Validation of the GetReal Trial Tool - Facilitating discussion and understanding more pragmatic design choices and their implications.

BACKGROUND: The GetReal Trial Tool is a decision support tool to assess the impact of design choices on generalizability of clinical trials to routine clinical practice, while taking into account the risk of bias, precision, acceptability and operational feasibility. This study describes the validation of the GetReal Trial Tool. METHODS: Twelve experts took part in the GetReal Trial tool validation using the protocols of 6 trials conducted with pragmatic elements. The tool entails 7 domains with a total of 43 questions. A pooled Kappa statistic (95% CI) using random effects model was estimated using Open Meta (analyst) software. The possible operational challenges were collated and discussed with the trialists that conducted the trials. RESULTS: Agreement in the design choices made for the trial protocols was >50% for all the trials and all teams reached consensus during discussion. The pooled Kappa statistic (95% CI) was 0.236 (0.154-0.318). The GetReal Trial tool highlighted several operational challenges, of which almost half had been experienced previously by the trialists. Out of 25 additional operational challenges mentioned by the trialists, 76% were already highlighted by the tool. The tool was considered helpful to optimize trials right from the design stage. CONCLUSION: The GetReal Trial Tool helps to scrutinize the choice of study design in the light of Real World Evidence generation. The tool identifies most of the operational challenges experienced by trialists to date. The tool serves the intended purpose of facilitating discussion and understanding more pragmatic design choices and their implications.

The GetReal Trial Tool: design, assess and discuss clinical drug trials in light of Real World Evidence generation.

Methodologies incorporating Real World Elements into clinical trial design (also called pragmatic trials) offer an attractive opportunity to assess the effect of a treatment strategy in routine care and as such guide decision making in practice. Uptake of these methods is slow for several reasons, including uncertainty about acceptability of trial results, lack of experience with the methodology and operational challenges. We developed the "GetReal Trial Tool," an easy-to-use online interface, which allows users to assess the impact of design choices on generalizability to routine clinical practice, while taking into account risk of bias, precision, acceptability and operational feasibility. The tool is grounded in the scientific literature combined with knowledge of experts from academia, pharmaceutical companies, HTA bodies, patient organizations, and regulators. The aim is to help researchers optimize trial design and facilitate translation of evidence from pragmatic trials to clinical practice. In this paper we describe the development, structure and application of the GetReal Trial Tool.

Effectiveness and safety of rivaroxaban vs. warfarin in patients with non-valvular atrial fibrillation and coronary or peripheral artery disease.

AIMS: There are scarce data evaluating the effectiveness and safety of rivaroxaban vs. warfarin in non-valvular atrial fibrillation (NVAF) patients with concomitant coronary artery disease (CAD) and/or peripheral artery disease (PAD) treated in routine practice. METHODS AND RESULTS: Using MarketScan data from January 2012 to December 2017, we identified oral anticoagulant (OAC)-naïve NVAF patients receiving rivaroxaban (15-20 mg once daily) or warfarin, with comorbid CAD and/or PAD and ≥12 months of insurance coverage before OAC initiation. Differences in baseline covariates between cohorts were adjusted using inverse probability-of-treatment weights based on propensity scores (standardized differences <0.1 achieved for all covariates after adjustment). Endpoints included a composite of major thrombotic vascular events (MTVEs) (including ischaemic stroke, myocardial infarction, or need for lower limb revascularization/major amputation) and major bleeding. Patients were followed until an event-of-interest, discontinuation/switch of index OAC, insurance disenrolment, or end-of-data availability. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated using Cox regression. We identified 3257 rivaroxaban (30.4% received a 15 mg dose) and 5046 warfarin users with NVAF and comorbid CAD and/or PAD. Rivaroxaban was associated with a 32% (95% CI = 8-50%) reduction in the composite of MTVE. No significant difference in major bleeding was observed (HR = 1.13, 95% CI = 0.84-1.52). No statistical interactions were noted in subgroup analyses performed on the MTVE (P-interaction ≥ 0.35 for all) or major bleeding endpoints (P-interaction ≥ 0.09 for all). CONCLUSION: Among patients with NVAF and comorbid CAD and/or PAD, rivaroxaban use was associated with a reduced risk of MTVEs vs. warfarin, without significantly increasing major bleeding risk.

