964 resultados para Combination therapy


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BACKGROUND: Prostate cancer is the most common type of cancer in men, however, therapeutic options are limited. 50-90% of hormone-refractory prostate cancer cells show an overexpression of epidermal growth factor receptor (EGFR), which may contribute to uncontrolled proliferation and resistance to chemotherapy. In vitro, gefitinib, an orally administered tyrosine kinase inhibitor, has shown a significant increase in antitumor activity when combined with chemotherapy. PATIENTS AND METHODS: In this phase II study, the safety and efficacy of gefitinib in combination with docetaxel, a chemotherapeutic agent commonly used for prostate cancer, was investigated in patients with hormone-refractory prostate cancer (HRPC). 37 patients with HRPC were treated continuously with gefitinib 250 mg once daily and docetaxel 35 mg/m2 i.v. for up to 6 cycles. PSA response, defined as a =50% decrease in serum PSA compared with trial entry, was the primary efficacy parameter. PSA levels were measured at prescribed intervals. RESULTS: The response rate and duration of response were consistent with those seen with docetaxel monotherapy. The combination of docetaxel and gefitinib was reasonably well tolerated in this study. CONCLUSION: Future studies should investigate whether patients with specific tumor characteristics, e.g. EGFR protein overexpression, respond better to gefitinib than patients without, leading to a more customized therapy option.

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Chemotherapy continues to play an essential role in the treatment of most stages of non-small-cell lung cancer (NSCLC). In fact, within the past 5 years, this role has greatly expanded into adjuvant therapy for early-stage resected disease. Likewise, agents targeting the epidermal growth factor receptor (EGFR), particularly the tyrosine kinase inhibitors gefitinib and erlotinib, have proven to be clinically active in patients with advanced-stage NSCLC. Because of these findings, it is logical to expect that combinations of these 2 classes of antineoplastic agents would prove more efficacious than either one alone. Yet 4 large randomized phase III trials of chemotherapy with or without an EGFR tyrosine kinase inhibitor in unselected patients with advanced-stage NSCLC, altogether totaling > 4000 patients, did not demonstrate improvement in clinical outcomes with the combination. Whether these negative results will be reproduced in ongoing combination studies of chemotherapy plus monoclonal antibodies directed against EGFR remain to be determined. Herein, we review recent preclinical and clinical data addressing this topic and explore the biologic rationale for developing new combination strategies based on patient selection by molecular and clinical factors, or by pharmacodynamic parameters.

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OBJECTIVE: To compare the effect of bimatoprost and the fixed combination of latanoprost and timolol (LTFC) on 24-hour mean intraocular pressure (IOP) after patients are switched from a nonfixed combination of latanoprost and timolol. DESIGN: Randomized, double-masked, multicenter clinical trial. PARTICIPANTS: Two hundred patients with glaucoma or ocular hypertension. METHODS: Included were patients who were controlled (IOP < 21 mmHg) on the nonfixed combination of latanoprost and timolol for at least 3 months before the baseline visit or patients on monotherapy with either latanoprost or timolol who were eligible for dual therapy not being fully controlled on monotherapy. The latter group of patients underwent a 6-week wash-in phase with the nonfixed combination of latanoprost and timolol before baseline IOP determination and study inclusion. Supine and sitting position IOPs were recorded at 8 pm, midnight, 5 am, 8 am, noon, and 4 pm at baseline, week 6, and week 12 visits. MAIN OUTCOME MEASURE: An analysis of covariance model was used for a noninferiority test of the primary efficacy variable, with mean area under the 24-hour IOP curve after 12 weeks of treatment as response variable and treatment, center, and baseline IOP as factors. A secondary analysis was performed on the within-treatment change from baseline. RESULTS: Mean baseline IOPs were 16.3+/-3.3 mmHg and 15.5+/-2.9.mmHg in the bimatoprost and LTFC groups, respectively. At week 12, mean IOPs were 16.1+/-2.5 mmHg for the bimatoprost group and 16.3+/-3.7 mmHg for the LTFC group, and no significant difference between the 2 treatment groups could be found. As compared with baseline, mean IOP increased by 0.3+/-3.6 mmHg during the day and decreased by 0.8+/-3.8 mmHg during the night in the bimatoprost group, whereas there were increases of 1.43+/-2.6 mmHg and 0.14+/-3.2 mmHg in the LTFC group, respectively. CONCLUSIONS: Bimatoprost is not inferior to the LTFC in maintaining IOP at a controlled level during a 24-hour period in patients switched from the nonfixed combination of latanoprost and timolol.

