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Chronic rejection is the single biggest cause of premature kidney graft failure. HLA antibodies (Ab) are an established prognostic biomarker for premature graft failure so there is a need to test whether treatment decisions based on the presence of the biomarker can alter prognosis. The Optimised TacrolimuS and MMF for HLA Antibodies after Renal Transplantation (OuTSMART) trial combines two elements. Firstly, testing whether a routine screening programme for HLA Ab in all kidney transplant recipients is useful by comparing blinding versus unblinding of HLA Ab status. Secondly, for those found to be HLA Ab+, testing whether the introduction of a standard optimisation treatment protocol can reduce graft failure rates. OuTSMART is a prospective, open-labelled, randomised biomarker-based strategy (hybrid) trial, with two arms stratified by biomarker (HLA Ab) status. The primary outcome was amended from graft failure rates at 3 years to time to graft failure to increase power and require fewer participants to be recruited. Length of follow-up subsequently is variable, with all participants followed up for at least 43 months up to a maximum of 89 months. The primary outcome will be analysed using Cox regression adjusting for stratification factors. Analyses will be according to the intention-to-treat using all participants as randomised. Outcomes will be analysed comparing standard care versus biomarker-led care groups within the HLA Ab+ participants (including those who become HLA Ab+ through re-screening) as well as between HLA-Ab-unblinded and HLA-Ab-blinded groups using all participants. Changes to the primary outcome permit recruitment of fewer participants to achieve the same statistical power. Pre-stating the statistical analysis plan guards against changes to the analysis methods at the point of analysis that might otherwise introduce bias through knowledge of the data. Any deviations from the analysis plan will be justified in the final report. ISRCTN registry, ID: ISRCTN46157828 . Registered on 26 March 2013; EudraCT 2012–004308-36 . Registered on 10 December 2012.

The initial therapy for a stenosis in an arteriovenous fistula used for haemodialysis is radiological balloon dilatation or angioplasty. The benefit of angioplasty is often short-lived, intervention-free survival is reported to be 40–50 % at 1 year. Previous small studies and observational data suggest that paclitaxel-coated balloons may be of benefit in improving outcomes after fistuloplasty of stenotic arteriovenous fistulae. We have designed a multicentre, double-blind randomised controlled trial to test the superiority of paclitaxel-coated balloons for preventing restenosis after fistuloplasty in patients with a native arteriovenous fistula. Two hundred and eleven patients will be followed up for a minimum of 1 year. Inclusion criteria include a clinical indication for a fistuloplasty, an access circuit that is free of synthetic graft material or stents, and a residual stenosis of 30 % or less after plain balloon fistuloplasty. Exclusion criteria include a synchronous venous lesion in the same access circuit, location of the stenosis central to the thoracic inlet or a thrombosed access circuit at the time of treatment. The primary endpoint is time to end of target lesion primary patency. This is defined as a clinically-driven radiological or surgical re-intervention at the treatment segment, thrombosis that includes the treatment segment, or abandonment of the access circuit due to an inability to re-treat the treatment segment. Secondary endpoints include angiographic late lumen loss, time to end of access circuit cumulative patency, the total number of interventions, and quality of life. The trial is funded by the National Institute for Health Research. We anticipate that this trial will provide rigorous data that will determine the efficacy of additional paclitaxel-coated balloon fistuloplasty versus plain balloon fistuloplasty only to preserve the patency of arteriovenous fistulae used for haemodialysis. ISRCTN14284759 . Registered on 28 October 2015.

Background Early identification of participants at risk of run-in failure (RIF) may present opportunities to improve trial efficiency and generalizability. Methods We conducted a partial factorial-design, randomized, controlled trial of calcium and vitamin D to prevent colorectal adenoma recurrence at 11 centers in the United States. At baseline, participants completed two self-administered questionnaires (SAQs) and a questionnaire administered by staff. Participants in the full factorial randomization (calcium, vitamin D, both, or neither) received a placebo during a 3-month single-blinded run-in; women electing to take calcium enrolled in a two-group randomization (calcium with vitamin D, or calcium alone) and received calcium during the run-in. Using logistic regression models, we examined baseline factors associated with RIF in three subgroups: men (N = 1606) and women (N = 301) in the full factorial randomization and women in the two-group randomization (N = 666). Results Overall, 314/2573 (12 %) participants failed run-in; 211 (67 %) took fewer than 80 % of their tablets (poor adherence), and 103 (33 %) withdrew or were uncooperative. In multivariable models, 8- to 13-fold variation was seen by study center in odds of RIF risk in the two largest groups. In men, RIF decreased with age (adjusted odds ratio [OR] per 5 years 0.85 [95 % confidence interval, CI; 0.76–0.96]) and was associated with being single (OR 1.65 [95 % CI; 1.10–2.47]), not graduating from high school (OR 2.77 [95 % CI; 1.58–4.85]), and missing SAQ data (OR 1.97 [1.40–2.76]). Among women, RIF was associated primarily with health-related factors; RIF risk was lower with higher physical health score (OR 0.73 [95 % CI; 0.62–0.86]) and baseline multivitamin use (OR 0.44 [95 % CI; 0.26–0.75]). Women in the 5-year colonoscopy surveillance interval were at greater risk of RIF than those with 3-year follow-up (OR 1.91 [95 % CI; 1.08–3.37]), and the number of prescription medicines taken was also positively correlated with RIF (p = 0.03). Perceived toxicities during run-in were associated with 12- to 29-fold significantly increased odds of RIF. Conclusions There were few common baseline predictors of run-in failure in the three randomization groups. However, heterogeneity in run-in failure associated with study center, and missing SAQ data reflect potential opportunities for intervention to improve trial efficiency and retention. Trial registration ClinicalTrials.gov: NCT00153816. Registered September 2005. Electronic supplementary material The online version of this article (doi:10.1186/s13063-016-1451-9) contains supplementary material, which is available to authorized users.