Rivaroxaban vs. warfarin and renal outcomes in non-valvular atrial fibrillation patients with diabetes.

AIMS: Vascular calcification is common in diabetic patients. Warfarin has been associated with renovascular calcification and worsening renal function; rivaroxaban may provide renopreservation by decreasing vascular inflammation. We compared the impact of rivaroxaban and warfarin on renal outcomes in diabetic patients with non-valvular atrial fibrillation (NVAF). METHODS AND RESULTS: Using United States IBM MarketScan data from January 2011 to December 2017, we identified adults with both NVAF and diabetes, newly-initiated on rivaroxaban or warfarin with ≥12-month insurance coverage prior to anticoagulation initiation. Patients with Stage 5 chronic kidney disease (CKD) or undergoing haemodialysis at baseline were excluded. Differences in baseline covariates between cohorts were adjusted using inverse probability-of-treatment weighting (IPTW) based on propensity scores (absolute standardized differences <0.1 achieved for all after adjustment). Outcomes included incidence rates of emergency department/hospital admissions for acute kidney injury (AKI) and the composite of the development of Stage 5 CKD or need for haemodialysis. Patients were followed until an event, index anticoagulant discontinuation/switch, insurance disenrollment, or end-of-data availability. Hazard ratios (HRs) with 95% confidence intervals (CIs) were estimated using Cox regression. We assessed 10 017 rivaroxaban (22.6% received a reduced dose) and 11 665 warfarin users. In comparison to warfarin, rivaroxaban was associated with lower risks of AKI (HR = 0.83, 95% CI = 0.74-0.92) and development of Stage 5 CKD or need for haemodialysis (HR = 0.82, 95% CI = 0.70-0.96). Sensitivity and subgroup analyses had similar effects as the base-case analysis. CONCLUSION: Rivaroxaban appears to be associated with lower risks of undesirable renal outcomes vs. warfarin in diabetic NVAF patients.

Rivaroxaban's Impact on Renal Decline in Patients With Nonvalvular Atrial Fibrillation: A US MarketScan Claims Database Analysis.

Warfarin has been associated with renovascular calcification and worsening renal function, whereas rivaroxaban may provide a degree of renopreservation by decreasing vascular inflammation. We sought to compare rivaroxaban and warfarin's impact on renal decline in patients with nonvalvular atrial fibrillation (NVAF) treated in routine practice. Using US MarketScan claims data from January 2012 to December 2017, we identified patients with NVAF newly initiated on rivaroxaban or warfarin with ≥12 months of continuous insurance coverage prior to initiation. Patients with stage 5 chronic kidney disease (CKD) or receiving hemodialysis at baseline were excluded. Outcomes included rates (events/100 person-years) of hospital or emergency department admission for acute kidney injury (AKI) or progression to stage 5 CKD or need for hemodialysis. Differences in baseline covariates between cohorts were adjusted using inverse probability-of-treatment weights based on propensity scores (absolute standardized differences <0.1 achieved for all covariates after adjustment). Patients were followed until an event, anticoagulant discontinuation/switch, insurance disenrollment, or end of data availability. Hazard ratios with 95% confidence intervals (CIs) were estimated using Cox regression. We assessed 36 318 rivaroxaban (19.8% received a dose <20 mg/d) and 36 281 warfarin users. Stages 3 and 4 CKD were present in 5% and 1% of patients at baseline, and proteinuria was present in 2%. Rivaroxaban was associated with a 19% (95% CI = 13%-25%) reduction in the hazard of AKI (rates = 4.91 vs 8.45) and an 18% (95% CI = 9%-26%) reduction in progression to stage 5 CKD or hemodialysis (rates = 2.67 vs 4.12). Rivaroxaban appears associated with lower hazards of undesirable renal end points versus warfarin in patients with NVAF.

Rivaroxaban Versus Warfarin in Patients With Nonvalvular Atrial Fibrillation and Severe Kidney Disease or Undergoing Hemodialysis.

