Effect of acoramidis on risk of death and heart problem-related hospitalizations in people with transthyretin amyloid cardiomyopathy: a plain language summary
BACKGROUND: Transthyretin amyloidosis with cardiomyopathy is a progressive, fatal disease characterized by deposition of extracellular misfolded transthyretin (TTR) in the myocardium. Eplontersen is an N-acetylgalactosamine ligand–conjugated antisense oligonucleotide targeting hepatocyte TTR messenger RNA to reduce the production of circulating TTR. METHODS: CARDIO-TTRansform is a Phase 3, randomized, double-blind, placebo-controlled trial to assess the efficacy and safety of eplontersen in transthyretin amyloidosis with cardiomyopathy. Key inclusion criteria include histological evidence of amyloid deposits or grade 2 to 3 cardiac uptake on cardiac scintigraphy in the absence of plasma cell dyscrasia, New York Heart Association class I–III, and end-diastolic interventricular septum thickness >12 millimeters. Participants were randomized 1:1 to receive eplontersen 45 mg or placebo, administered subcutaneously every 4 weeks for up to 140 weeks, followed by a 20-week post-treatment evaluation period or open-label extension. Participants received locally available standard of care, including unrestricted use of TTR stabilizers. The primary end point is a composite of cardiovascular mortality and recurrent clinical cardiovascular events through 140 weeks. Secondary end points, in order of testing hierarchy, include changes from baseline in 6-minute walk distance and Kansas City Cardiomyopathy Questionnaire overall summary score, recurrent cardiovascular events, all-cause mortality, the primary end point in the patient subgroup receiving stabilizers at baseline, and cardiovascular mortality. Echocardiography was performed in all participants, with cardiovascular magnetic resonance imaging and technetium scintigraphy in a subset. CONCLUSIONS: CARDIO-TTRansform is fully enrolled, with 1432 randomized participants who were dosed with study drug or placebo. As the largest transthyretin amyloidosis with cardiomyopathy study to date, it will evaluate whether eplontersen improves cardiovascular outcomes in patients receiving locally available standard of care, including TTR stabilizers. REGISTRATION: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT04136171. URL: http://ClinicalTrialsRegister.eu ; Unique identifier: EudraCT number 2019-002835-27.
Prognostic factors and progression biomarkers in AL amyloidosis: mapping current knowledge and critical gaps
Abstract The therapeutic landscape for systemic immunoglobulin light chain (AL) amyloidosis has been revolutionized by daratumumab-based regimens, achieving 76% 5-year overall survival in the landmark ANDROMEDA trial. However, the current prognostic models were developed using patient populations treated with now-suboptimal therapies, creating a critical gap between risk stratification models and contemporary outcomes. This comprehensive review analyzes prognostic factors and progression biomarkers in AL, categorizing them into disease-specific (clone-related and organ-related) and patient-specific factors. Notably, traditional baseline biomarkers including difference between involved and uninvolved free light chains and bone marrow plasma cell burden are losing prognostic significance with effective clone-directed therapies. Emerging approaches show promise, including dynamic markers such as minimal residual disease by free light chain mass spectrometry, cardiac imaging parameters such as global longitudinal strain, and functional measures. There is an urgent need for validation studies and prognostic model refinement to identify patients at high risk who may benefit from interventions beyond anti–plasma cell therapy.
A plain language review of the ATTRibute-CM study: efficacy and safety of acoramidis in transthyretin amyloid cardiomyopathy
BACKGROUND: In the phase 3 randomized controlled study ATTRibute-CM (Efficacy and Safety of AG10 in Subjects With Transthyretin Amyloid Cardiomyopathy), acoramidis, a transthyretin stabilizer, demonstrated significant efficacy on the primary end point. Participants with transthyretin amyloid cardiomyopathy who completed ATTRibute-CM were invited to enroll in an open-label extension study (OLE). We report the efficacy and safety data of acoramidis in participants who completed ATTRibute-CM and enrolled in the ongoing OLE. METHODS: Participants who previously received acoramidis through month 30 in ATTRibute-CM continued to receive it (continuous acoramidis), and those who received placebo through month 30 were switched to acoramidis (placebo to acoramidis). Participants who received concomitant tafamidis in ATTRibute-CM were required to discontinue it to be eligible to enroll in the OLE. Clinical efficacy outcomes analyzed through month 42 included time to event for all-cause mortality (ACM) or first cardiovascular-related hospitalization (CVH), ACM alone, first CVH alone, ACM or recurrent CVH, change from baseline in NT-proBNP (N-terminal pro-B-type natriuretic peptide), 6-minute walk distance, serum transthyretin, and Kansas City Cardiomyopathy Questionnaire Overall Summary score. Safety outcomes were analyzed through month 42. RESULTS: Overall, 438 of 632 participants in ATTRibute-CM completed treatment, and 389 enrolled in the ongoing OLE (263 continuous acoramidis and 126 placebo to acoramidis). The hazard ratio for ACM or first CVH was 0.57 (95% CI, 0.46–0.72) at month 42 based on a stratified Cox proportional hazards model ( P <0.0001) favoring continuous acoramidis. Similar analyses were performed on ACM alone and first CVH alone, with hazard ratios of 0.64 (95% CI, 0.47–0.88) and 0.53 (95% CI, 0.41–0.69), respectively, at month 42. Treatment effects for NT-proBNP and 6-minute walk distance also favored continuous acoramidis. On initiation of open-label acoramidis in the placebo-to-acoramidis arm, there was a prompt increase in serum transthyretin. Quality of life assessed by Kansas City Cardiomyopathy Questionnaire Overall Summary score was well preserved in continuous-acoramidis participants compared with the placebo-to-acoramidis participants. No new clinically important safety issues were identified in this long-term evaluation. CONCLUSIONS: Early initiation and continuous use of acoramidis in the ATTRibute-CM study through month 42 of the ongoing OLE study were associated with sustained clinical benefits in a contemporary transthyretin amyloid cardiomyopathy cohort, with no clinically important safety issues newly identified. REGISTRATION: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT04988386.
