Attralus, Inc.

- Proceeds intended to advance clinical pipeline of transformational pan-amyloid removal (PAR) therapeutic candidates- Financing led by Alpha Wave Global and also included Bristol Myers Squibb (BMY) SAN FRANCISCO, Feb. 06, 2024 (GLOBE NEWSWIRE) -- Attralus, Inc., a clinical-stage biopharmaceutical company developing transformative medicines to improve the lives of patients with systemic amyloidosis, today announced that it has closed a $56 million financing. The financing round was led by new investor Alpha Wave Ventures and also included Bristol Myers Squibb (BMY). Existing investors also participated including founding investor venBio Partners, Surveyor Capital (a Citadel company), Vivo Capital, Logos Capital and Sarissa Capital Management. “This financing by a world-class syndicate of investors with deep expertise and experience in the life sciences space reflects the recognition of the strong potential of our pipeline of innovative pan-amyloid removal (PAR) therapeutic candidates to bring a new treatment approach to patients with systemic amyloidosis with potential to reverse the disease pathology,” said Mark Timney, CEO of Attralus. “With this support, we plan to accelerate our clinical development strategy to advance our portfolio programs.” Attralus intends to use the proceeds from the financing to advance the Phase 1/2 development of Attralus’ lead PAR therapeutic product, AT-02, in ATTR and AL amyloidosis. The financing proceeds are also expected to support the clinical development of the pan-amyloid diagnostic imaging agent I-124-Evuzamitide (AT-01) and AT-05 as well as the preclinical development of PAR therapeutic candidates for the treatment of neurodegenerative diseases. “We are thrilled to support Attralus in its vision to build a leading Systemic Amyloidosis company and the company’s approach of targeting removal of existing amyloid deposits, going beyond current treatments that slow progression but do not remove amyloid from organs” said Chris Dimitropoulos, Managing Director of Healthcare Investments at Alpha Wave Global. “We look forward to supporting Attralus as it progresses its programs and Attralus looks towards its next phase of growth.” About Systemic AmyloidosisSystemic amyloidosis encompasses a diverse group of rare diseases that occur due to accumulation of toxic amyloid deposits in tissues and organs, a consequence of aberrant protein misfolding events. These diseases are progressive, debilitating and often fatal. Systemic amyloidosis is significantly underdiagnosed due to low awareness, lack of specific symptoms, and no current disease-specific diagnostics. There are approximately 17 different types of systemic amyloidosis, which combined represent over 500,000 patients in the United States, the European Union and Japan. The two most common forms of systemic amyloidosis are transthyretin-associated amyloidosis (ATTR) and immunoglobulin light-chain-associated (AL) amyloidosis. While currently approved treatments slow disease progression by targeting precursor proteins, there is a significant unmet need for new therapies that can remove toxic amyloid deposits across all amyloid types and improve organ function and patient quality of life. About AT-02, Pan-Amyloid Removal TherapeuticAT-02 is the company’s lead pan-amyloid removal (PAR) therapeutic candidate for systemic amyloidosis. AT-02 is a humanized IgG1 monoclonal antibody genetically fused with the company’s proprietary pan-amyloid binding peptide, enabling binding to multiple types of amyloid deposits. The Fc region of the antibody stimulates the immune system to remove amyloid deposits that are bound by AT-02. AT-02 uses a similar pan-amyloid peptide to I-124-Evuzamitide, the company’s diagnostic agent, which has been shown in multiple clinical trials to selectively bind to amyloid deposits in the heart, liver, kidney, and other organs in multiple types of amyloidosis. As a result, the company expects AT-02 to bind specifically to amyloid in systemic amyloidosis patients. Preclinical data have shown the ability of AT-02 to bind to multiple amyloid types in major organs, induce macrophage mediated phagocytosis, and remove amyloid. AT-02 is currently being evaluated in an open label phase 1 / 2 clinical trial in ATTR and AL amyloidosis patients. About I-124-Evuzamitide, Pan-Amyloid Diagnostic (Also known as AT-01)I-124-Evuzamitide (iodine-124 Evuzamitide) utilizes the company’s pan-amyloid binding peptide