Large Randomized Trials (large + randomized_trials)

Distribution by Scientific Domains


Selected Abstracts


Lopinavir/ritonavir monotherapy as maintenance treatment in HIV-infected individuals with virological suppression: results from a pilot study in Brazil

HIV MEDICINE, Issue 5 2008
E Sprinz
Objective The aim of the study was to evaluate the possibility of using lopinavir/ritonavir (LPV/RTV) alone as maintenance therapy in HIV-infected individuals with virological suppression. Design This was a single-armed single-centre pilot trial. Methods Asymptomatic HIV-infected patients on highly active antiretroviral therapy (HAART) including LPV/RTV, and with plasma HIV RNA <40 copies/mL for at least 6 months, were enrolled in the study, during which they continued with LPV/RTV alone. The intention was to recruit 25 patients to be followed for 2 years. Viral failure was defined as two consecutive HIV RNA measurements >40 copies/mL. Nadir and baseline CD4 cell counts, highest ever HIV RNA load, time with undetectable viraemia before monotherapy, number of previous antiretroviral (ARV) regimens, and gene polymorphism at CYP3A4 and CYP3A5 were evaluated. Results All patients (27) completed the study. Their median age was 43 years, and 66% were men. Ten patients (37%) failed to maintain virological suppression (the median time to HIV rebound was 10.5 months, with a range of 4,23 months). One patient developed full resistance to LPV and another developed neurocognitive impairment while on LPV/RTV which improved after HAART reintroduction. There were no differences between failures and nonfailures according to the analysed parameters. Patients with viral failure were successfully resuppressed. Conclusions LPV/RTV maintenance therapy was associated with 37% failure, a higher than expected failure rate. In order to ensure that unnecessary risks are not being taken in patients on LPV/RTV, this finding should be further evaluated in large randomized trials for longer periods of follow-up. [source]


Clinical outcomes with unfractionated heparin or low-molecular-weight heparin as bridging therapy in patients on long-term oral anticoagulants: the REGIMEN registry,

JOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 6 2006
A. C. SPYROPOULOS
Summary.,Background: Patients who receive long-term oral anticoagulant (OAC) therapy often require interruption of OAC for an elective surgical or an invasive procedure. Heparin bridging therapy has been used in these situations, although the optimal method has not been established. No large prospective studies have compared unfractionated heparin (UFH) with low-molecular-weight heparin (LMWH) for the perioperative management of patients at risk of thromboembolism requiring temporary interruption of long-term OAC therapy. Patients/methods: This multicenter, observational, prospective registry conducted in North America enrolled 901 eligible patients on long-term OAC who required heparin bridging therapy for an elective surgical or invasive procedure. Practice patterns and clinical outcomes were compared between patients who received either UFH alone (n = 180) or LMWH alone (n = 721). Results: Overall, the majority of patients (74.5%) requiring heparin bridging therapy had arterial indications for OAC. LMWH, in mostly twice-daily treatment doses, represented approximately 80% of the study population. LMWH-bridged patients had significantly fewer arterial indications for OAC, a lower mean Charlson comorbidity score, and were less likely to undergo major or cardiothoracic surgery, receive intraprocedural anticoagulants or thrombolytics, or receive general anesthesia than UFH-bridged patients (all P < 0.05). The LMWH group had significantly more bridging therapy completed in an outpatient setting or with a < 24-h hospital stay vs. the UFH group (63.6% vs. 6.1%, P < 0.001). In the LMWH and UFH groups, similar rates of overall adverse events (16.2% vs. 17.1%, respectively, P = 0.81), major composite adverse events (arterial/venous thromboembolism, major bleed, and death; 4.2% vs. 7.9%, respectively, P = 0.07) and major bleeds (3.3% vs. 5.5%, respectively, P = 0.25) were observed. The thromboembolic event rates were 2.4% for UFH and 0.9% for LMWH. Logistic regression analysis revealed that for postoperative heparin use a Charlson comorbidity score > 1 was an independent predictor of a major bleed and that vascular, general, and major surgery were associated with non-significant trends towards an increased risk of major bleed. Conclusions: Treatment-dose LMWH, mostly in the outpatient setting, is used substantially more often than UFH as bridging therapy in patients with predominately arterial indications for OAC. Overall adverse events, including thromboembolism and bleeding, are similar for patients treated with LMWH or UFH. Postoperative heparin bridging should be used with caution in patients with multiple comorbidities and those undergoing vascular, general, and major surgery. These findings need to be confirmed using large randomized trials for specific patient groups undergoing specific procedures. [source]


