Individualized 6‐mercaptopurine increments in consolidation treatment of childhood acute lymphoblastic leukemia: A NOPHO randomized controlled trial

Objectives

This randomized controlled trial tested the hypothesis that children with non‐high‐risk acute lymphoblastic leukemia could benefit from individualized 6‐mercaptopurine increments during consolidation therapy (NCT00816049). Primary and secondary end points were end of consolidation minimal residual disease (MRD) positivity and event‐free survival.

Methods

392 patients were randomized to experimental and 396 to standard therapy. Patients allocated to standard therapy received oral 6‐mercaptopurine (25 mg/m²/day) from days 30 to 85, while the experimental arm received stepwise increments of additional 25 mg/m²/day beginning on days 50 and/or 71 unless dose‐limiting myelosuppression had occurred.

Results

In the experimental arm, 166 patients (42%) received one dose increment, and 62 (16%) received two. Fifty‐seven of 387 (15%) patients in the experimental arm were MRD positive at end of consolidation vs 77 of 389 (20%) in the control arm (P = .08). Five‐year probability of event‐free survival was 0.89 (95% CI: 0.85‐0.93) in the experimental arm vs 0.93 (0.90‐0.96) in the control arm (P = .13). The median accumulated length of 6‐mercaptopurine treatment interruptions was 7 (IQR 2‐12) in the experimental arm vs 4 (IQR 0‐10) in the control arm (P = .002).

Conclusion

This study found no benefit from individualized 6‐mercaptopurine increments compared to standard therapy.     

Guide to designing, conducting, publishing and communicating results of clinical studies involving probiotic applications in human participants

The heterogeneity of human clinical trials to assess the effectiveness of probiotics presents challenges regarding interpretation and comparison. Evidence obtained from clinical trials among a population with a disease or specific risk factors may not be generalizable to healthy individuals. The evaluation of interventions in healthy persons requires careful selection of outcomes due to the absence of health indicators and the low incidence of preventable conditions. Given the tremendous resources invested in such trials, development of consistent approaches to assessing the effectiveness of probiotics would be beneficial. Furthermore, the reporting, presentation and communication of results may also affect the validity of the scientific evidence obtained from a trial. This review outlines the challenges associated with the design, implementation, data analysis and interpretation of clinical trials in humans involving probiotics. Best practices related to their design are offered along with recommendations for enhanced collaboration to advance research in this emerging field.     

Should We Reintroduce Previous Venous Thromboembolism Into Decision-Making for Anticoagulation in Atrial Fibrillation?

BackgroundWe aimed to investigate whether history of venous thromboembolism should be considered a prognostic factor for future thromboembolic events in patients with atrial fibrillation.MethodsThis was a nationwide cohort study of patients with incident atrial fibrillation from 2000-2017, defined and characterized using Danish health registries. Cox regression analyses were used to calculate hazard ratios and 95% confidence intervals for the outcomes ischemic stroke or systemic embolism, and ischemic stroke, systemic embolism, or venous thromboembolism, according to history of venous thromboembolism. Analyses were adjusted for components of the CHA₂DS₂-VASc score and time-varying use of oral anticoagulation.ResultsThe study included 246,313 patients with incident atrial fibrillation, of which 6,516 (2.6%) had previous venous thromboembolism. Patients with previous venous thromboembolism carried an overall similar adjusted risk of ischemic stroke or systemic embolism compared with patients without previous venous thromboembolism (reference; hazard ratio 0.99; 95% confidence interval, 0.90-1.09). When analyzing a composite thromboembolic outcome of ischemic stroke, systemic embolism, or venous thromboembolism, patients with previous venous thromboembolism were at high-risk (hazard ratio 1.76; 95% confidence interval, 1.64-1.90). Similar conclusions were drawn when stratifying by venous thromboembolism subtype, and when restricting to patients with low CHA₂DS₂-VASc scores or the non-anticoagulated subset of the study population.ConclusionPatients with atrial fibrillation and previous venous thromboembolism carried similar risk of ischemic stroke or systemic embolism compared with patients with atrial fibrillation without previous venous thromboembolism. Nonetheless, patients with previous venous thromboembolism remain a high-risk population due to an excess risk of future venous thromboembolism. Patients and physicians should keep this excess thromboembolic risk in mind when weighing the expected risks and benefits of oral anticoagulation in patients with atrial fibrillation.     

Risk of Recurrent Venous Thromboembolism: A Danish Nationwide Cohort Study

Purpose

In this study, we aimed to estimate recurrence risk after incident venous thromboembolism, stratified according to unprovoked, provoked, and cancer-related venous thromboembolism in a prospective cohort of inpatients and outpatients receiving routine care.