A Platform Trial for Gram Negative Bloodstream Infections

BALANCE+ is an adaptive platform trial evaluating multiple treatment options in patients admitted to the hospital due to Gram negative bloodstream infections (BSIs). It focuses on both cross-cutting and subgroup-specific questions, using an open-label, pragmatic design embedded in routine care. BALANCE+ addresses the significant health concern of BSIs, which have high morbidity and mortality rates, exacerbated by the global public health threat of antimicrobial resistance (AMR). With rising resistance rates and limited new drug development, effective treatment strategies for BSIs remain under-researched. BALANCE+ follows the BALANCE trial, which evaluated duration of antibiotic treatment, and aims to further investigate critical questions in managing Gram-negative BSIs. This platform trial will explore various aspects of BSI treatment, including antibiotic de-escalation, oral antibiotic choices, central line management, treatment of specific pathogens, and the necessity of follow-up blood cultures. BALANCE+ is using Bayesian methods without a fixed sample size. Interim analyses will occur after every 1000th patient in each domain, and then for every 200th patient thereafter. The trial will stop if futility or superiority thresholds are met, or if a domain reaches its ceiling sample size (2500 patients for most domains and 4000 for the beta-lactam versus non-beta-lactam domain) without meeting a stopping threshold. A vanguard pilot trial involving over 150 patients at 9 hospitals across Canada confirmed the feasibility of the BALANCE+ trial. The main trial will include patients from the vanguard pilot phase since there has been no major change in the overall study design and domains. The adaptive design allows for interim analyses and adjustments by adding or removing domains as per the statistical analysis plan, enhancing the trial's efficiency and relevance.