Day: 01/19/2012

Neuraminidase inhibitors for preventing and treating influenza in healthy adults and children.

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Planning for outbreaks of influenza is a high priority public health issue for national governments. Neuraminidase inhibitors (NIs) are thought to help reduce the symptoms of influenza with several possible mechanisms proposed. NIs have been stockpiled with a view to their widespread use in the event of a pandemic. However, the evidence base for this class of agents remains a source of debate. In a previous review we have documented substantial risks of publication bias of trials of NIs for influenza (60% of patient data from phase III treatment trials of oseltamivir have never been published) and reporting bias in the published trials. Our confidence in the conclusions of previous versions of this review has been subsequently undermined. Since we have become aware of a large number of unpublished trials of NIs in the management of influenza, this review updates and merges existing reviews in this area.

Objectives

To review clinical study reports of placebo-controlled randomised trials, regulatory comments and reviews (‘regulatory information’) of the effects of the NIs oseltamivir and zanamivir for influenza in all age groups and appraise trial programmes, rather than single studies.

Clinical study reports are very detailed, unpublished clinical trial data containing in-depth descriptions of protocol rationale, methods analysis plans, trial results and organisational documents (such as contracts). A series of clinical studies designed and conducted by one sponsor represents a trial programme of a drug indication (for example treatment of influenza).

Search methods

We searched trial registries, cross-referencing published and unpublished sources and corresponded with manufacturers and regulators. We searched the archives of the US Food and Drug Administration (FDA) and European and Japanese regulators. The evidence in this review reflects searches to obtain relevant information up to 12 April 2011.

Selection criteria

We included regulatory information based on assessments of randomised controlled trials (RCTs) conducted in people of any age who had either confirmed or suspected influenza, or who had been exposed to influenza in the local community or place of residence. We included information which had been made available by our deadline.

Data collection and analysis

We indexed regulatory information in two purpose-built instruments and reconstructed trials using CONSORT statement-based templates. To progress to Stage 2 (full analysis) we sought manufacturer explanations of discrepancies in the data. GlaxoSmithKline (GSK) offered us individual patient data and responded to our queries, but Roche did not provide us with complete clinical study reports. In Stage 2 we intended to analyse trials with validated data (i.e. assuming our validation questions aimed at clarifying omissions and discrepancies were resolved). No studies progressed to Stage 2. We carried out analyses of the effects of oseltamivir on time to first alleviation of symptoms and hospitalisations using the intention-to-treat (ITT) population and tested five hypotheses generated post-protocol publication.

Main results

We included and analysed data from 25 studies (15 oseltamivir and 10 zanamivir studies). We could not use data from a further 42 studies due to insufficient information or unresolved discrepancies in their data. The included trials were predominantly conducted in adults during influenza seasons in both hemispheres. A small number of studies were conducted in older people residing in care homes and in people with underlying respiratory diseases. The studies had adequate randomisation and blinding procedures, but imbalances in the analysis populations available (ITT influenza-infected) left many of the studies at risk of attrition bias. All the studies were sponsored by manufacturers of NIs. Time to first alleviation of symptoms in people with influenza-like illness symptoms (i.e. ITT population) was a median of 160 hours (range 125 to 192 hours) in the placebo groups and oseltamivir shortened this by around 21 hours (95% confidence interval (CI) -29.5 to -12.9 hours, P < 0.001; five studies) but there was no evidence of effect on hospitalisations based on seven studies with a median placebo group event rate of 0.84% (range 0% to 11%): odds ratio (OR) 0.95; 95% CI 0.57 to 1.61, P = 0.86). These results are based on the comprehensive ITT population data and are unlikely to be biased. A post-protocol analysis showed that participants randomised to oseltamivir in treatment trials had a reduced odds being diagnosed with influenza (OR 0.83; 95% CI 0.73 to 0.94, P = 0.003; eight studies), probably due to an altered antibody response. Zanamivir trials showed no evidence of this. Due to limitations in the design, conduct and reporting of the trial programme, the data available to us lacked sufficient detail to credibly assess a possible effect of oseltamivir on complications and viral transmission. We postponed analysis of zanamivir evidence because of the offer of individual patient data (IPD) from its manufacturer. The authors have been unable to obtain the full set of clinical study reports or obtain verification of data from the manufacturer of oseltamivir (Roche) despite five requests between June 2010 and February 2011. No substantial comments were made by Roche on the protocol of our Cochrane Review which has been publicly available since December 2010.