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OBJECTIVE: To assess the characteristics of combination antiretroviral therapy (cART) administered concomitantly with chemotherapy and to establish prognostic determinants of patients with AIDS-related non-Hodgkin's lymphoma. METHODS: The study included 91 patients with AIDS-related non-Hodgkin's lymphoma from the Swiss HIV Cohort Study enrolled between January 1997 and October 2003, excluding lymphomas of the brain. We extracted AIDS-related non-Hodgkin's lymphoma- and HIV-specific variables at the time of lymphoma diagnosis as well as treatment changes over time from charts and from the Swiss HIV Cohort Study database. Cox regression analyses were performed to study predictors of overall and progression-free survival. RESULTS: During a median follow up of 1.6 years, 57 patients died or progressed. Thirty-five patients stopped chemotherapy prematurely (before the sixth cycle) usually due to disease progression; these patients had a shorter median survival than those who completed six or more cycles (14 versus 28 months). Interruptions of cART decreased from 35% before chemotherapy to 5% during chemotherapy. Factors associated with overall survival were CD4+ T-cell count (<100 cells/microl) (hazard ratio [HR] 2.95 [95% confidence interval (CI) 1.53-5.67], hepatitis C seropositivity (HR 2.39 [95% CI 1.01-5.67]), the international prognostic index score (HR 1.98-3.62 across categories) and Burkitt histological subtypes (HR 2.56 [95% CI 1.13-5.78]). CONCLUSIONS: Interruptions of cART were usually not induced by chemotherapy. The effect of cART interruptions on AIDS-related non-Hodgkin's lymphoma prognosis remains unclear, however, hepatitis C seropositivity emerged-as a predictor of death beyond the well-known international prognostic index score and CD4+ T-cell count.

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BACKGROUND: CD4+ T-cell recovery in patients with continuous suppression of plasma HIV-1 viral load (VL) is highly variable. This study aimed to identify predictive factors for long-term CD4+ T-cell increase in treatment-naive patients starting combination antiretroviral therapy (cART). METHODS: Treatment-naive patients in the Swiss HIV Cohort Study reaching two VL measurements <50 copies/ml >3 months apart during the 1st year of cART were included (n=1816 patients). We studied CD4+ T-cell dynamics until the end of suppression or up to 5 years, subdivided into three periods: 1st year, years 2-3 and years 4-5 of suppression. Multiple median regression adjusted for repeated CD4+ T-cell measurements was used to study the dependence of CD4+ T-cell slopes on clinical covariates and drug classes. RESULTS: Median CD4+ T-cell increases following VL suppression were 87, 52 and 19 cells/microl per year in the three periods. In the multiple regression model, median CD4+ T-cell increases over all three periods were significantly higher for female gender, lower age, higher VL at cART start, CD4+ T-cell <650 cells/microl at start of the period and low CD4+ T-cell increase in the previous period. Patients on tenofovir showed significantly lower CD4+ T-cell increases compared with stavudine. CONCLUSIONS: In our observational study, long-term CD4+ T-cell increase in drug-naive patients with suppressed VL was higher in regimens without tenofovir. The clinical relevance of these findings must be confirmed in, ideally, clinical trials or large, collaborative cohort projects but could influence treatment of older patients and those starting cART at low CD4+ T-cell levels.