BACKGROUND: Patients with nonvalvular atrial fibrillation with stage 4 or 5 chronic kidney disease or undergoing hemodialysis were excluded from phase III randomized trials of nonvitamin K antagonist oral anticoagulants (NOACs). We sought to evaluate the effectiveness and safety of rivaroxaban compared with warfarin in patients with nonvalvular atrial fibrillation and stage 4 or 5 chronic kidney disease or undergoing hemodialysis in routine practice. METHODS: Using MarketScan data from January 2012 to December 2017, we identified patients on oral anticoagulant (OAC) with naïve nonvalvular atrial fibrillation and stage 4 or 5 chronic kidney disease or undergoing hemodialysis and with ≥12 months of insurance coverage before OAC initiation. Differences in baseline covariates between the rivaroxaban and warfarin cohorts were adjusted using inverse probability-of-treatment weights based on propensity scores calculated using generalized boosted models and 10,000 regression trees (absolute standardized differences <0.1 achieved for all covariates after adjustment). Patients were followed until a stroke/systemic embolism or major bleeding event, OAC discontinuation/switch, insurance disenrollment, or end of data availability. Hazard ratios (HRs) and 95% confidence intervals (CIs) comparing the OAC cohorts were calculated using Cox regression. RESULTS: We identified 1896 rivaroxaban (38.7% received a dose <20 mg/d) and 4848 warfarin users. Eighty-eight percent of included patients had stage 5 chronic kidney disease or were undergoing hemodialysis. Rivaroxaban did not significantly reduce stroke or systemic embolism (HR = 0.55, 95% CI = 0.27-1.10) or ischemic stroke (HR = 0.67, 95% CI = 0.30-1.50) alone, but it was associated with a significant 32% (95% CI = 1-53%) reduction in major bleeding risk compared with warfarin. CONCLUSION: Among patients with nonvalvular atrial fibrillation and stage 4 or 5 chronic kidney disease or undergoing hemodialysis, rivaroxaban appears associated with significantly less major bleeding compared to warfarin.

Effectiveness and safety of rivaroxaban and warfarin for prevention of major adverse cardiovascular or limb events in patients with non-valvular atrial fibrillation and type 2 diabetes.

AIMS: To assess the effectiveness and safety of rivaroxaban versus warfarin for the prevention of major adverse cardiovascular events (MACE) and major adverse limb events (MALE) in patients with type 2 diabetes (T2D) and non-valvular atrial fibrillation (NVAF). MATERIALS AND METHODS: Using MarketScan data from January 2012 to December 2017, we identified oral anticoagulant-naïve patients with NVAF and comorbid T2D and ≥12 months of insurance coverage prior to rivaroxaban or warfarin initiation. Differences in baseline covariates between cohorts were adjusted for using inverse probability of treatment weights based on propensity scores (absolute standardized differences <0.1 achieved for all covariates after adjustment). Patients were followed until a MACE, MALE or major bleeding event, oral anticoagulant discontinuation/switch, insurance disenrolment or end of data availability. Hazard ratios (HRs) and 95% confidence intervals (CIs) comparing the cohorts were calculated using Cox regression. RESULTS: We identified 10 700 rivaroxaban users (24.1% received a reduced dose) and 13 946 warfarin users. The median (25%, 75% range) age was 70 (62, 79) years, CHA2DS2-VASc score was 4 (3, 5) and duration of available follow-up was 1.4 (0.6, 2.7) years. Eleven percent of patients had peripheral artery disease, 5.1% had coronary artery disease, and 5.1% had a prior MALE, at baseline. Rivaroxaban was associated with a 25% (95% CI 4-41) reduced risk of MACE and a 63% (95% CI 35-79) reduced risk of MALE compared to warfarin. Major bleeding risk did not significantly differ between cohorts (HR 0.95). CONCLUSIONS: Among patients with NVAF and T2D treated in routine practice, rivaroxaban was associated with lower risks of both MACE and MALE versus warfarin, with no significant difference in major bleeding.

Estimation of the costs attributable to vitamin K antagonist treatment in patients with non-valvular atrial fibrillation from a French societal perspective.

