SPC365

ATTR-CM Under the Microscope: Comparing Real-World with Trial Outcomes

Session: SESSÃO DE POSTERS 06 - AMILOIDOSE CARDÍACA
Speaker: Catarina Gregório

Congress: CPC 2025
Topic: F. Valvular, Myocardial, Pericardial, Pulmonary, Congenital Heart Disease
Theme: 17. Myocardial Disease
Subtheme: 17.4 Myocardial Disease – Treatment
Session Type: Cartazes
FP Number: ---
Authors: Catarina Gregório; Miguel Raposo; Ana Beatriz Garcia; Marta Vilela; João Cravo; Daniel Cazeiro; Catarina Campos; Isabel Conceição; Fausto J. Pinto; Dulce Brito; João R. Agostinho

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Calibri,sans-serif"><span style="color:#000000"><strong>Introduction</strong></span></span></span><span style="font-size:11pt"><span style="font-family:Calibri,sans-serif"><span style="color:#000000">: Transthyretin amyloid cardiomyopathy (ATTR-CM) is a progressive and life-threatening disease that leads to heart failure and increased mortality. Pivotal clinical trials - ATTR-ACT, HELIOS-B, and ATTRibute-CM - have provided robust evidence supporting the efficacy of TTR stabilizers or synthesis inhibitors in reducing mortality and cardiovascular events.&nbsp;&nbsp;</span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Calibri,sans-serif"><span style="color:#000000"><strong>Aim</strong></span></span></span><span style="font-size:11pt"><span style="font-family:Calibri,sans-serif"><span style="color:#000000">: To compare the cardiovascular outcomes of a real-World cohort of patients with ATTR-CM under tafamidis treatment with those reported in the ATTR-CM pivotal trials.</span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Calibri,sans-serif"><span style="color:#000000"><strong>Methods</strong></span></span></span><span style="font-size:11pt"><span style="font-family:Calibri,sans-serif"><span style="color:#000000">: Single-center, perspective, single-arm observational study of consecutive patients with ATTR-CM treated with tafamidis 61mg. Their clinical, laboratorial and echocardiographic characteristics were collected and compared with data from the three studies using Student&#39;s T Test. The endpoint of all-cause mortality at 24 months was assessed using the Kaplan-Meier survival curve.</span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Calibri,sans-serif"><span style="color:#000000"><strong>Results</strong></span></span></span><span style="font-size:11pt"><span style="font-family:Calibri,sans-serif"><span style="color:#000000">: 89 patients were included (76 males, 39 with hereditary ATTR and 37 with wild-type ATTR). The real-World population was older (mean age 78.6 &plusmn; 10.7 years, p&lt;0.001) and had better functional capacity (p&lt;0.001) when compared to the ATTR-ACT study population. However, it appeared to have a slightly worse functional capacity when compared to the ATTRibute-CM population (p&lt;0.001). This real-World cohort is composed of a significantly higher rate of patients with hereditary ATTR (p&lt;0.001), which may be explained by the endemicity of p.Val50Met mutation in Portugal.</span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Calibri,sans-serif"><span style="color:#000000">The KCCQ-OS score at follow-up was worse in the real-World population compared to the ATTR-ACT (p&lt;0.001), HELIOS-B (p&lt;0.001) and ATTRibute-CM studies (p&lt;0.001) populations. There were no statistically significant differences in NT-proBNP levels between groups (p=NS). During a follow-up of 27.4&plusmn;2.1 months, there were 7 hospitalizations for heart failure in the real-World population, 5 patients died, 3 due to cardiovascular causes. </span></span></span><span style="font-size:11pt"><span style="font-family:Calibri,sans-serif"><span style="color:#000000"><span style="background-color:#ffffff">The all-cause mortality rate at 27 months was 26% in ATTR-CM, 18% in ATTRibute-CM and 12% in HELIOS-B, while in this real-World cohort it was 5.6%.</span></span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Calibri,sans-serif"><span style="color:#000000"><span style="background-color:#ffffff"><strong>Conclusions: </strong></span></span></span></span><span style="font-size:11pt"><span style="font-family:Calibri,sans-serif"><span style="color:#000000"><span style="background-color:#ffffff">This study data shows that patients selected for ATTR-CM disease modifying therapy in the real-World present clinical characteristics similar to those included in the pivotal trials. This suggests that patient selection has followed the trials&rsquo; inclusion criteria. Despite having worse quality of life - which does not seem to be explained by disease severity - this real-World population had better survival when compared to the trials&rsquo; populations.</span></span></span></span></p>