Cardiac amyloidosis patients already face a compounding burden: the same misfolded transthyretin protein that infiltrates heart muscle also damages kidneys, yet until now the renal consequences of treating this disease have been poorly mapped. A clearer picture emerges from pooled phase 2 and phase 3 trial data, and it carries meaningful implications for how clinicians weigh therapeutic trade-offs in this population.
Acoramidis, a small-molecule transthyretin stabilizer achieving at least 90% stabilization, was tested across 681 participants with transthyretin amyloid cardiomyopathy. Shortly after initiation, eGFR dropped a mean of 8.5 mL/min per 1.73 m² by day 28 — a hemodynamically mediated dip that was dose-dependent and fully reversible, without accompanying adverse kidney events. More consequentially, the chronic eGFR slope in the acoramidis group declined at −1.01 mL/min/1.73 m²/year versus −3.48 in the placebo arm — a 71% relative attenuation of kidney function loss. Urinary albumin-to-creatinine ratio was simultaneously reduced by roughly 14–16%, and this benefit was sustained longitudinally, suggesting reduced glomerular stress rather than a transient artifact.
This finding situates acoramidis in an interesting position relative to tafamidis, the earlier-approved stabilizer in the same class. Concomitant tafamidis use did not alter the chronic eGFR slope in either arm, implying these renal gains are specific to acoramidis's higher stabilization efficacy rather than a class effect. That distinction matters because cardiorenal syndrome — where cardiac dysfunction accelerates kidney deterioration — is a well-documented driver of morbidity in heart failure broadly, and amyloid cardiomyopathy is no exception. The mechanistic pathway likely involves improved cardiac output reducing renal hypoperfusion, but the albuminuria reduction hints at possible direct tubular or glomerular protection as well. As an observational-within-trial analysis, causality is inferred rather than directly proven, and longer follow-up in real-world cohorts will be needed to confirm durability. Still, the magnitude and consistency across two independent studies make this more than incremental — it reframes acoramidis as potentially protective for the cardiorenal axis, not merely the heart.