Background: Little is known about the costs associated with vitamin K antagonist (VKA) treatment in patients with non-valvular atrial fibrillation (NVAF) in France. Objectives: To evaluate monthly per-patient costs attributable to VKA treatment in NVAF patients from a French societal perspective. Study design: Retrospective data were obtained from 7 international normalised ratio (INR) monitoring centres in France. Patients older than 18 years of age with NVAF treated with VKA were recruited. Additional patient-level data assessing resource use corresponding with VKA treatment were collected via self-completed questionnaires. Unit costs applicable to 2015 were multiplied by resource use and summed to generate VKA treatment costs. Results: 363 patients were included; 53% were men. The majority of patients received fluindione (72%). The number of INR tests per patient per month was 1.69 (95% CI, 1.59-1.80). The monthly patient cost was €39.72 (€36.23-43.21) from the French societal perspective. Direct medical costs comprised 76% of overall costs, with drug costs representing 7.4% (€2.4); direct non-medical and indirect costs comprised 10% and 14% respectively. Conclusions: Costs associated with VKA treatment in NVAF cannot be estimated only with drug costs. When direct and indirect attributable costs associated with VKA treatment are considered, the VKA treatment costs are more substantial.

Influence of Polypharmacy on the Effectiveness and Safety of Rivaroxaban Versus Warfarin in Patients With Nonvalvular Atrial Fibrillation.

STUDY OBJECTIVE: Patients with nonvalvular atrial fibrillation (NVAF) often have multiple comorbidities requiring concomitant medications in addition to their oral anticoagulant (OAC). The objective of this study was to evaluate the impact of polypharmacy on the effectiveness and safety of rivaroxaban versus warfarin in patients with NVAF managed in routine clinical practice. DESIGN: Retrospective claims analysis. DATA SOURCE: United States Truven MarketScan database (November 2012-March 2017). PATIENTS: Adults who were OAC naïve during the 12 months before the day of the first qualifying rivaroxaban or warfarin dispensing (index date); had at least two International Classification of Diseases, Ninth or Tenth Revision diagnosis codes for atrial fibrillation without codes suggesting valvular heart disease; had at least 12 months of continuous insurance coverage prior to the qualifying OAC dispensing; and were experiencing polypharmacy (concomitant prescription claims for five or more unique chronic medication claims) were included. Patients who had concomitant prescription claims for ≥ 10 unique chronic medication claims constituted the substantial polypharmacy cohort used in the secondary analysis. Patients receiving rivaroxaban were propensity-score matched in a 1:1 ratio to patients receiving warfarin (13,981 patients in each polypharmacy OAC group, and 1765 patients in each substantial polypharmacy OAC group). MEASUREMENTS AND MAIN RESULTS: Patients were followed until occurrence of an event (stroke or systemic embolism [SSE] combined [primary effectiveness outcome] or major bleeding [primary safety outcome]), OAC discontinuation or switch (30-day permissible gap), insurance disenrollment, or end of follow-up period. Rates of SSE, ischemic stroke, and major bleeding were compared by using Cox regression, reported as hazard ratios (HRs) and 95% confidence intervals (CIs). In patients with NVAF taking five or more chronic medications, rivaroxaban was associated with a 34% (95% CI 12-50) and 40% (95% CI 16-57) hazard reduction of SSE and ischemic stroke, respectively. Occurrence of major bleeding was similar between OAC cohorts (HR 1.08, 95% CI 0.92-1.28). A secondary analysis in patients with NVAF with substantial polypharmacy (taking ≥ 10 chronic medications) was also performed. Similar trends in SSE (HR 0.44), ischemic stroke alone (HR 0.62), and major bleeding (HR 1.07) were observed in patients with NVAF who had substantial polypharmacy, although 95% CIs crossed 1.0 for each outcome in this smaller study cohort. CONCLUSION: This real-world study suggests that in the setting of polypharmacy and NVAF, rivaroxaban is an effective and safe alternative to warfarin.

Effectiveness and safety of rivaroxaban vs. warfarin in patients with non-valvular atrial fibrillation and heart failure.