Good information on drug harm is vital to inform riskbenefit decisions and undertake robust cost effectiveness analysis. Harm information in peer-reviewed articles have been found not to be useful for this purpose. Regulators require pharmaceutical companies to produce product information documents (Europe:SmPC, US: USPI). These documents contain comprehensive information on the known harm of a drug. We reviewed the usefulness of the data and compared the harm profile for brand drugs marketed in Europe and the US. This review included 12 antidepressants/antiepileptic brand drugs (SmPC and USPI). On average 77 more adverse reactions (ARs) were reported in the USPI compared to the SmPC document. The median number of ARs included were SPC:114 (IQR 93,150) and USPI:201 (IQR 114, 262). In clinical trials many adverse events (AEs) will be reported for each treatment. In order to identify ARs from all the AEs reported during the trial, a criterion or rule is often used. Nine USPIs and 3 SmPC reported the criterion used, but this was not the same in the 3 paired documents and in 7 USPIs multiple criterion were used. It is expected that the harm profile in the product information for the same drug should agree. This review found a lack of consistency for the same drug and demonstrates the overwhelming impact of arbitrary rules used for reporting. This problem can only be exacerbated across drugs. The development of CORE harm outcome sets by drug class would facilitate comparison of harm profiles across drug and support informed risk-benefit decisions. Authors’ details King’s College London, London, UK. University of Bielefeld, Bielefeld, Germany.

Background In RCTs with a continuous outcome, it is easier to interpret a difference in proportions at high risk than the difference in means. For example when comparing lung function in two groups, a difference in proportion

Objectives Dichotomizing continuous data prior to analysis is rarely a good idea as power is lost. However expressing results as a difference of means is not always meaningful for clinicians; small differences in means may seem clinically unimportant while the same study results expressed as a difference/ratio of proportions or number needed to treat might reveal an effect that is considered worthwhile. We therefore sought an estimate based on comparing proportions that gives the same p value as the corresponding comparison of means.

Background Monitoring the safety of therapies is of paramount importance in protecting patients from harm and enabling risk-benefit assessment. The recording and reporting of measures of efficacy has received considerable attention and while by no means perfect, has advanced further than the parallel assessment of harm. The stimulus for this study came from a commissioned effectiveness and cost-effectiveness review of treatments for neuropathic pain in patients (the CEAN study) [1]. CEAN noted that the completeness of adverse event (AE) reporting varied between trials and some expert opinion was required where primary data were insufficient for modeling cost-effectiveness. Further, clinicians indicated that trials sometimes failed to provide adequate information for clinical decision-making and informing patients.

BACKGROUND: The standard of care for neovascular age-related macular degeneration (nAMD) involves ongoing intravitreal injections of anti-angiogenic drugs targeting vascular endothelial growth factor (VEGF). The most commonly used anti-VEGF drugs are ranibizumab, bevacizumab and aflibercept. The main objective of the STAR trial is to determine if stereotactic radiotherapy can reduce the number of anti-VEGF injections that patients with nAMD require.METHODS/DESIGN: STAR is a multicentre, double-masked, randomised, sham-controlled clinical trial. It evaluates a new device (manufactured by Oraya, Newark, CA, USA) designed to deliver stereotactic radiotherapy (SRT) to nAMD lesions. The trial enrols participants with chronic, active nAMD. Participants receive a single SRT treatment (16 Gy or sham) with a concomitant baseline intravitreal injection of 0.5 mg ranibizumab. Thereafter, they attend every month for 24 months, and ranibizumab is administered at the visit if retreatment criteria are met. The primary outcome is the number of pro re nata ranibizumab injections during the first 24 months. Secondary outcomes include visual acuity, lesion morphology, quality of life and safety. Additional visits occur at 36 and 48 months to inspect for radiation retinopathy. The target sample size of 411 participants (randomised 2:1 in favour of radiation) is designed to detect a reduction of 2.5 injections against ranibizumab monotherapy, at 90% power, and a significance level (alpha) of 0.025 (one-sided two-sample t test). This gives 97% power to detect non-inferiority of visual acuity at a five-letter margin. The primary analyses will be by intention to treat.DISCUSSION: The safety and efficacy outcomes will help determine the role of SRT in the management of chronic, active nAMD.TRIAL REGISTRATION: International Standard Randomised Controlled Trial Number: ISRCTN12884465. Registered on 28 November 2014. ClinicalTrials.gov: NCT02243878 . Registered on 17 September 2014.

Background Good information on the harm of a drug is vital to inform risk-benefit decisions and undertake robust cost effectiveness analysis. Clinical trials reported in peerreviewed articles are not useful for this purpose [1,2]. Regulators require pharmaceutical companies to produce product information documents (Europe:SmPC, US:USPI). These documents contain comprehensive and valuable publicly available information on the known harm of a drug and have the potential to inform important risk-benefit decisions. We reviewed the usefulness of the data presented and compared the harm profile reported in documents for brand drugs marketed in Europe and the US.