as an amyloid-specific imaging agent to image all types of systemic amyloidosis by PET/CT imaging. In clinical trials, I-124-Evuzamitide has been shown to detect multiple types of amyloid deposits, including AL and ATTR, in major organs such as the heart, kidney, liver, and spleen. Attralus has a special protocol assessment (SPA) in place with the FDA to conduct a single pivotal Phase 3 trial for I-124-Evuzamitide. About AT-05, Pan-Amyloid DiagnosticAT-05, uses the same pan amyloid binding peptide as I-124 -Evuzamitide but is labelled with technetium-99m (Tc-99m, 99mTc). AT-05 is designed to be used with single-photon emission computerized tomography (SPECT) to be more accessible to community cardiologists, and thereby support broader screening in addition to diagnosis. AT-05 is currently in a Phase 1 clinical trial. About Neurodegeneration ProgramAttralus is developing the next generation of therapies for neurodegenerative diseases by simultaneously targeting multiple proteinopathies. Patients suffering from neurodegenerative diseases such as Alzheimer’s, Parkinson’s, and Lewy Body diseases, often have multiple proteinopathies. The company’s research is aiming to capitalize on this by binding to multiple misfolded protein aggregates including Aβ, Tau, and α-Synuclein. Attralus’ pan-amyloid product candidates provide an opportunity for therapeutics that can simultaneously target multiple proteinopathies in individual patients unlike approved therapies that target a single proteinopathy. The company is also exploring a blood brain barrier shuttle to potentially improve brain penetration. About AttralusAttralus is a clinical stage biopharmaceutical company focused on creating transformative medicines to improve the lives of patients with systemic amyloidosis. The company’s proprietary pan-amyloid removal (PAR) therapeutics are designed to directly bind to and remove toxic amyloid in organs and tissues. By targeting the disease-causing pathology in systemic amyloidosis diseases, PAR therapeutics have the potential to treat and reverse disease in patients with all types and stages of systemic amyloidosis. Attralus was founded by scientific experts in the field of amyloidosis and the company is headquartered in San Francisco. About Alpha Wave Alpha Wave is a global investment company with three main verticals: private equity, private credit, and public markets. It is led by Rick Gerson, Navroz Udwadia, and Ryan Khoury. Its flagship global private equity fund, Alpha Wave Ventures, aims to invest in best-in-class growth-stage companies and endeavors to be helpful long-term partners to the founders and management teams. Alpha Wave has offices in New York, Miami, London, Monaco, Madrid, Abu Dhabi, Tel Aviv, Bangalore, Jakarta, and Sydney. For more information, please visit www.alphawaveglobal.com. Forward-Looking StatementsThis press release contains forward-looking statements, including statements related to the efficacy, continued development, and potential of the Company’s product candidates. Words such as “developing,” “aiming,” “advance,” “will,” “potential,” “intends,” “expected,” “plan,” “shown” and similar expressions are intended to identify forward-looking statements. These forward-looking statements are based upon Attralus' current expectations. Forward-looking statements involve risks and uncertainties. Attralus' actual results and the timing of events could differ materially from those anticipated in such forward-looking statements as a result of these risks and uncertainties. Attralus expressly disclaims any obligation or undertaking to release publicly any updates or revisions to any forward-looking statements contained herein to reflect any change in Attralus' expectations with regard thereto or any change in events, conditions, or circumstances on which any such statements are based. Contact: Krishna Gorti, MD FRCSCorporate Development(212) 489-4351kgorti@attralus.com