AIMS: Heart failure (HF) is a common co-morbidity in non-valvular atrial fibrillation (NVAF) patients and a potent risk factor for stroke, bleeding, and a decreased time-in-therapeutic range with warfarin. We assessed the real-world effectiveness and safety of rivaroxaban and warfarin in NVAF patients with co-morbid HF. METHODS AND RESULTS: Using US Truven MarketScan Commercial and Medicare supplemental database claims data from 11/2011 to 12/2016, we identified oral anticoagulant (OAC)-naïve NVAF patients with HF (International Classification of Diseases, 10th Revision codes of I50 or I09.81) and ≥12 months of insurance coverage prior to the qualifying OAC dispensing. Rivaroxaban users (20 or 15 mg once daily) were 1:1 propensity score matched to warfarin users, with residual absolute standardized differences <0.1 being achieved for all covariates after matching. Patients were followed up until an event, OAC discontinuation/switch, insurance disenrolment, or end of follow-up. Rates [events per 100 person-years (PYs) of follow-up] for stroke or systemic embolism and major bleeding (using the Cunningham algorithm) were compared between the matched cohorts using Cox proportion hazard regression and reported as hazard ratios (HRs) with 95% confidence intervals (CIs). We matched 3418 rivaroxaban (32% receiving the reduced dose) and 3418 warfarin users with NVAF and HF with a median (interquartile range) available follow-up of 1.4 (0.6, 2.5) years. Median age was 74 (63, 82) years, and median CHA2 DS2 -VASc and HASBLED scores were 4 (3, 5) and 2 (2, 3). Common HF medications included beta-blockers (64%), angiotensin-converting enzyme inhibitors or angiotensin receptor blockers (62%), loop diuretics (46%), digoxin (11%), and aldosterone receptor antagonists (10%). The hazard of developing stroke or systemic embolism (0.98 events/100PY vs. 1.28 events/100PY; HR = 0.82, 95% CI = 0.47-1.44), ischaemic stroke (0.70 events/100PY vs. 1.02 events/100PY; HR = 0.77, 95% CI = 0.41-1.46), or major bleeding (3.86 events/100PY vs. 4.23 events/100PY; HR = 0.98, 95% CI = 0.73-1.31) was not found to be different between rivaroxaban and warfarin users. Intracranial haemorrhage was infrequent in both cohorts and numerically less with rivaroxaban (0.27 events/100PY vs. 0.36 events/100PY; HR = 0.73, 95% CI = 0.25-2.08). CONCLUSIONS: Effectiveness and safety of rivaroxaban vs. warfarin are sustained in NVAF patients with co-morbid HF treated in routine practice. The general consistency between this real-world study and those from phase III randomized trial data of rivaroxaban should provide additional reassurance to clinicians regarding the use of rivaroxaban in NVAF patients with HF.

Patient Preferences for Nonvitamin K Antagonist Oral Anticoagulants in Stroke Prevention: A Multicountry Discrete Choice Experiment.

PURPOSE: The patient's perspective is becoming increasingly important in clinical and policy decisions. This study examined atrial fibrillation (AF) patient preferences for different characteristics of nonvitamin K antagonist oral anticoagulants (NOACs). METHODS: A discrete choice experiment (DCE) addressing AF patients treated with NOACs in France, Germany, and the United Kingdom was conducted. The DCE included the following attributes: frequency of administration (once/twice daily), size of tablet/capsule (6-9 mm/20 mm), meal-related intake (intake with food required/independent), and distance to treating physician (1 km/10 km). Preferences were analyzed based on a conditional logit regression model. RESULTS: In total, 758 patients (males: 57.3%; mean age: 71.4 years) with an average disease duration of 5.5 years were included (apixaban/dabigatran/edoxaban/rivaroxaban: 34.0%/14.5%/6.6%/44.9%, respectively). Patients preferred NOAC treatment options characterized by once-daily dosing regimens (42.8%; p < 0.001), shorter distance to treating physicians (25.0%; p < 0.001), a small-sized tablet (21.5%; p < 0.001), and intake independent of food (10.6%; p < 0.001). CONCLUSIONS: Patients primarily prefer a once-daily NOAC regimen. Individual preferences should be considered for the treatment of AF patients as this may result in improved treatment adherence and consequently better effectiveness and safety in routine clinical practice.

Effectiveness and Safety of Rivaroxaban in Patients With Cancer-Associated Venous Thrombosis.