Beta-carotene in multivitamins and the possible risk of lung cancer among smokers versus former smokers

CANCER, Issue 1 2008
A meta-analysis, evaluation of national brands
Abstract BACKGROUND Some studies have suggested that beta-carotene supplementation may increase the risk of lung cancer, particularly among smokers or former smokers. Beta-carotene, a provitamin A, is available in multivitamins. In the current study, the authors investigated the risk of lung cancer associated with beta-carotene in smokers or former smokers and surveyed the beta-carotene content in national brand multivitamins. METHODS The authors systemically reviewed the published literature using a search of the MEDLINE database and performed a meta-analysis of large randomized trials that reported on the effect of beta-carotene supplementation on the incidence of lung cancer among smokers or former smokers. A sample of multivitamins was evaluated for their beta-carotene content and the suggested daily dosage. RESULTS Four studies contributing 109,394 subjects were available for analysis. The average daily beta-carotene dosage in these trials ranged from 20 to 30 mg daily. Among current smokers, beta-carotene supplementation was found to be significantly associated with an increased risk of lung cancer (odds ratio [OR], 1.24; 95% confidence interval [95% CI], 1.10,1.39). Among former smokers, there was no significant increase noted (OR, 1.10; 95% CI, 0.84,1.45). In a sample of 47 common multivitamins, beta-carotene was present in 70% of the identified formulas. The median dosage of beta-carotene was 0.3 mg (range, 0,17.2 mg) daily. The beta-carotene content was found to be significantly higher among multivitamins sold to improve visual health than among other multivitamins, with a median daily dosage of 3 mg (range, 0,24 mg). CONCLUSIONS High-dose beta-carotene supplementation appears to increase the risk of lung cancer among current smokers. Although beta-carotene was prevalent in multivitamins, high-dose beta-carotene was observed among multivitamin formulas sold to promote visual health. Cancer 2008. © 2008 American Cancer Society. [source]


Outcomes with drug-eluting stents versus bare metal stents in acute ST-elevation myocardial infarction: Results from the Strategic Transcatheter Evaluation of New Therapies (STENT) Group,

CATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 7 2008
Bruce R. Brodie MD
Abstract Objectives: This study compares outcomes with drug-eluting stents (DES) versus bare metal stents (BMS) in patients with ST-elevation myocardial infarction (STEMI). Background: DESs have been effective in elective percutaneous coronary intervention (PCI), but their safety and efficacy in patients with STEMI have not been well studied. Methods: The STENT Registry is a multicenter United States registry evaluating outcomes of DES. Our study population includes patients with STEMI treated with either a DES or BMS who completed 9-month or 2-year follow-up. Outcomes were adjusted using propensity score analysis. Results: DES patients were younger, had less prior infarction and prior bypass surgery, but had smaller vessels and longer lesions. After adjusting for differences in baseline variables, there were no significant differences between DES and BMS in death, reinfarction, or major adverse cardiac events (MACE). DES had lower rates of stent thrombosis at 9 months (1.0% vs. 2.7%, HR 0.40 [0.17,0.95]) and lower rates of target vessel revascularization (TVR) at 9 months (4.0% vs. 7.5%, HR 0.55 [0.34,0.88]) and 2 years (8.0% vs. 11.3%, HR 0.57 [0.35,0.92]). There was a nonsignificant increase in stent thrombosis with DES versus BMS from 1 to 2 years (1.1% vs. 0.3%, P = 0.28). Conclusions: Our data suggest that DES used with primary PCI for STEMI are more effective than BMS in reducing TVR and are safe for up to 2 years. Whether DES are safe beyond 2 years and whether the reduction in TVR is enough to justify their use in STEMI will have to wait for the results of large randomized trials. 2008 Wiley-Liss, Inc. [source]