124I-evuzamitide shown to be highly accurate for detection of cardiac amyloid across two independent investigator-initiated studies.124I-evuzamitide detects multiple types of systemic amyloidosis.124I-evuzamitide may be more sensitive than standard diagnostics, with cardiac uptake shown in ATTR patients who had negative 99mTc-PYP scans.Moderate-to-strong correlations were observed with 124I-evuzamitide uptake and structural and functional cardiac imaging measures, health related quality of life (HRQoL), and cardiac biomarkers. SAN FRANCISCO, Nov. 07, 2023 (GLOBE NEWSWIRE) -- Attralus, Inc., a clinical stage biopharmaceutical company developing transformative medicines to improve the lives of patients with systemic amyloidosis, today announced the publication of results from two Attralus-funded investigator-initiated studies of 124I-evuzamitide, the company’s investigational pan-amyloid radiotracer under development for the diagnosis and management of systemic amyloidosis. The manuscripts from Brigham and Women’s Hospital (BWH) and from the University of Tennessee Graduate School of Medicine were published in the Journal of American College of Cardiology – Cardiovascular Imaging (JACC CV Imaging). The manuscripts, entitled “Cardiac Amyloid Quantification Using 124I-Evuzamitide (124I-P5+14) Versus 18F-Florbetapir” and “Cardiac Amyloid Detection by PET/CT Imaging of Iodine (124I) Evuzamitide (124I-p5+14): A Phase 1/2 Study,” have been published online. These two manuscripts were also accompanied by an editorial entitled “Shining a Radiant Light on Cardiac Amyloidosis with Novel 124I-Evuzamitide PET Imaging.” All three articles can be found online here. The key data reported in the publications show PET/CT imaging of patients with diverse types of systemic amyloidosis with visually appreciable uptake in the heart with high sensitivity and other organs suspected of amyloid involvement and highlighted that 124I-evuzamitide imaging may detect cardiac amyloid prior to clinical manifestation. Furthermore, 124I-evuzamitide was shown to accurately discriminate amyloid cardiomyopathy (CMP) from controls. In patients with ATTRwt-CMP, performance may be better with 124I-evuzamitide, as evidenced by significantly higher uptake than 18F-florbetapir, and higher uptake than in AL patients aligning with literature that ATTR patients have a higher cardiac amyloid load. Moderate-to-strong correlations between 124I-evuzamitide uptake and cardiac structural and functional measures utilizing echocardiography and cardiac magnetic resonance imaging, health related quality of life (HRQoL) metrics, and cardiac biomarkers were observed. The results also support the potential of 124I-evuzamitide as a pan-amyloid imaging agent, with positive cardiac uptake also seen in AApoAIV, AApoA1 and ALys amyloidosis patients. Infusion of 124I-evuzamitide was generally safe and well tolerated in these studies. These studies suggest that 124I-evuzamitide is a promising novel radiotracer to detect and quantify cardiac amyloid in multiple types of amyloidosis. Furthermore, the authors from BWH study stated that the ability of 124I-evuzamitide to specifically bind to amyloid deposits is promising for the ongoing Phase I trial investigating a monoclonal antibody fusion protein incorporating a similar amyloid-binding peptide, which targets amyloid deposits to trigger their removal. “Cardiac amyloidosis is an underdiagnosed condition. Despite recent improvements, diagnosis continues to be a challenge. There is an unmet need for more sensitive and specific diagnostics” said Professor Sharmila Dorbala MD, MPH, Harvard Medical School, Cardiovascular Medicine, and lead author of the BWH study. “In our study, I-124 evuzamitide perfectly discriminated between healthy subjects and both AL and ATTR cardiac amyloidosis patients. In ATTR patients, myocardial uptake was significantly higher with I-124 evuzamitide than with F18-florbetapir, suggesting that diagnostic performance may be better with I-124 evuzamitide. Although not evaluated in this study, direct amyloid quantification with I-124 evuzamitide may be useful for diagnosis of early disease and for monitoring disease progression or response to treatment. We were particularly encouraged by the moderate to strong correlations between amyloid quantitation by I-124 evuzamitide and health-related quality of life metrics, cardiac biomarkers, and standard imaging measures of structure and function.” “Detection and quantification of amyloid burden in the heart is an unmet clinical need for patients with diverse types of systemic amyloidosis,” said Jonathan Wall, Ph.D., Distinguished Professor, University of Tennessee Graduate School of Medicine. “The iodine-124 evuzamitide radiotracer has the potential to be an invaluable tool to both detect early cardiac and extracardiac deposits and to quantify amyloid burden.” Summary of Published ResultsBWH studyThis pilot study enrolled 26 patients with systemic amyloidosis (12 AL, 12 ATTR and 2 