Background: Although not designated as guideline-recommended first-line anticoagulation therapy, patients are receiving rivaroxaban for the treatment and secondary prevention of cancer-associated venous thrombosis (CAT). We sought to estimate the cumulative incidence of recurrent venous thromboembolism (VTE), major bleeding, and mortality/hospice care in patients with CAT treated with outpatient rivaroxaban in routine practice. Methods: Using US MarketScan claims data from January 2012 through June 2015, we identified adults with active cancer (using SEER program coding) who had ≥1 primary hospitalization or emergency department discharge diagnosis code for VTE (index event) and received rivaroxaban as their first outpatient anticoagulant within 30 days of the index VTE. Patients were required to have ≥180 days of continuous medical/prescription benefits prior to the index VTE. Patients with a previous claim for VTE, atrial fibrillation, or valvular disease or receiving anticoagulation during the baseline period were excluded. We estimated the cumulative incidence with 95% CIs of recurrent VTE, major bleeding, and mortality or need for hospice care at 180 days, assuming competing risks. Results: A total of 949 patients with active cancer were initiated on rivaroxaban following their index VTE. Time from active cancer diagnosis to index CAT was ≤90 days for 27% of patients, 91 to 180 days for 19%, and >180 days for 54%. The mean [SD] age of patients was 62.5 [12.8] years, 43.6% had pulmonary embolism, and metastatic disease was present in 42.6%. During follow-up, there were 37 cases of recurrent VTE, 22 cases of major bleeding (17 gastrointestinal, 3 intracranial, 1 genitourinary, and 1 other bleed), and 105 deaths/hospice claims. The cumulative incidence estimate was 4.0% (95% CI, 2.8%-5.4%) for recurrent VTE, 2.7% (95% CI, 1.7%-4.0%) for major bleeding, and 11.3% (95% CI, 9.2%-13.6%) for mortality/hospice care. Conclusions: Event rates observed in this rivaroxaban-treated cohort were overall consistent with previous studies of patients with rivaroxaban- and warfarin-managed CAT.

Agreement between coding schemas used to identify bleeding-related hospitalizations in claims analyses of nonvalvular atrial fibrillation patients.

BACKGROUND: Schemas to identify bleeding-related hospitalizations in claims data differ in billing codes used and coding positions allowed. We assessed agreement across bleeding-related hospitalization coding schemas for claims analyses of nonvalvular atrial fibrillation (NVAF) patients on oral anticoagulation (OAC). HYPOTHESIS: We hypothesized that prior coding schemas used to identify bleeding-related hospitalizations in claim database studies would provide varying levels of agreement in incidence rates. METHODS: Within MarketScan data, we identified adults, newly started on OAC for NVAF from January 2012 to June 2015. Billing code schemas developed by Cunningham et al., the US Food and Drug Administration (FDA) Mini-Sentinel program, and Yao et al. were used to identify bleeding-related hospitalizations as a surrogate for major bleeding. Bleeds were subcategorized as intracranial hemorrhage (ICH), gastrointestinal (GI), or other. Schema agreement was assessed by comparing incidence, rates of events/100 person-years (PYs), and Cohen's kappa statistic. RESULTS: We identified 151 738 new-users of OAC with NVAF (CHA2DS2-VASc score = 3, [interquartile range = 2-4] and median HAS-BLED score = 3 [interquartile range = 2-3]). The Cunningham, FDA Mini-Sentinel, and Yao schemas identified any bleeding-related hospitalizations in 1.87% (95% confidence interval [CI]: 1.81-1.94), 2.65% (95% CI: 2.57-2.74), and 4.66% (95% CI: 4.55-4.76) of patients (corresponding rates = 3.45, 4.90, and 8.65 events/100 PYs). Kappa agreement across schemas was weak-to-moderate (κ = 0.47-0.66) for any bleeding hospitalization. Near-perfect agreement (κ = 0.99) was observed with the FDA Mini-Sentinel and Yao schemas for ICH-related hospitalizations, but agreement was weak when comparing Cunningham to FDA Mini-Sentinel or Yao (κ = 0.52-0.53). FDA Mini-Sentinel and Yao agreement was moderate (κ = 0.62) for GI bleeding, but agreement was weak when comparing Cunningham to FDA Mini-Sentinel or Yao (κ = 0.44-0.56). For other bleeds, agreement across schemas was minimal (κ = 0.14-0.38). CONCLUSIONS: We observed varying levels of agreement among 3 bleeding-related hospitalizations schemas in NVAF patients.