Authors’ conclusions

We found a high risk of publication and reporting biases in the trial programme of oseltamivir. Sub-population analyses of the influenza infected population in the oseltamivir trial programme are not possible because the two arms are non-comparable due to oseltamivir’s apparent interference with antibody production. The evidence supports a direct oseltamivir mechanism of action on symptoms but we are unable to draw conclusions about its effect on complications or transmission. We expect full clinical study reports containing study protocol, reporting analysis plan, statistical analysis plan and individual patient data to clarify outstanding issues. These full clinical study reports are at present unavailable to us.

Source:Cochrane Library.

Neuromodulators for pain management in rheumatoid arthritis.

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Pain management is a high priority for patients with rheumatoid arthritis (RA). Despite deficiencies in research data, neuromodulators have gained widespread clinical acceptance as adjuvants in the management of patients with chronic musculoskeletal pain.

Objectives

The aim of this review was to determine the efficacy and safety of neuromodulators in pain management in patients with RA. Neuromodulators included in this review were anticonvulsants (gabapentin, pregabalin, phenytoin, sodium valproate, lamotrigine, carbamazepine, levetiracetam, oxcarbazepine, tiagabine and topiramate), ketamine, bupropion, methylphenidate, nefopam, capsaicin and the cannabinoids.

Search methods

We performed a computer-assisted search of the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2010, 4th quarter), MEDLINE (1950 to week 1 November 2010), EMBASE (Week 44, 2010) and PsycINFO (1806 to week 2 November 2010). We also searched the 2008 and 2009 American College of Rheumatology (ACR) and European League against Rheumatism (EULAR) conference abstracts and performed a handsearch of reference lists of articles.

Selection criteria

We included randomised controlled trials which compared any neuromodulator to another therapy (active or placebo, including non-pharmacological therapies) in adult patients with RA that had at least one clinically relevant outcome measure.

Data collection and analysis

Two blinded review authors independently extracted data and assessed the risk of bias in the trials. Meta-analyses were used to examine the efficacy of a neuromodulator on pain, depression and function as well as their safety.

Main results

Four trials with high risk of bias were included in this review. Two trials evaluated oral nefopam (52 participants) and one trial each evaluated topical capsaicin (31 participants) and oromucosal cannabis (58 participants).

The pooled analyses identified a significant reduction in pain levels favouring nefopam over placebo (weighted mean difference (WMD) -21.16, 95% CI -35.61 to -6.71; number needed to treat (NNT) 2, 95% CI 1.4 to 9.5) after two weeks. There were insufficient data to assess withdrawals due to adverse events. Nefopam was associated with significantly more adverse events (RR 4.11, 95% CI 1.58 to 10.69; NNTH 9, 95% CI 2 to 367), which were predominantly nausea and sweating.

In a mixed population trial, qualitative analysis of patients with RA showed a significantly greater reduction in pain favouring topical capsaicin over placebo at one and two weeks (MD -23.80, 95% CI -44.81 to -2.79; NNT 3, 95% CI 2 to 47; MD -34.40, 95% CI -54.66 to -14.14; NNT 2, 95% CI 1.4 to 6 respectively). No separate safety data were available for patients with RA, however 44% of patients developed burning at the site of application and 2% withdrew because of this.

One small, low quality trial assessed oromucosal cannabis against placebo and found a small, significant difference favouring cannabis in the verbal rating score ‘pain at present’ (MD -0.72, 95% CI -1.31 to -0.13) after five weeks. Patients receiving cannabis were significantly more likely to suffer an adverse event (risk ratio (RR) 1.82, 95% CI 1.10 to 3.00; NNTH 3, 95% CI 3 to 13). These were most commonly dizziness (26%), dry mouth (13%) and light headedness (10%).