other types) and 12 healthy volunteers (HVs). Eight additional HVs were included in the publication from a 18F-florbetapir study to compare the accuracy of 18F- florbetapir to 124I-evuzamitide. The BWH study is the first to systematically evaluate myocardial uptake of 124I-evuzamitide compared to standard imaging modalities, clinical metrics, and HRQoL parameters in a cohort of participants with amyloid CMP, and the first to compare it to 18F- florbetapir. The study evaluated the quantitative myocardial uptake of 124I-evuzamitide and measured correlations between 124I-evuzamitide and clinical markers of amyloid CMP. All patients received an IV infusion of 1 mCi of 124I-evuzamitide and images were acquired at 5 hours post injection. Quantitative uptake of 124I-evuzamitide perfectly discriminated all cases of known AL-CMP and ATTRwt-CMP from controls, using measures of left ventricular % injected dose (LV %ID), cardiac amyloid activity (CAA), and target to background ratio (TBR).When comparing radiotracers, 124I-evuzamitide consistently showed higher myocardial uptake in patients with ATTRwt amyloidosis, suggesting that it may perform better in these patients. The performance was similar to 18F- florbetapir in AL Amyloidosis.Furthermore, among AL and ATTRwt participants, 124I-evuzamitide LV %ID was moderately to strongly correlated with indirect metrics of amyloid burden, both structural and functional (interventricular septum thickness, LV mass index, MCF, GLS, ECV), assessed using standard echocardiographic and MRI techniques, suggesting valid amyloid burden quantitation.Cardiac uptake of 124I-evuzamitide strongly correlated with cardiac-related serum biomarkers (NT-proBNP and troponin), and moderately to strongly correlated with clinical and HRQoL measures, suggesting meaningfulness to patients. The results also include a case in which an ATTRwt patient showed positive cardiac uptake of 124I-evuzamitide, a negative 99mTc-PYP scan, with an amyloid positive cardiac biopsy, suggesting 124I-evuzamitide may be more sensitive than 99mTc-PYP.No cardiac uptake was observed in HVs. The results suggest that 124I-evuzamitide can accurately detect and quantify cardiac amyloid burden. With further validation, quantitative 124I-evuzamitide uptake may be particularly useful to diagnose early disease or to monitor disease progression or response to therapy in subjects with cardiac amyloidosis. UT studyThe first in human Phase 1/2 trial evaluated the ability of 124I-evuzamitide to detect amyloid deposits by PET/CT imaging in patients with diverse forms of systemic amyloidosis. The trial enrolled 50 systemic amyloidosis pts (23 AL, 20 ATTR and 7 other types) and 5 HVs. All patients received an IV infusion of <2 mg of 124I-evuzamitide (≤2 mCi of I-124) and images were acquired at ~5 hours post injection. Efficacy endpoints included patient- and organ-based sensitivity of 124I-evuzamitide uptake in the heart, liver, spleen, and kidney. Cardiac uptake of the radiotracer was observed in 100% of patients with ATTR in whom clinical evidence supported a diagnosis of amyloid CMP.Positive cardiac PET/CT imaging was observed in six patients with a diagnosis of ATTR amyloidosis but no clinical evidence of cardiac involvement, with negative 99mTc-PYP imaging and normal serum NTproBNP levels. At least one of these subjects had a confirmatory cardiac biopsy confirming ATTR amyloidosis in the heart.Of the major abdominothoracic organs, the sensitivity (positive percent agreement) between clinical findings and 124I-evuzamitide imaging was strongest for the heart (96.2%; 95% CI: 80.4-99.9; n=25/26). PET/CT imaging of 124I-evuzamitide in patients with ATTR and AL amyloidosis exhibited diverse anatomic uptake involving e.g., the lung, liver, kidney, pancreas, spheroid joints, spine, and abdominal fat, consistent with the systemic nature of these diseases, and with previously published autopsy findings. These data suggest that 124I-evuzamitide imaging can detect not only cardiac amyloidosis, but also extracardiac disease.No cardiac uptake was observed in HVs. The data from this first-in-human study supports the overall safety and efficacy of 124I-evuzamitide for detecting cardiac amyloidosis, as well as systemic amyloid deposits. About Systemic Amyloidosis Systemic amyloidosis encompasses a diverse group of rare diseases that occur due to accumulation of toxic amyloid deposits in tissues and organs, a consequence of aberrant protein