Series: Pragmatic trials and real world evidence: Paper 8. Data collection and management.

Pragmatic trials can improve our understanding of how treatments will perform in routine practice. In a series of eight papers, the GetReal Consortium has evaluated the challenges in designing and conducting pragmatic trials and their specific methodological, operational, regulatory, and ethical implications. The present final paper of the series discusses the operational and methodological challenges of data collection in pragmatic trials. A more pragmatic data collection needs to balance the delivery of highly accurate and complete data with minimizing the level of interference that data entry and verification induce with clinical practice. Furthermore, it should allow for the involvement of a representative sample of practices, physicians, and patients who prescribe/receive treatment in routine care. This paper discusses challenges that are related to the different methods of data collection and presents potential solutions where possible. No one-size-fits-all recommendation can be given for the collection of data in pragmatic trials, although in general the application of existing routinely used data-collection systems and processes seems to best suit the pragmatic approach. However, data access and privacy, the time points of data collection, the level of detail in the data, and the lack of a clear understanding of the data-collection process were identified as main challenges for the usage of routinely collected data in pragmatic trials. A first step should be to determine to what extent existing health care databases provide the necessary study data and can accommodate data collection and management. When more elaborate or detailed data collection or more structured follow-up is required, data collection in a pragmatic trial will have to be tailor-made, often using a hybrid approach using a dedicated electronic case report form (eCRF). In this case, the eCRF should be kept as simple as possible to reduce the burden for practitioners and minimize influence on routine clinical practice.

Boosting the hypoxic response in myeloid cells accelerates resolution of fibrosis and regeneration of the liver in mice.

We have recently shown that targeting Vascular Endothelial Growth Factor (VEGF) specifically in scar-infiltrating myeloid cells prevented remodeling of the sinusoidal vasculature and abrogated the resolution of murine liver fibrosis, thereby unmasking an unanticipated link between angiogenesis and resolution of fibrosis. In a gain of function approach, we wanted to test the impact of VEGF overexpression in myeloid cells on fibrolysis. We observe that genetic inactivation of the von Hippel Lindau protein (VHL), a negative regulator of Hypoxia-inducible factors (HIF) in myeloid cells, leads to increased VEGF expression and most importantly, accelerated matrix degradation and reduced myofibroblast numbers after CCl4 challenge. This is associated with enhanced expression of MMP-2 and -14 as well as lower expression of TIMP-2 in liver endothelial cells. In addition, we report increased expression of MMP-13 in scar-associated macrophages as well as improved liver regeneration upon ablation of VHL in myeloid cells. Finally, therapeutic infusion of macrophages nulli-zygous for VHL or treated with the pharmacologic hydroxylase inhibitor and HIF-inducer Dimethyloxalylglycine (DMOG) accelerates resolution of fibrosis. Hence, boosting the HIF-VEGF signaling axis in macrophages represents a promising therapeutic avenue for the treatment of liver fibrosis.

Targeting VEGF-A in myeloid cells enhances natural killer cell responses to chemotherapy and ameliorates cachexia.

Chemotherapy remains a mainstay of cancer treatment but its use is often limited by the development of adverse reactions. Severe loss of body weight (cachexia) is a frequent cause of death in cancer patients and is exacerbated by chemotherapy. We show that genetic inactivation of vascular endothelial growth factor (VEGF)-A in myeloid cells prevents chemotherapy-induced cachexia by inhibiting skeletal muscle loss and the lipolysis of white adipose tissue. It also improves clearance of senescent tumour cells by natural killer cells and inhibits tumour regrowth after chemotherapy. The effects depend on the chemoattractant chemerin, which is released by the tumour endothelium in response to chemotherapy. The findings define chemerin as a critical mediator of the immune response, as well as an important inhibitor of cancer cachexia. Targeting myeloid cell-derived VEGF signalling should impede the lipolysis and weight loss that is frequently associated with chemotherapy, thereby substantially improving the therapeutic outcome.

Stakeholders' views on the ethical challenges of pragmatic trials investigating pharmaceutical drugs.