Authors’ conclusions

There is currently weak evidence that oral nefopam, topical capsaicin and oromucosal cannabis are all superior to placebo in reducing pain in patients with RA. However, each agent is associated with a significant side effect profile. The confidence in our estimates is not strong given the difficulties with blinding, the small numbers of participants evaluated and the lack of adverse event data. In some patients, however, even a small degree of pain relief may be considered worthwhile. Until further research is available, given the relatively mild nature of the adverse events, capsaicin could be considered as an add-on therapy for patients with persistent local pain and inadequate response or intolerance to other treatments. Oral nefopam and oromucosal cannabis have more significant side effect profiles however and the potential harms seem to outweigh any modest benefit achieved.

Source:Cochrane Library.

 

 

 

Muscle relaxants for pain management in rheumatoid arthritis,

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Pain management is a high priority for patients with rheumatoid arthritis (RA). Muscle relaxants include drugs that reduce muscle spasm (for example benzodiazepines such as diazepam (Valium), alprazolam (Xanax), lorazepam (Ativan) and non-benzodiazepines such as metaxalone (Skelaxin) or a combination of paracetamol and orphenadrine (Muscol)) and drugs that prevent increased muscle tone (baclofen and dantrolene). Despite a paucity of evidence supporting their use, antispasmodic and antispasticity muscle relaxants have gained widespread clinical acceptance as adjuvants in the management of patients with chronic musculoskeletal pain.

Objectives

The aim of this review was to determine the efficacy and safety of muscle relaxants in pain management in patients with RA. The muscle relaxants that were included in this review are the antispasmodic benzodiazepines (alprazolam, bromazepam, chlordiazepoxide,cinolazepam, clonazepam, cloxazolam, clorazepate, diazepam, estazolam, flunitrazepam, flurazepam, flutoprazepam, halazepam, ketazolam, loprazolam, lorazepam, lormetazepam, medazepam, midazolam, nimetazepam, nitrazepam, nordazepam, oxazepam, pinazepam, prazepam, quazepam, temazepam, tetrazepam, triazolam), antispasmodic non-benzodiazepines (cyclobenzaprine, carisoprodol, chlorzoxazone, meprobamate, methocarbamol, metaxalone, orphenadrine, tizanidine and zopiclone), and antispasticity drugs (baclofen and dantrolene sodium).

Search methods

We performed a search of the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, 4th quarter 2010), MEDLINE (1950 to week 1 November 2010), EMBASE (Week 44 2010), and PsycINFO (1806 to week 2 November 2010). We also searched the 2008 to 2009 American College of Rheumatology (ACR) and European League Against Rheumatism (EULAR) abstracts and performed a handsearch of reference lists of relevant articles.

Selection criteria

We included randomised controlled trials which compared a muscle relaxant to another therapy (active, including non-pharmacological therapies, or placebo) in adult patients with RA and that reported at least one clinically relevant outcome.

Data collection and analysis

Two blinded review authors independently extracted data and assessed the risk of bias in the trials. Meta-analyses were used to examine the efficacy of muscle relaxants on pain, depression, sleep and function, as well as their safety.

Main results

Six trials (126 participants) were included in this review. All trials were rated at high risk of bias. Five cross-over trials evaluated a benzodiazepine, four assessed diazepam (n = 71) and one assessed triazolam (n = 15). The sixth trial assessed zopiclone (a non-benzodiazepine) (n = 40) and was a parallel group study. No trial duration was longer than two weeks while three single dose trials assessed outcomes at 24 hours only. Overall the included trials failed to find evidence of a beneficial effect of muscle relaxants over placebo, alone (at 24 hrs, 1 or 2 weeks) or in addition to non-steroidal anti-inflammatory drugs (NSAIDs) (at 24 hrs), on pain intensity, function, or quality of life. Data from two trials of longer than 24 hours duration (n = 74) (diazepam and zopiclone) found that participants who received a muscle relaxant had significantly more adverse events compared with those who received placebo (number needed to harm (NNTH) 3, 95% CI 2 to 7). These were predominantly central nervous system side effects, including dizziness and drowsiness (NNTH 3, 95% CI 2 to 11).