misfolding events. These diseases are progressive, debilitating and often fatal. Systemic amyloidosis is significantly underdiagnosed due to low awareness, lack of specific symptoms, and no current disease-specific diagnostics. The two most common forms of systemic amyloidosis are immunoglobulin light-chain-associated (AL) amyloidosis and transthyretin-associated amyloidosis (ATTR). There is a significant unmet need for new therapies and diagnostics in systemic amyloidosis. About I-124-EVUZAMITIDE Pan-Amyloid Diagnostic (Also known as AT-01)I-124-EVUZAMITIDE (iodine-124 Evuzamitide) utilizes the company’s pan-amyloid binding peptide as an amyloid-specific imaging agent to image all types of systemic amyloidosis by PET/CT imaging. In initial clinical trials, I-124-EVUZAMITIDE has been shown to detect multiple types of amyloid deposits, including AL and ATTR, in major organs such as the heart, kidney, liver and spleen. Attralus obtained exclusive rights to commercialize I-124-EVUZAMITIDE under a commercial license agreement with the University of Tennessee Research Foundation. The same PAR-peptide technology is utilized in AT-02 and AT-04, two of the company’s therapeutic candidates. About Attralus Attralus is a clinical stage biopharmaceutical company focused on creating transformative medicines to improve the lives of patients with systemic amyloidosis. The company’s proprietary pan-amyloid removal (PAR) therapeutics are designed to directly bind to and remove toxic amyloid in organs and tissues. By targeting the universal disease-causing pathology in systemic amyloidosis diseases, PAR therapeutics have the potential to treat and reverse disease in patients with all types and stages of systemic amyloidosis. Attralus was founded by scientific experts in the field of amyloidosis and the company is headquartered in San Francisco. Forward-Looking Statements This press release contains forward-looking statements, including statements related to the efficacy, continued development, and potential of the Company’s product candidates. Words such as “novel,” “developing,” “first and only,” “potential,” “shown” and similar expressions are intended to identify forward-looking statements. These forward-looking statements are based upon Attralus' current expectations. Forward-looking statements involve risks and uncertainties. Attralus' actual results and the timing of events could differ materially from those anticipated in such forward-looking statements as a result of these risks and uncertainties. Attralus expressly disclaims any obligation or undertaking to release publicly any updates or revisions to any forward-looking statements contained herein to reflect any change in Attralus' expectations with regard thereto or any change in events, conditions, or circumstances on which any such statements are based. Contact:Krishna Gorti, MD FRCSCorporate Development‍(212) 489-4351kgorti@attralus.com

AT-01 is a first-in-class pan-amyloid imaging agent capable of detecting diverse types of systemic amyloidosis in multiple organs.AT-01 demonstrated to be highly accurate, with 100% sensitivity for detection of cardiac amyloid, across three independent investigator-initiated studies.Attralus-Sponsored Test-Retest repeatability study demonstrates excellent repeatability and supports the potential use of AT-01 imaging to monitor disease progression in patients with cardiac amyloidosis.AT-01 may be more sensitive than 99m-Tc pyrophosphate bone scintigraphy (Tc99-PYP) for detecting transthyretin cardiac amyloidosis in patients with hereditary ATTR-CA.AT-01 uptake in cardiac amyloidosis shows moderate and statistically significant correlations with traditional measures of cardiac structure and function.AT-01 has the potential to play a valuable role for diagnosing cardiac amyloidosis and for monitoring changes in organ-specific amyloid load. SAN FRANCISCO, Oct. 02, 2023 (GLOBE NEWSWIRE) -- Attralus, Inc., a clinical stage biopharmaceutical company developing transformative medicines to improve the lives of patients with systemic amyloidosis, announced eight data presentations (from an Attralus sponsored trial and from four investigator-initiated trials) related to the use of 124I-evuzamitide (AT-01), the company’s pan-amyloid binding imaging agent in development for the diagnosis and management of all types of systemic amyloidosis. These data were included in oral and poster presentations at the 28th Annual Scientific Session of the