BACKGROUND: We explored the views of key stakeholders to identify the ethical challenges of pragmatic trials investigating pharmaceutical drugs. A secondary aim was to capture stakeholders' attitudes towards the implementation of pragmatic trials in the drug development process. METHODS: We conducted semistructured, in-depth interviews among individuals from different key stakeholder groups (academia and independent research institutions, the pharmaceutical industry, regulators, Health Technology Assessment (HTA) agencies and patients' organizations) through telephone or face-to-face sessions. Interviews were structured around the question "what challenges were experienced or perceived during the design, conduct and/or review of pragmatic trials." Respondents were additionally asked about their views on implementation of pragmatic trials in the drug development process. Thematic analysis was used to identify the ethically relevant features across data sets. RESULTS: We interviewed 34 stakeholders in 25 individual sessions and four group sessions. The four perceived challenges of ethical relevance were: (1) less controlled conditions creating safety concerns, (2) comparison with usual care potentially compromising clinical equipoise, (3) tailored or waivers of informed consent affecting patient autonomy, and (4) minimal interference with "real-world" practice reducing the knowledge value of trial results. CONCLUSIONS: We identified stakeholder concerns regarding risk assessment, use of suboptimal usual care as a comparator, tailoring of informed consent procedures and ensuring the social value of pragmatic trials. These concerns increased when respondents were asked about pragmatic trials conducted before market authorization.

Resolution of liver fibrosis requires myeloid cell-driven sinusoidal angiogenesis.

UNLABELLED: Angiogenesis is a key feature of liver fibrosis. Although sinusoidal remodeling is believed to contribute to fibrogenesis, the impact of sinusoidal angiogenesis on the resolution of liver fibrosis remains undefined. Myeloid cells, particularly macrophages, constantly infiltrate the fibrotic liver and can profoundly contribute to remodeling of liver sinusoids. We observe that the development of fibrosis is associated with decreased hepatic vascular endothelial growth factor (VEGF) expression as well as sinusoidal rarefication of the fibrotic scar. In contrast, the resolution of fibrosis is characterized by a rise in hepatic VEGF levels and revascularization of the fibrotic tissue. Genetic ablation of VEGF in myeloid cells or pharmacological inhibition of VEGF receptor 2 signaling prevents this angiogenic response and the resolution of liver fibrosis. We observe increased expression of matrix metalloproteases as well as decreased expression of tissue inhibitor of metalloproteases confined to sinusoidal endothelial cells in response to myeloid cell VEGF. Remarkably, reintroduction of myeloid cell-derived VEGF upon recovery restores collagenolytic acitivity and the resolution of fibrosis. CONCLUSION: We identify myeloid cell-derived VEGF as a critical regulator of extracellular matrix degradation by liver endothelial cells, thereby unmasking an unanticipated link between angiogenesis and the resolution of fibrosis.

Aberrant mural cell recruitment to lymphatic vessels and impaired lymphatic drainage in a murine model of pulmonary fibrosis.

Pulmonary fibrosis is a progressive disease with unknown etiology that is characterized by extensive remodeling of the lung parenchyma, ultimately resulting in respiratory failure. Lymphatic vessels have been implicated with the development of pulmonary fibrosis, but the role of the lymphatic vasculature in the pathogenesis of pulmonary fibrosis remains enigmatic. Here we show in a murine model of pulmonary fibrosis that lymphatic vessels exhibit ectopic mural coverage and that this occurs early during the disease. The abnormal lymphatic vascular patterning in fibrotic lungs was driven by expression of platelet-derived growth factor B (PDGF-B) in lymphatic endothelial cells and signaling through platelet-derived growth factor receptor (PDGFR)-ß in associated mural cells. Because of impaired lymphatic drainage, aberrant mural cell coverage fostered the accumulation of fibrogenic molecules and the attraction of fibroblasts to the perilymphatic space. Pharmacologic inhibition of the PDGF-B/PDGFR-ß signaling axis disrupted the association of mural cells and lymphatic vessels, improved lymphatic drainage of the lung, and prevented the attraction of fibroblasts to the perilymphatic space. Our results implicate aberrant mural cell recruitment to lymphatic vessels in the pathogenesis of pulmonary fibrosis and that the drainage capacity of pulmonary lymphatics is a critical mediator of fibroproliferative changes.