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OBJECTIVES: To assess the prevalence of abnormal testosterone and gonadotropin values in HIV-infected men before and after 2 years of combination antiretroviral therapy (cART). DESIGN: Multicentre cohort of HIV-infected adults. METHODS: We identified 139 Caucasian antiretroviral-naive male patients who started zidovudine/ lamivudine-based cART that was virologically successful over a 2 year period. Ninety-seven were randomly chosen and plasma hormone determinations of free testosterone (fT) and luteinizing hormone (LH) at baseline and after 2 years of cART were evaluated. RESULTS: At baseline 68 patients (70%) had subnormal fT levels. In these, LH levels were low in 44%, normal in 47% and high in 9%. There was a trend for an association between lower CD4+ T-cell counts and hypogonadism. Most participants had normal FSH levels. No significant changes of fT, LH and FSH levels were observed after 2 years of cART. CONCLUSIONS: Low fT levels, mainly with normal or low LH levels and thus indicating secondary hypogonadism, are found in the majority of HIV-infected men and do not resolve during 2 years of successful cART.

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OBJECTIVES: To assess the correlations between the hormone leptin and lipoatrophy in HIV-positive, treatment-naive patients on combination antiretroviral therapy (cART). DESIGN: Case-control study nested in a multicentre cohort of HIV-infected adults. Cases were patients that developed lipoatrophy and controls those who did not. PATIENTS AND METHODS: Clinical parameters and plasma leptin determinations were studied in 97 HIV-1-infected, treatment-naive Caucasian men (10 cases and 87 controls) on an unchanged and virologically successful drug regimen with a zidovudine/lamivudine backbone at baseline and after 2 years of cART. The association of plasma leptin levels and the development of lipoatrophy was investigated. RESULTS: Two years of cART was not associated with a change in plasma leptin levels. Plasma leptin levels remained sensible to changes in body mass index. There was no difference in leptin levels between patients who developed lipoatrophy and controls, neither before nor after cART. The only predictor of development of lipoatrophy was a higher age (P = 0.02). CONCLUSIONS: Leptin as measured in plasma is unlikely to play a major role in the genesis of lipoatrophy.

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Rifampin at a maximally effective dose was less active than ceftriaxone (both drugs at 10 mg/kg of body weight.h) in a rabbit model of pneumococcal meningitis (delta log10 CFU/ml.h, -0.40 +/- 0.13 versus -0.77 +/- 0.18; P < 0.01). The bactericidal activity of rifampin decreased at concentrations in cerebrospinal fluid greater than those that are clinically achievable, and use of rifampin in combination with ofloxacin had no synergistic or additive effect.

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The second part of the present review article presents and discusses the current literature regarding cytodiagnostic aspects, pathogenesis, therapy, incidence of recurrence, and malignant transformation rate of oral erythroplakia (OE) and oral erythroleukoplakia (OEL). Oral cytopathology, eventually in combination with DNA cytometry, can add valuable information to conventional histopathology, but is not able yet to replace the aforementioned. Numerous molecular genetic variants have been studied in precancerous lesions to gain knowledge about the prognosis of these lesions. Still, there are no evidence-based parameters available to safely detect precursor lesions that will undergo malignant transformation in the future. Excision of OE and OEL should be performed with a margin of safety using the CO2 laser or a scalpel. Data about incidence of recurrence and malignant tranformation rates of OE are mostly based upon case reports or case series. The OEL has a significantly higher risk of malignant transformation than oral leukoplakias.

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Overexpression of the transcription factor E2F-1 induces apoptosis in tumor cells. This apoptotic effect is partly mediated through the induction of the double-stranded RNA-activated protein kinase (PKR). Here, we investigate if agents that upregulate PKR could enhance the apoptotic effect of E2F-1 overexpression in liver tumors. In human hepatocellular carcinoma (HCC) cells (Hep3B, HepG2, Huh7), adenovirus-mediated overexpression of E2F-1 (AdCMV-E2F) transcriptionally increased PKR mRNA. The subsequent increase of total and phosphorylated PKR protein was followed by induction of apoptosis. When AdCMV-E2F was combined with the PKR modifier interferon alpha (IFNalpha), PKR was additionally upregulated and both PKR activation and apoptosis were increased. Subcutaneous xenograft tumors were selectively targeted using an adenoviral vector expressing E2F-1 under the control of the human telomerase reverse transcriptase (hTERT) promoter (AdhTERT-E2F). Weekly systemic administration of AdhTERT-E2F inhibited tumor growth. The tumor suppressive effect of AdhTERT-E2F therapy was further enhanced in combination with IFNalpha.Our results demonstrate that PKR activating agents enhance the anti-tumor effect of E2F-1 overexpression in HCC in-vitro and in-vivo. Hence, modulation of PKR is a potential strategy to increase the efficacy of PKR-dependent anti-tumor therapies.