American Society of Nuclear Cardiology (ASNC) taking place September 29-October 1, 2023, in Toronto, Canada. “AT-01 has the potential to become an essential tool not only to streamline diagnosis, but also to provide a comprehensive assessment of disease burden and a means to monitor disease progression,” said Gregory Bell, M.D., Chief Medical Officer at Attralus. “We are impressed by the consistency of results across multiple studies and institutions. AT-01 has the potential to be the first and only non-invasive, pan-amyloid, whole body imaging diagnostic agent designed to detect all types of systemic amyloidosis across key organs.” “Diagnosis is a challenging and time-consuming process for systemic amyloidosis patients, with many going years without an accurate diagnosis, and losing critical time in the process,” said Ahmad Masri, M.D., Assistant Professor of Medicine and the Director of Cardiac Amyloidosis and Hypertrophic Cardiomyopathy Centers at Oregon Healthy & Science University. “In our study, we were able to learn important disease characteristics about our patients that we cannot learn from any currently available imaging agent. The AT-01 data we generated provide an impressive road map to detecting and quantifying amyloid deposits in multiple organs across different types of amyloidosis, with the potential to detect amyloid earlier in the disease process and the ability to monitor organ specific disease progression or response.” “Despite recent progress in diagnosis, ATTR patients continue to go undiagnosed or are diagnosed late in their disease. A delayed diagnosis leads directly to poorer outcomes for patients. Bone Scintigraphy with Tc99-PYP imaging is the current standard for a non-biopsy diagnosis for cardiac ATTR, but in the seminal study, its utility was only ‘70% sensitive’,” said Mat Maurer, M.D., Arnold and Arlene Goldstein Professor of Cardiology at Columbia University Irving Medical Center. “In our study, we were able to demonstrate cardiac uptake with AT-01 in hereditary ATTR patients who were negative with the standard imaging, Tc99-PYP, for non-biopsy diagnosis of cardiac ATTR, implying that I124 Evuzamitide is a more sensitive diagnostic. The data from AT-01 are encouraging as an imaging agent that could directly detect amyloid deposits and diagnose patients earlier in their disease. This could be invaluable for patients and would be a welcome addition to our practice for more prompt and accurate diagnosis.” Oral Presentation Details Abstract Title: 124I-evuzamitide PET/MR Unveils Hypertrophic Cardiomyopathy in a Patient with Renal AL Amyloidosis Presented by: Jessica Cardin, Ph.D. and Ahmad Masri, M.D., Assistant Professor of Medicine, Division of Cardiovascular Medicine, Knight Cardiovascular Institute at OHSU Oregon Health & Science UniversityDate/Time: September 30, 2023, 9:55 a.m. – 9:59 a.m. EDTSession: 204 – Rapid-Fire Cases: Amyloidosis and Technology, Tracers, Instrumentation, SoftwareHighlights: AT-01 PET/MR case report Abstract Title: I-124 Evuzamitide PET/CT is More Sensitive than Tc-99m Pyrophosphate for the Diagnosis of Hereditary Transthyretin Cardiac Amyloidosis Presented by: Dia A. Smiley, D.O. and Mathew S. Maurer, M.D., Arnold and Arlene Goldstein Professor of Cardiology at Columbia University Irving Medical CenterDate/Time: October 1, 2023, 8:00 a.m. EDTSession: 301 – Controversies in Cardiac AmyloidosisHighlights: Ten hereditary ATTR patients with negative Tc99-PYP scans were included in the analysis.All subjects with known cardiac amyloidosis had positive AT-01 uptake.Cardiac Uptake of AT-01 was observed in eight out of ten hereditary ATTR patients who had a negative Tc99-PYP scan, the current standard for non-biopsy diagnosis of cardiac ATTR, suggesting AT-01 is more sensitive than Tc99-PYP for detection of cardiac amyloid. Of these eight, five patients were confirmed positive via a cardiac biopsy and three were diagnosed through other imaging and genetic testing. Poster Presentation DetailsPoster 216-04: Iodine-124-Evuzamitide PET/CT in Systemic Amyloidosis: Safety Evaluation & Reproducibility of Cardiac Uptake Quantitation Presented by: Gregory Bell, M.D., Attralus, Inc.Date/Time: September 30, 2023, 3:15 p.m. - 4:15 p.m. EDTHighlights: 33 systemic amyloidosis patients were enrolled and received ≥1 dose of AT-01, and 27 received two doses of AT-01 (image-evaluable population).There were no TEAEs related to AT-01 administration, and no TEAEs occurred