Authors’ conclusions

Based upon the currently available evidence in patients with RA, benzodiazepines (diazepam and triazolam) do not appear to be beneficial in improving pain over 24 hours or one week. The non-benzodiazepine agent zopiclone also did not significantly reduce pain over two weeks. However, even short term muscle relaxant use (24 hours to 2 weeks) is associated with significant adverse events, predominantly drowsiness and dizziness.

Source:Cochrane Library.

 

 

Small molecule inhibitors of ezrin inhibit the invasive phenotype of osteosarcoma cells .

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Ezrin is a multifunctional protein that connects the actin cytoskeleton to the extracellular matrix through transmembrane proteins. High ezrin expression is associated with lung metastasis and poor survival in cancer. We screened small molecule libraries for compounds that directly interact with ezrin protein using surface plasmon resonance to identify lead compounds. The secondary functional assays used for lead compound selection included ezrin phosphorylation as measured by immunoprecipitation and in vitro kinase assays, actin binding, chemotaxis, invasion into an endothelial cell monolayer, zebrafish and Xenopus embryonic development, mouse lung organ culture and an in vivo lung metastasis model. Two molecules, NSC305787 and NSC668394, that directly bind to ezrin with low micromolar affinity were selected based on inhibition of ezrin function in multiple assays. They inhibited ezrin phosphorylation, ezrin–actin interaction and ezrin-mediated motility of osteosarcoma (OS) cells in culture. NSC305787 mimicked the ezrin morpholino phenotype, and NSC668394 caused a unique developmental defect consistent with reduced cell motility in zebrafish. Following tail vein injection of OS cells into mice, both molecules inhibited lung metastasis of ezrin-sensitive cells, but not ezrin-resistant cells. The small molecule inhibitors NSC305787 and NSC668394 demonstrate a novel targeted therapy that directly inhibits ezrin protein as an approach to prevent tumor metastasis.

Source:Oncogene.

 

 

The antitumor effects of adenoviral-mediated, intratumoral delivery of interleukin 23 require endogenous IL-12 .

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Interleukin (IL)-23 is a member of the IL-12 family of heterodimeric cytokines, comprised of p19 and p40 subunits, which exhibits immunostimulatory properties similar to IL-12. We have demonstrated previously that adenoviral-mediated, intratumoral delivery of IL-23 (Ad.IL-23) was able to induce systemic antitumor immunity. Here we demonstrate that Ad.IL-23 requires endogenous IL-12 for conferring an antitumor effect after adenoviral-mediated, intratumoral delivery. In contrast, Ad.IL-12 does not require IL-23 for its antitumor effects although endogenous IL-23 appears important for induction of systemic antitumor immunity by IL-12. However, despite the requirement for endogenous IL-12, co-delivery of IL-23 and IL-12 does not provide even an additive local or systemic antitumor effect, regardless of the dose. We further demonstrate that although the use of a single-chain IL-23 (scIL-23) results in higher level of expression and a more pronounced IL-23-mediated antitumor effect, there is still no synergy with IL-12. These results demonstrate that although significant antitumor effects are achieved by intratumoral injection of adenovirus expressing either scIL-23 or IL-12 alone and that IL-23 requires endogenous IL-12 for maximum antitumor benefit, the combined use of these cytokines provides no additive or synergistic effect.

Source:Cancer Gene Therapy

 

Tumor-targeted gene therapy using Adv-AFP-HRPC/IAA prodrug system suppresses growth of hepatoma xenografted in mice.