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OBJECTIVES: To describe temporal trends in baseline clinical characteristics, initial treatment regimens and monitoring of patients starting antiretroviral therapy (ART) in resource-limited settings. METHODS: We analysed data from 17 ART programmes in 12 countries in sub-Saharan Africa, South America and Asia. Patients aged 16 years or older with documented date of start of highly active ART (HAART) were included. Data were analysed by calculating medians, interquartile ranges (IQR) and percentages by regions and time periods. Not all centres provided data for 2006 and 2005 and 2006 were therefore combined. RESULTS: A total of 36,715 patients who started ART 1996-2006 were included in the analysis. Patient numbers increased substantially in sub-Saharan Africa and Asia, and the number of initial regimens declined, to four and five, respectively, in 2005-2006. In South America 20 regimes were used in 2005-2006. A combination of 3TC/D4T/NVP was used for 56% of African patients and 42% of Asian patients; AZT/3TC/EFV was used in 33% of patients in South America. The median baseline CD4 count increased in recent years, to 122 cells/microl (IQR 53-194) in 2005-2006 in Africa, 134 cells/microl (IQR 72-191) in Asia, and 197 cells/microl (IQR 61-277) in South America, but 77%, 78% and 51%, respectively, started with <200 cells/microl in 2005-2006. In all regions baseline CD4 cell counts were higher in women than men: differences were 22cells/microl in Africa, 65 cells/microl in Asia and 10 cells/microl in South America. In 2005-2006 a viral load at 6 months was available in 21% of patients Africa, 8% of Asian patients and 73% of patients in South America. Corresponding figures for 6-month CD4 cell counts were 74%, 77% and 81%. CONCLUSIONS: The public health approach to providing ART proposed by the World Health Organization has been implemented in sub-Saharan Africa and Asia. Although CD4 cell counts at the start of ART have increased in recent years, most patients continue to start with counts well below the recommended threshold. Particular attention should be paid to more timely initiation of ART in HIV-infected men.

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OBJECTIVE: To determine whether differences in short-term virologic failure among commonly used antiretroviral therapy (ART) regimens translate to differences in clinical events in antiretroviral-naïve patients initiating ART. DESIGN: Observational cohort study of patients initiating ART between January 2000 and December 2005. SETTING: The Antiretroviral Therapy Cohort Collaboration (ART-CC) is a collaboration of 15 HIV cohort studies from Canada, Europe, and the United States. STUDY PARTICIPANTS: A total of 13 546 antiretroviral-naïve HIV-positive patients initiating ART with efavirenz, nevirapine, lopinavir/ritonavir, nelfinavir, or abacavir as third drugs in combination with a zidovudine and lamivudine nucleoside reverse transcriptase inhibitor backbone. MAIN OUTCOME MEASURES: Short-term (24-week) virologic failure (>500 copies/ml) and clinical events within 2 years of ART initiation (incident AIDS-defining event, death, and a composite measure of these two outcomes). RESULTS: Compared with efavirenz as initial third drug, short-term virologic failure was more common with all other third drugs evaluated; nevirapine (adjusted odds ratio = 1.87, 95% confidence interval (CI) = 1.58-2.22), lopinavir/ritonavir (1.32, 95% CI = 1.12-1.57), nelfinavir (3.20, 95% CI = 2.74-3.74), and abacavir (2.13, 95% CI = 1.82-2.50). However, the rate of clinical events within 2 years of ART initiation appeared higher only with nevirapine (adjusted hazard ratio for composite outcome measure 1.27, 95% CI = 1.04-1.56) and abacavir (1.22, 95% CI = 1.00-1.48). CONCLUSION: Among antiretroviral-naïve patients initiating therapy, between-ART regimen, differences in short-term virologic failure do not necessarily translate to differences in clinical outcomes. Our results should be interpreted with caution because of the possibility of residual confounding by indication.