on the day of dosing.Semiquantitative assessments of AT-01 cardiac uptake demonstrated high levels of intra- and inter-rater consistency.Interclass Coefficient Correlation (ICC) values in the heart were >0.95; Cardiac repeatability coefficients using SUV peak are consistent with other PET/CT tracers.These findings support the potential use of this novel imaging agent to monitor disease progression in patients with cardiac amyloidosis. Poster 216-13: First-in-Human Cardiac and Whole-Body 124I-evuzamitide (AT-01) PET/MRI in Systemic Amyloidosis Presented by: Ahmad Masri, M.D., Assistant Professor of Medicine, Division of Cardiovascular Medicine, Knight Cardiovascular Institute at OHSU Oregon Health & Science UniversityDate/Time: September 30, 2023, 3:15 p.m. – 4:15 p.m. EDTHighlights: 50 subjects were enrolled in this study, including 36 cardiac amyloidosis patients and 14 controls. Controls included patients with high LVH, HCM and systemic amyloidosis patients without cardiac amyloid. Cardiac amyloidosis was ruled out in control population.In this population of patients diagnosed with or suspected to have cardiac amyloidosis, AT-01 PET/MRI had a 100% sensitivity and specificity for the diagnosis of cardiac amyloidosis.Mean myocardial to LV blood pool SUV ≥1.45 yielded a 100% sensitivity and specificity for the diagnosis of cardiac amyloidosis.AT-01 PET/MRI is feasible and provides comprehensive diagnostic evaluation and organ survey of patients suspected to have or diagnosed with systemic amyloidosis. Poster 216-14. Relationship Between Myocardial 124I-evuzamitide Uptake and Cardiac Structure and Function: A Cardiac PET/MRI Study Presented by: Ahmad Masri, M.D., Assistant Professor of Medicine, Division of Cardiovascular Medicine, Knight Cardiovascular Institute at OHSU Oregon Health & Science UniversityDate/Time: September 30, 2023, 3:15 p.m. – 4:15 p.m. EDTHighlights: 50 subjects were enrolled in this study, including 36 cardiac amyloidosis patients and 14 controls.AT-01 was safe without any serious adverse events and no tracer-related adverse events.There were moderate and significant correlations of AT-01 uptake with measures of cardiac structure and function on CMR.In this high-risk group of suspected cardiac amyloidosis, an ECV cut-off of 39% yielded a higher diagnostic performance than a cut-off of 30%.ECV and AT-01 mean myocardial SUVR had a moderate and statistically significant correlation coefficient of 0.6.AT-01 cardiac PET/MRI provides comprehensive diagnostic evaluation of cardiac structure, function, and surrogates for amyloid load. Poster 216-16. Quantitative Assessment of Changes in Cardiac and Extracardiac Amyloid Load in Patients with AL and ATTR Amyloidosis, Measured By PET/CT Imaging Using the Pan-Amyloid Reactive Radiotracer Iodine (124I) Evuzamitide Presented by: Alan Stuckey, C.N.M.T., University of Tennessee Graduate School of MedicineDate/Time: September 30, 2023, 3:15 p.m. – 4:15 p.m. EDTHighlights: The study has enrolled 19 patients (AL (n=9) and ATTR (n=10)) who had positive cardiac uptake of AT-01 in a previous phase 1 for the purpose of evaluating longitudinal change in uptake over time.The mean time between imaging sessions was 3.0±0.9 years.In patients with ATTR amyloidosis (n=10) on silencers or stabilizer therapy, cardiac amyloid assessed by AT-01 uptake changed by -2.4%±21.4% (range –24.7% to +49.5%). Despite therapy, only 1 out of 10 cardiac ATTR patients had a decrease of ≥25% after a mean of 3 years.In patients with AL (n=9) who were in hematologic remission, cardiac amyloid changed by 1.5%±37.6% (range -24.7% to +92.7%). Despite being in heme remission, only 1 out of 10 cardiac AL patients had a decrease of ≥25%.In contrast, in AL patients the liver and splenic decreased dramatically, -25.5%±25.3% and -16.6%±49.9%, respectively.Significant correlations were observed between echocardiography parameters, serum NTproBNP and cardiac SUVR mean measurements.Changes in cardiac amyloid load, based on differential uptake of radiotracer, can be quantified using AT-01 PET/CT imaging and may be useful for monitoring changes in organ-specific amyloid load. Poster 216-23. Comparing Novel Quantitative 124I-Evuzamitide PET/CT Metrics to Diagnose Cardiac Amyloidosis Presented by: Olivier F. Clerc, M.D., MPH, Researcher, Brigham and Women's HospitalDate/Time: September 30, 2023, 3:15 p.m. – 4:15 p.m. EDTHighlights: This study included 43 participants: 12 with light-chain (AL) cardiomyopathy (CMP),12 with wild-type transthyretin (ATTRwt) CMP and 20 controls.CMP participants underwent PET/CT with both radiotracers AT-01 and 18F-florbetapir.In CMP participants, median age was 74 years (IQR 69 – 78) and 92% were male.Median AT-01 left ventricular percentage of injected dose (LV %ID) was 0.17 (IQR 0.07 – 0.45) in AL-CMP, 0.44 (0.35 – 0.75) in ATTRwt-CMP, and 0.00 (0.00 – 0.01) in controls (p<0.001).High LV %ID perfectly discriminated CMP from controls.In ATTRwt-CMP, LV %ID was higher with AT-01 (p=0.002) than with 18F-florbetapir.AT-01 LV %ID had intermediate to strong correlations with interventricular septal thickness (ρ=0.80) and LV strain (ρ=0.55) on echocardiography, as well as with LV mass index (ρ=0.82) and extracellular volume (ρ=0.55, all p≤0.02) on MRI.AT-01 detects amyloid CMP and accurately discriminates it from controls, with higher uptake than 18F-florbetapir in ATTRwt-CMP.Correlations with cardiac structural and functional metrics imply valid amyloid quantification. Poster 216-25 - I-124 Evuzamitide PET/CT is More Sensitive than Tc-99m Pyrophosphate for the Diagnosis of Hereditary Transthyretin Cardiac Amyloidosis Presented by: Dia A. Smiley, D.O. and Mathew S. Maurer, M.D., Arnold and Arlene Goldstein Professor of Cardiology at Columbia University Irving Medical CenterDate/Time: September 30, 2023, 3:15 p.m. - 4:15 p.m. EDTHighlights: Same findings as oral presentation in Session 301 - Controversies in Cardiac Amyloidosis. For additional information, please visit the ASNC 2023 https://www.asnc.org/asnc2023. About 124I-evuzamitide (AT-01) Pan-Amyloid Diagnostic124I-evuzamitide (AT-01) utilizes the company’s pan-amyloid binding peptide as an amyloid-specific imaging agent to image all types of systemic amyloidosis by PET/CT imaging. In initial clinical trials, AT-01 has been shown to detect multiple types of amyloid deposits, including AL and ATTR, in major organs such as the heart, kidney, liver and spleen. Attralus obtained exclusive rights to commercialize AT-01 under a commercial license agreement with the University of Tennessee Research Foundation. Similar PAR-peptide technology is utilized in AT-02 and AT-04, two of the company’s therapeutic candidates. About Systemic Amyloidosis Systemic amyloidosis encompasses a diverse group of rare diseases that occur due to accumulation of toxic amyloid deposits in tissues and organs, a consequence of aberrant protein misfolding events. Amyloid Light Chain (AL) is caused by a bone marrow disorder in which the light chain proteins become misfolded and accumulate as amyloid fibrils, in the heart, kidneys, liver, nerves and other organs. AL is progressive, debilitating, and often fatal. There is a significant unmet need for new therapies and diagnostics in systemic amyloidosis, especially AL. About Attralus Attralus is a clinical stage biopharmaceutical company focused on creating transformative medicines to improve the lives of patients with systemic amyloidosis. The company’s proprietary pan-amyloid removal (PAR) therapeutics are designed to directly bind to and remove toxic amyloid in organs and tissues. By targeting the universal disease-causing pathology in systemic amyloidosis diseases, PAR therapeutics have the potential to treat and reverse disease in patients with all types and stages of systemic amyloidosis. Attralus was founded by scientific experts in the field of amyloidosis and the company is headquartered in San Francisco. Forward-Looking Statements This press release contains forward-looking statements, including statements related to the efficacy, continued development, and potential of AT-01. Words such as “developing,” “potential,” “shown” and similar expressions are intended to identify forward-looking statements. These forward-looking statements are based upon Attralus’ current expectations. Forward-looking statements involve risks and uncertainties. Attralus’ actual results and the timing of events could differ materially from those anticipated in such forward-looking statements as a result of these risks and uncertainties. Attralus expressly disclaims any obligation or undertaking to release publicly any updates or revisions to any forward-looking statements contained herein to reflect any change in Attralus’ expectations with regard thereto or any change in events, conditions, or circumstances on which any such statements are based. Contact:Krishna Gorti, M.D. FRCSCorporate Developmentkgorti@attralus.com