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Clinical efficacy of current therapies for hepatocellular carcinoma (HCC) treatment is limited. Indole-3-acetic acid (IAA) is non-toxic for mammalian cells. Oxidative decarboxylation of IAA by horseradish peroxidase (HRP) leads to toxic effects of IAA. The purpose of this study was to investigate the effects of a novel gene-targeted enzyme prodrug therapy with IAA on hepatoma growth in vitro and in vivo mouse hepatoma models. We generated a plasmid using adenovirus to express HRP isoenzyme C (HRPC) with the HCC marker, alpha-fetoprotein (AFP), as the promoter (pAdv-AFP-HRPC). Hepatocellular cells were infected with pAdv-AFP-HRPC and treated with IAA. Cell death was detected using MTT assay. Hepatoma xenografts were developed in mice by injection of mouse hepatoma cells. The size and weight of tumors and organs were evaluated. Cell death in tumors was assessed using hematoxylin and eosin-stained tissue sections. HRPC expression in tissues was detected using Reverse Transcriptase-Polymerase Chain Reaction. IAA stimulated death of hepatocellular cells infected with pAdv-AFP-HRPC, in a dose- and time-dependent manner, but not in control cells. Growth of hepatoma xenografts, including the size and weight, was inhibited in mice treated with pAdv-AFP-HRPC and IAA, compared with that in control group. pAdv-AFP-HRPC/IAA treatment induced cell death in hepatoma xenografts in mice. HRPC gene expressed only in hepatoma, but not in other normal organs of mice. pAdv-AFP-HRPC/IAA treatment did not cause any side effects on normal organs. These findings suggest that pAdv-AFP-HRPC/IAA enzyme/prodrug system may serve as a strategy for HCC therapy.

Source:Cancer Gene Therapy.

 

Effects of glucagon-like peptide-1 receptor agonists on weight loss: systematic review and meta-analyses of randomised controlled trials .

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Objective To determine whether treatment with agonists of glucagon-like peptide-1 receptor (GLP-1R) result in weight loss in overweight or obese patients with or without type 2 diabetes mellitus.

Design Systematic review with meta-analyses.

Data sources Electronic searches (Cochrane Library, Medline, Embase, and Web of Science) and manual searches (up to May 2011).

Review methods Randomised controlled trials of adult participants with a body mass index of 25 or higher; with or without type 2 diabetes mellitus; and who received exenatide twice daily, exenatide once weekly, or liraglutide once daily at clinically relevant doses for at least 20 weeks. Control interventions assessed were placebo, oral antidiabetic drugs, or insulin.

Data extraction Three authors independently extracted data. We used random effects models for the primary meta-analyses. We also did subgroup, sensitivity, regression, and sequential analyses to evaluate sources of intertrial heterogeneity, bias, and the robustness of results after adjusting for multiple testing and random errors.

Results 25 trials were included in the analysis. GLP-1R agonist groups achieved a greater weight loss than control groups (weighted mean difference −2.9 kg, 95% confidence interval –3.6 to –2.2; 21 trials, 6411 participants). We found evidence of intertrial heterogeneity, but no evidence of bias or small study effects in regression analyses. The results were confirmed in sequential analyses. We recorded weight loss in the GLP-1R agonist groups for patients without diabetes (–3.2 kg, –4.3 to –2.1; three trials) as well as patients with diabetes (–2.8 kg, –3.4 to –2.3; 18 trials). In the overall analysis, GLP-1R agonists had beneficial effects on systolic and diastolic blood pressure, plasma concentrations of cholesterol, and glycaemic control, but did not have a significant effect on plasma concentrations of liver enzymes. GLP-1R agonists were associated with nausea, diarrhoea, and vomiting, but not with hypoglycaemia.

Conclusions The present review provides evidence that treatment with GLP-1R agonists leads to weight loss in overweight or obese patients with or without type 2 diabetes mellitus.

Source:BMJ.

 

 

 

Timing of onset of cognitive decline: results from Whitehall II prospective cohort study.

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To estimate 10 year decline in cognitive function from longitudinal data in a middle aged cohort and to examine whether age cohorts can be compared with cross sectional data to infer the effect of age on cognitive decline.

Design Prospective cohort study. At study inception in 1985-8, there were 10 308 participants, representing a recruitment rate of 73%.

Setting Civil service departments in London, United Kingdom.

Participants 5198 men and 2192 women, aged 45-70 at the beginning of cognitive testing in 1997-9.

Main outcome measure Tests of memory, reasoning, vocabulary, and phonemic and semantic fluency, assessed three times over 10 years.