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OBJECTIVES: We compared androgen and gonadotropin values in HIV-infected men who did and did not develop lipoatrophy on combination antiretroviral therapy (cART). METHODS: From a population of 136 treatment-naïve male Caucasians under successful zidovudine/lamivudine-based cART, the 10 patients developing lipoatrophy (cases) were compared with 87 randomly chosen controls. Plasma levels of free testosterone (fT), dehydroepiandrosterone (DHEA), follicle-stimulating hormone and luteinizing hormone (LH) were measured at baseline and after 2 years of cART. RESULTS: At baseline, 60% of the cases and 71% of the controls showed abnormally low fT values. LH levels were normal or low in 67 and 94% of the patients, respectively, indicating a disturbance of the hypothalamic-pituitary-gonadal axis. fT levels did not significantly change after 2 years of cART. Cases showed a significant increase in LH levels, while controls showed a significant increase in DHEA levels. In a multivariate logistic regression model, lipoatrophy was associated with higher baseline DHEA levels (P=0.04), an increase in LH levels during cART (P=0.001), a lower body mass index and greater age. CONCLUSIONS: Hypogonadism is present in the majority of HIV-infected patients. The development of cART-related lipoatrophy is associated with an increase in LH and a lack of increase in DHEA levels.

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OBJECTIVE: To describe the use of stem cells (SCs) for regeneration of retinal degenerations. Regenerative medicine intends to provide therapies for severe injuries or chronic diseases where endogenous repair does not sufficiently restore the tissue. Pluripotent SCs, with their capacity to give rise to specialized cells, are the most promising candidates for clinical application. Despite encouraging results, a combination with up-to-date tissue engineering might be critical for ultimate success. DESIGN: The focus is on the use of SCs for regeneration of retinal degenerations. Cell populations include embryonic, neural, and bone marrow-derived SCs, and engineered grafts will also be described. RESULTS: Experimental approaches have successfully replaced damaged photoreceptors and retinal pigment epithelium using endogenous and exogenous SCs. CONCLUSIONS: Stem cells have the potential to significantly impact retinal regeneration. A combination with bioengineering may bear even greater promise. However, ethical and scientific issues have yet to be solved.

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BACKGROUND: Exudative age-related macular degeneration (AMD) is a sight-threatening event in many elderly people. Some patients have a much better outcome in visual acuity (VA) than others after treatment with photodynamic therapy (PDT) with verteporfin. The combination of fluorescein angiography (FA) and indocyanine green (ICG) angiography using the Heidelberg Retina Angiograph II (HRA 2) should make a delineation of distinct pattern(s) possible in order to better select and assess therapy. METHODS: This is a retrospective, case-control, single-centre study. We identified a total of 168 eyes of 168 patients from July 2003 to June 2006, including 30 eyes of 30 patients with better visual outcome, defined in this study as VA < or = 0.48 logMAR (> or =20/60 Snellen chart) at the end of the study. Best-corrected VA, maximal central retinal thickness as measured by optical coherence tomography, and results of the FA/ICG angiography using the HRA 2 were analyzed. In this article, we discuss patients with polypoidal choroidal vasculopathy (PCV) and their characteristics. RESULTS: The average follow-up time was 15.3 months (range 4-28 months). Seventeen (57%) of the 30 patients with better visual outcome had PCV. All patients in the group with better visual outcome needed fewer PDT treatments compared with our control group of patients with an exudative AMD. INTERPRETATION: Simultaneous FA/ICG angiography using the HRA 2 allowed delineation of a subgroup of patients with PCV who showed a better visual outcome compared with those with other types of exudative AMD, after treatment with PDT.