Safety and Efficacy of SGLT2 Inhibitors for Amyloid Light-Chain Cardiomyopathy

Abstract

BackgroundSodium-glucose cotransporter-2 inhibitors (SGLT2i) have demonstrated benefit in patients with heart failure, but minimal data exists around the use of these medications in amyloid light-chain cardiomyopathy (AL-CM). We performed a retrospective study assessing the safety and efficacy of SGLT2i in AL-CM. MethodsWe queried our institutional registry and identified 27 AL-CM patients who received SGLT2i. The safety analysis included all 27 patients and assessed SGLT2i-associated adverse events, hospitalizations, and deaths. To decrease confounding, the efficacy analysis included only a subset of patients with stable disease (on stable anti-plasma cell therapy for ≥2 months prior to baseline and achieved at least a hematologic Very Good Partial Response) and compared disease marker changes in these patients (n=17) with those of a contemporaneous untreated control cohort from our registry (n=21). ResultsThe mean age of the overall population was 68.6 (standard deviation 9.4) years. Seven (14.6%) patients had diabetes, and 19 (39.6%) had chronic kidney disease. In the safety analysis, median follow-up time was 10.9 (interquartile range 7.2) months. Two (7.4%) patients discontinued SGLT2i due to hypovolemia and genital irritation, and 6 (22.2%) additional patients temporarily held SGLT2i due to an adverse event, commonly related to volume depletion. Thirteen hospitalizations, all considered unrelated to SGLT2i use, and no deaths occurred. In the efficacy analysis, SGLT2i-treated patients had more severe disease at baseline than controls, demonstrating significantly higher median troponin-T and loop diuretic dose (P<0.05). Compared with controls, SGLT2i treatment was associated with significantly greater reductions in loop diuretic dose (P<0.001) and NTproBNP (P=0.033) across 3-, 6-, and 12-month follow-up timepoints. SGLT2i treatment was also associated with a significantly greater reduction in mean arterial pressure at 12 months (P=0.031) but not at other timepoints. No significant differences were observed on changes in weight, eGFR, troponin-T, proteinuria, or albumin. ConclusionsIn this small-scale retrospective study, we demonstrate that SGLT2i is well-tolerated by most patients with AL-CM, but volume depletion symptoms may limit continuous use. SGLT2i may aid management of congestion in AL-CM as evidenced by reduced diuretic dose and NTproBNP without adverse renal effects. Larger long-term studies are needed to build on our findings.