Results All cognitive scores, except vocabulary, declined in all five age categories (age 45-49, 50-54, 55-59, 60-64, and 65-70 at baseline), with evidence of faster decline in older people. In men, the 10 year decline, shown as change/range of test×100, in reasoning was −3.6% (95% confidence interval −4.1% to −3.0%) in those aged 45-49 at baseline and −9.6% (−10.6% to −8.6%) in those aged 65-70. In women, the corresponding decline was −3.6% (−4.6% to −2.7%) and −7.4% (−9.1% to −5.7%). Comparisons of longitudinal and cross sectional effects of age suggest that the latter overestimate decline in women because of cohort differences in education. For example, in women aged 45-49 the longitudinal analysis showed reasoning to have declined by −3.6% (−4.5% to −2.8%) but the cross sectional effects suggested a decline of −11.4% (−14.0% to −8.9%).

Conclusions Cognitive decline is already evident in middle age (age 45-49).

Source:BMJ.

 

The greening of medicine.

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Three days after his kidney transplantation, saxophonist Andy Williamson was performing an impromptu lunchtime concert in the atrium at Guy’s Hospital in London, accompanied by a piano player who also happened to be the donor. The dynamic duo were even doing requests, playing Take the A-Train for one of their surgeons.1 Still a successful jazz musician, Williamson has embarked on another line of work in the years since his transplant operation: he’s at the cutting edge of a new form of patient activism that is pushing the public, professionals, and policy makers for an urgent and comprehensive greening of medicine.

“Having kidney failure suddenly brings you into uncomfortable proximity with our disposable culture,” says Mr Williamson, who developed end stage kidney failure in early 2006. A turning point came when he started dialysis at home, and a lorry would arrive regularly with a palette full of plastic and cardboard to be used once and then thrown away. “In a household geared to recycling and minimising packaging it was all a bit of a shock.” Well aware that an ultra-cautious culture has driven a lot of the excess for good safety reasons, Mr Williamson, like others pushing for a sustainable health system, has become increasingly convinced of the need for change, and the possibility that it can come without doing harm. “There is so much unthinking waste that happens in hospitals, as it does in our everyday lives,” says Mr Williamson. “It’s just that it’s writ large in the healthcare system.”

Source:BMJ.

Selective serotonin reuptake inhibitors during pregnancy and risk of persistent pulmonary hypertension in the newborn: population based cohort study from the five Nordic countries.

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Objective To assess whether maternal use of selective serotonin reuptake inhibitors (SSRIs) increases the risk of persistent pulmonary hypertension in the newborn, and whether such an effect might differ between specific SSRIs.

Design Population based cohort study using data from the national health registers.

Setting Denmark, Finland, Iceland, Norway, and Sweden, 1996-2007.

Participants More than 1.6 million infants born after gestational week 33.

Main outcome measures Risks of persistent pulmonary hypertension of the newborn associated with early and late exposure to SSRIs during pregnancy and adjusted for important maternal and pregnancy characteristics. Comparisons were made between infants exposed and not exposed to SSRIs.

Results Around 30 000 women had used SSRIs during pregnancy and 11 014 had been dispensed an SSRI later than gestational week 20. Exposure to SSRIs in late pregnancy was associated with an increased risk of persistent pulmonary hypertension in the newborn: 33 of 11 014 exposed infants (absolute risk 3 per 1000 liveborn infants compared with the background incidence of 1.2 per 1000); adjusted odds ratio 2.1 (95% confidence interval 1.5 to 3.0). The increased risks of persistent pulmonary hypertension in the newborn for each of the specific SSRIs (sertraline, citalopram, paroxetine, and fluoxetine) were of similar magnitude. Filling a prescription with SSRIs before gestational week 8 yielded slightly increased risks: adjusted odds ratio 1.4 (95% confidence interval 1.0 to 2.0).

Conclusions The risk of persistent pulmonary hypertension of the newborn is low, but use of SSRIs in late pregnancy increases that risk more than twofold. The increased risk seems to be a class effect.

Source:BMJ.