Open heart
Stage-dependent timing of relative and absolute treatment benefit in transthyretin amyloid cardiomyopathy
By Nabeshima Y, Kaneko T, Yajima A and 2 others.
Abstract
Background
In transthyretin amyloid cardiomyopathy (ATTR-CM), treatment effects are often delayed and stage-dependent, which complicates interpretation of a single HR. The timing of relative and absolute benefit at each stage is unclear. We examined stage-specific treatment effects of tafamidis using complementary time-to-event analyses.
Methods
Individual patient-level data were reconstructed from published Kaplan-Meier curves of the Tafamidis in Transthyretin Cardiomyopathy Clinical Trial long-term extension and analysed by National Amyloidosis Centre (NAC) stage. Time to benefit (TTB) was estimated from flexible parametric (Royston-Parmar) models with time-varying treatment effects, providing time-varying HRs and absolute risk reduction and was cross-checked with truncated Cox and restricted mean survival time (RMST) trajectory analyses.