Abstract 4147141: Relationship Between CVH and Survival in the Acoramidis Treated Participants Within ATTRibute-CM
Background: Acoramidis is a novel, potent, investigational, transthyretin (TTR) stabilizer under development for the treatment of TTR amyloidosis that results in near-complete (≥90%) TTR stabilization. In a phase 3 study, ATTRibute-CM, acoramidis demonstrated improved clinical outcomes in participants with transthyretin amyloid cardiomyopathy (ATTR-CM), including a 50% reduction in the risk of CVH compared to placebo over 30 months. The study also demonstrated that cardiovascular hospitalization (CVH) during the study predicted a higher subsequent mortality in participants with ATTR-CM. Hypothesis: CVH portends a higher risk of mortality in participants with ATTR-CM. Since acoramidis reduces CVH, it can improve the prognosis of participants with ATTR-CM. Aim: To evaluate the relationship between CVH and survival in the acoramidis group within ATTRibute-CM. Methods: In this post-hoc analysis, the relationship between those with or without CVH and survival was analyzed within the acoramidis treatment group using the Kaplan-Meier (KM) estimator method. Results: Demographics and baseline disease characteristics were mostly comparable between acoramidis-treated participants with and without CVH, although participants with CVH had a higher baseline NT-proBNP and lower eGFR. At Month 30, in acoramidis-treated participants, those without any CVH (n=300) had a higher survival [86.8% (95% CI = 82.2, 90.3)] versus 62.4% (95% CI = 52.6, 70.7) in those who had any CVH (n=109); p<0.0001 from log-rank test (Figure). Conclusion: In the ATTRibute-CM study, pts without any CVH receiving acoramidis have a higher survival rate. CVHs remain a powerful predictor of mortality. This reinforces the importance of an effective therapy that reduces CVH and in turn may improve survival in patients with ATTR-CM.
The effect of long-term tafamidis treatment on quality of life in people with transthyretin amyloid cardiomyopathy (ATTR-CM): A plain language summary
Abstract Aims To evaluate the effect of long-term tafamidis treatment on health-related quality of life (HRQoL) in patients with transthyretin amyloid cardiomyopathy (ATTR-CM) enrolled in the Tafamidis in Transthyretin Cardiomyopathy Clinical Trial (ATTR-ACT) and long-term extension (LTE) study. Methods and results We examined change from baseline in Kansas City Cardiomyopathy Questionnaire overall summary (KCCQ-OS) and clinical summary (KCCQ-CS) scores in patients who received tafamidis meglumine 80 mg for 30 months in ATTR-ACT and tafamidis (meglumine 80 mg or bioequivalent free acid 61 mg) for 30 months in the LTE study, and in patients who received placebo for 30 months in ATTR-ACT and tafamidis for 30 months in the LTE study. In ATTR-ACT, 176 and 177 patients were randomized to tafamidis 80 mg and placebo, respectively. Patients who continuously received tafamidis had a 6- to 7-point reduction in least squares (LS) mean (standard error) KCCQ-OS and KCCQ-CS scores at month 30 (−6.25 [1.53] and −7.48 [1.39]), with little or no further decline over the next 30 months (−5.92 [1.77] and −9.21 [1.88] at month 60). Patients who received placebo in ATTR-ACT had a 20-point reduction in LS mean KCCQ-OS and KCCQ-CS scores at month 30 (−19.60 [1.94] and −19.90 [2.01]), but the decline slowed after initiating tafamidis (−24.70 [3.04] and −25.30 [3.36] at month 60). Conclusion Tafamidis reduced HRQoL decline in patients with ATTR-CM. Patients continuously treated with tafamidis for 60 months demonstrated stabilized HRQoL. In patients who initially received placebo in ATTR-ACT, tafamidis reduced the decline in HRQoL during the LTE study.
Efficacy and Safety of Acoramidis in Transthyretin Amyloid Cardiomyopathy