine kinase receptors and results in endothelial cell proliferation, migration, and new vessel formation. In this article, the role of VEGF in physiological and pathological processes is reviewed. We also discuss how modulation of VEGF expression creates new therapeutic possibilities and describe recent developments in this field.


Assuntos
Neovascularização Patológica/fisiopatologia , Neovascularização Fisiológica/fisiologia , Fatores de Crescimento do Endotélio Vascular/fisiologia , Moduladores da Angiogênese/farmacologia , Animais , Humanos , Fatores de Crescimento do Endotélio Vascular/classificação
18.
J Chromatogr A ; 1020(1): 27-34, 2003 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-14661754

RESUMO

An isocratic high-performance liquid chromatographic method coupled to tandem mass spectrometry for the quantification of the revolutionary and promising anticancer agent STI-571 (tradenames Gleevec, Glivec, Imatinib) in blood plasma and red blood cells (RBCs) is described. The method involves measurement of sediment technology for RBCs and a subsequent single protein precipitation step by the addition of acetonitrile to both the RBC isolate and plasma. The sample mixture was centrifuged (10 min, 3600 g), and the supernatant filtered through a HPLC filter (0.45 microm). The analytes of interest, STI-571 and the internal standard [2H8]STI-571 were eluted on a Waters Symmetry C18 column (50x2.1 mm I.D., 3.5 microm particle size) using a methanol-0.05% ammonium acetate (72:28, v/v) mixture. STI-571 and [2H8]STI-571 were detected by electrospray tandem mass spectrometry in the positive mode, and monitored in the multiple reaction monitoring transitions 494>394 and 502<394, respectively. The lower limit of quantitation of STI-571 was 2.1 ng/ml in RBCs and 1.8 ng/ml in plasma. The recovery from both plasma and RBCs was between 65 and 70%. The method proved to be robust, allowing simultaneous quantification of STI-571 in RBCs and plasma with sufficient precision, accuracy and sensitivity and is useful in monitoring the fate of this signal transduction inhibitor in whole blood of cancer patients.


Assuntos
Antineoplásicos/sangue , Eritrócitos/química , Piperazinas/sangue , Pirimidinas/sangue , Espectrometria de Massas por Ionização por Electrospray/métodos , Benzamidas , Humanos , Mesilato de Imatinib , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
19.
Clin Pharmacokinet ; 42(14): 1213-42, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14606930

RESUMO

Modifications to bodily functions and physiology are known to occur with age. These changes can have a considerable impact on the pharmacokinetic processes of absorption, distribution, metabolism and excretion and the pharmacodynamic properties of administered drugs. For many drugs with a high therapeutic index, this will be clinically unimportant, but for anticancer drugs, which usually have a low therapeutic index, these pharmacological changes can lead to dramatic consequences, such as excessive drug concentrations and unacceptable toxicity, or subtherapeutic drug concentrations and ineffective treatment. Despite the increased susceptibility of the elderly to these changes, doses are rarely adapted on the basis of pharmacokinetics and pharmacodynamics, with the exception of changes secondary to altered renal function. Until recently, only a few large prospective randomised trials have provided evidence-based data for dose adaptations in elderly patients. However, with increasing knowledge of the pharmacokinetics of anticancer drugs, advances in the knowledge of pharmacokinetic behaviour with aging, and documented efficacy and toxicity data in the elderly population, it is possible to highlight aspects of prescribing anticancer drugs in the elderly. In general, and for most drugs, age itself is not a contraindication to full-dose chemotherapy. The main limiting factors are comorbidity and poor functional status, which may be present in a significant number of the elderly population. Elderly patients with cancer are part of the daily practice of oncologists, but currently clinicians can often only estimate whether dose modification is advantageous for the elderly. This review attempts to elucidate the factors that can influence the pharmacokinetics of anticancer drugs frequently used in the elderly, and the clinical or biochemical parameters that form the basis for dose adjustments with age.


Assuntos
Envelhecimento , Antineoplásicos/farmacologia , Antineoplásicos/farmacocinética , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/efeitos adversos , Interações Medicamentosas , Idoso Fragilizado , Humanos , Neoplasias/tratamento farmacológico , Cooperação do Paciente , Ensaios Clínicos Controlados Aleatórios como Assunto
20.
Clin Cancer Res ; 9(4): 1313-22, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12684399

RESUMO

PURPOSE: ZD9331 is a novel, direct-acting antifolate cytotoxic that does not require polyglutamation for activity, and is a specific thymidylate synthase inhibitor. This Phase I trial aimed to determine the maximum tolerated dose of ZD9331, given as a 30-min i.v. infusion on days 1 and 8 of a 21-day cycle. Pharmacokinetic parameters and tumor response were also assessed. EXPERIMENTAL DESIGN: A total of 71 patients, with a range of solid malignancies and refractory to standard therapies (44% had received > or =3 prior chemotherapy regimens), were treated. The most common malignancies were colorectal cancer (35% of patients) and ovarian cancer (31%). ZD9331 was escalated from 4.8 mg/m(2)/day. RESULTS: Dose-limiting toxicity occurred at 162.5 mg/m(2) ZD9331, with grade 4 thrombocytopenia, grade 4 neutropenia lasting > or =7 days, and grade 3 nonhematologic toxicity. Plasma clearance of ZD9331 was slow and dose-dependent; however, ZD9331 pharmacokinetics were nonlinear. Pharmacodynamics of ZD9331 were determined by measurement of plasma deoxyuridine, which increased at all of the dose levels; dose-related increases in plasma deoxyuridine were significant (P = 0.003) on day 5. Stable disease was observed in 37% of patients; 23% of ovarian cancer patients had a > or =50% reduction in CA125 levels. CONCLUSIONS: The maximum tolerated dose of this schedule was 130 mg/m(2). The toxicity profile at this dose was acceptable, with 7 of 28 patients treated developing grade 3/4 neutropenia and thrombocytopenia, 2 grade 4 diarrhea, and 2 grade 3/4 rash. This schedule was convenient and demonstrated activity in extensively pretreated patients; therefore, this is the recommended dose for study in Phase II trials.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias/tratamento farmacológico , Quinazolinas/uso terapêutico , Timidilato Sintase/antagonistas & inibidores , Adulto , Idoso , Antineoplásicos/farmacocinética , Área Sob a Curva , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Modelos Químicos , Quinazolinas/farmacocinética , Fatores de Tempo , Água/química
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