The PATCH trial: efficacy and safety of 5% lidocaine-medicated plaster for the treatment of patients with trigeminal neuralgia: a study protocol for a multicentric, double-blind, enriched enrolment randomised withdrawal, vehicle-controlled study

IntroductionTrigeminal neuralgia (TN) is characterised by a sudden, severe, electric shock like paroxysmal pain, which is almost always associated with triggers. Carbamazepine is the first-line medical management of TN. However, side effects are common. Currently, there is no ideal treatment for TN. Since there is a known abnormality of Na+ channels in the trigger zone, 5% lidocaine-medicated plaster (LMP), which can block the Na+ channels on Aδ and C fibres, is an effective treatment method in many chronic pain conditions. A case report has found the benefit of LMP for the treatment of TN without any side effects. Whether LMP is an option for the treatment of TN is worth exploring.Methods and analysisThe PATCH trial is a double-blind, enriched enrolment with randomised withdrawal, vehicle-controlled trial, aiming to explore the effects and safety of LMP in patients with TN. There is a 3-week initial open-label phase, followed by a 4-week double-blind treatment phase for responders. In the double-blind phase, patients will have to withdraw from this PATCH study if they meet one of the following criteria for treatment failure such as: >50% increase in pain intensity or paroxysms, lack of efficacy or side effects. The primary outcome will be the number of treatment failures. Adverse events will also be monitored throughout the study.Ethics and disseminationThis study protocol has been approved by the Institutional Review Board of Beijing Tiantan Hospital (approval number: KY 2020-102-02). The results will be disseminated in international academic meetings and published in peer-reviewed journals.Trial registration numberNCT04570293.

Accessing routinely collected health data to improve clinical trials: recent experience of access

Background Routinely collected electronic health records (EHRs) have the potential to enhance randomised controlled trials (RCTs) by facilitating recruitment and follow-up. Despite this, current EHR use is minimal in UK RCTs, in part due to ongoing concerns about the utility (reliability, completeness, accuracy) and accessibility of the data. The aim of this manuscript is to document the process, timelines and challenges of the application process to help improve the service both for the applicants and data holders. Methods This is a qualitative paper providing a descriptive narrative from one UK clinical trials unit (MRC CTU at UCL) on the experience of two trial teams’ application process to access data from three large English national datasets: National Cancer Registration and Analysis Service (NCRAS), National Institute for Cardiovascular Outcomes Research (NICOR) and NHS Digital to establish themes for discussion. The underpinning reason for applying for the data was to compare EHRs with data collected through case report forms in two RCTs, Add-Aspirin (ISRCTN 74358648) and PATCH (ISRCTN 70406718). Results The Add-Aspirin trial, which had a pre-planned embedded sub-study to assess EHR, received data from NCRAS 13 months after the first application. In the PATCH trial, the decision to request data was made whilst the trial was recruiting. The study received data after 8 months from NICOR and 15 months for NHS Digital following final application submission. This concluded in May 2020. Prior to application submission, significant time and effort was needed particularly in relation to the PATCH trial where negotiations over consent and data linkage took many years. Conclusions Our experience demonstrates that data access can be a prolonged and complex process. This is compounded if multiple data sources are required for the same project. This needs to be factored in when planning to use EHR within RCTs and is best considered prior to conception of the trial. Data holders and researchers are endeavouring to simplify and streamline the application process so that the potential of EHR can be realised for clinical trials.

Inter-rater reliability of care home staff’s proxy judgements with residents’ assessments of their own health-related quality of life: an analysis of the PATCH trial EQ-5D data

Objectives to compare care staff proxies with care home residents’ self-assessment of their health-related quality of life (HRQoL). Methods we assessed the degree of inter-rater reliability between residents and care staff proxies for the EQ-5D-5L index, domains and EQ Visual Analogue Scale at baseline, 3 months and 6 months, collected as part of the PATCH trial. We calculated kappa scores. Interpreted as <0 no agreement, 0–0.2 slight, 0.21–0.60 fair to moderate and >0.6 substantial to almost perfect agreement. Qualitative interviews with care staff and researchers explored the challenges of completing these questions. Results over 50% of the HRQoL data from residents was missing at baseline compared with a 100% completion rate by care staff proxies. A fair-to-moderate level of agreement was found for the EQ-5D-5L index. A higher level of agreement was achieved for the EQ-5D-5L domains of mobility and pain. Resident ‘non-completers’ were more likely to: be older, have stayed a longer duration in the care home, have lower Barthel Index and Physical Activity and Mobility in Residential Care (PAM-RC) scores, a greater number of co-morbidities and have joined the trial through consultee agreement. Interviews with staff and researchers indicated that it was easier to rate residents’ mobility levels than other domains, but in general it was difficult to obtain data from residents or to make an accurate proxy judgement for those with dementia. Conclusions whilst assessing HRQoL by care staff proxy completion provides a more complete dataset, uncertainty remains as to how representative these values are for different groups of residents within care homes.

PATCHing platelet data to improve transfusion

The Platelet Transfusion in Cerebral Hemorrhage (PATCH) trial, a trial of platelet transfusion in patients on antiplatelet agents with cerebral hemorrhage, suggested that platelets worsened outcomes. Reanalysis of the data by the investigators revealed that despite randomization, some, if not all, of the adverse effects of platelets reflected worse baseline hemorrhage in patients in the platelet arm.