Atrium Therapeutics, Inc. · NASDAQ:RNA
Atrium Therapeutics — Investor Presentation (November 2026)
28 slides from Atrium Therapeutics's investor presentation, Nov 2, 2026
Slide 1: Atrium Therapeutics
Atrium Therapeutics 2 November 2026 RNA www.atriumtherapeutics.com LISTED NASDAQ 1
Slide 2: Forward-Looking Statements
Forward-Looking Statements Forward - Looking Statements FORWARD LOOKING STATEMENTS AND OTHER INFORMATION: Certain statements in this Presentation may constitute “forward - looking statem ents” for purposes of the federal securities laws. Our forward - looking statements include, but are not limited
Slide 3: Our vision: precision RNA medicines for the heart
Our vision: To pioneer precision RNA medicines for the heart and profoundly improve the lives of people impacted by cardiac diseases Our vision: To pioneer precision RNA medicines for the heart and profoundly improve the lives of people impacted by cardiac diseases 3
Slide 4: Atrium has made solid progress since our launch in February 2026
Atrium has made solid progress since our launch in February 2026 KEY MILESTONES • ATR 1072 cleared for trials in the U.S. and Canada • First patient dosed in Phase 1/2 clinical trial – Corventis PRKAG2 syndrome patient identification: 1 Build bottom- up view of full patient population ATR 1072 & ATR
Slide 5: Atrium is at the forefront of genetic cardiomyopathy treatment
Atrium is at the forefront of genetic cardiomyopathy treatment, and we're moving fast Patients and physicians are looking for more effective treatment options for genetic cardiomyopathies, and the market is primed for precision therapies Rare Cardiac Proven Ability Targeted Disease with High to Exec
Slide 6: A precision RNA platform primed for genetic cardiomyopathies
A precision RNA platform primed for genetic cardiomyopathies Monoclonal Oligonucleotide Antibody Oligonucleotide Antibodies Therapies Conjugate (AOC) OLIGO mAb mAb OLIGO Targeted Delivery Genetic Precision Scalable Platform ✓ RNA delivery technology designed ✓ Designed to directly target ✓ AOCs appl
Slide 7: Leadership team expertise in rare disease and RNA
Leadership team expertise in rare disease and RNA Leadership team expertise in rare disease and RNA Kath Gallagher | Chief Executive Officer and Board Member Rocio Martin | Chief Strategy Officer 20+ years in the biopharmaceutical industry leading portfolio strategy, 20+ years in various senior stra
Slide 8: Robust wholly-owned pipeline supported by strong capital position
Robust wholly - owned pipeline supported by strong capital position CLINICAL ANTICIPATED UPCOMING TARGET RESEARCH IND- ENABLING PHASE 1 PHASE 2 PHASE 3 MILESTONES Initial POC data PRKAG2 syndrome PRKAG2 ATR 1072 expected 2H 2027 IND filing PLN cardiomyopathy PLN ATR 1086 in 2027 Development Rare car
Slide 9: About Genetic Cardiomyopathies
About Genetic Cardiomyopathies 9
Slide 10: Millions of people with genetic cardiomyopathies lack disease-modifying treatments
Millions of people with genetic cardiomyopathies lack disease - modifying treatments Approximately 1% of patients with genetically driven cardiomyopathies are getting genetic testing1 ~2 Million diagnosed in the US 2 50% have underlying genetic Most managed through driver of disease 3,4 symptom cont
Slide 11: Three phenotypes across the genetic cardiomyopathy spectrum
Three phenotypes across the genetic cardiomyopathy spectrum Changes in cardiac structure and function can present independently and in combination Hypertrophic Dilated Arrhythmogenic Cardiomyopathy Cardiomyopathy Cardiomyopathy (HCM) (DCM) (ACM) Dyspnea, chest pain, Fatigue, exertional dyspnea, flui
Slide 12: ATR 1072 PRKAG2 Syndrome
ATR1072 PRKAG2 Syndrome ATRIUM
Slide 13: PRKAG2 syndrome
PRKAG2 s yndrome A rare, progressive disease that can lead to sudden cardiac death • Autosomal dominant disease caused by gene mutations in PRKAG2 that leads to AMPK overactivity resulting in 0 Approved glycogen accumulation in heart muscle therapies • Contributes to cardiomyopathy due to thickened
Slide 14: PRKAG2 syndrome prevalence likely exceeds our initial estimate
PRKAG2 s yndrome prevalence likely exceeds our initial estimate This work continues, building towards a confident view of the full population Patient identification strategy is Early findings to uncover the focused in three areas already diagnosed Uncover the already - diagnosed Our initial prevalen
Slide 15: ATR 1072 designed to silence mutant PRKAG2 to normalize AMPK activity
ATR 1072 designed to silence mutant PRKAG2 to normalize AMPK activity PRKAG2 is the regulatory Mutant PRKAG2 leads to Hypertrophic cardiomyopathy (HCM) characterized Mechanism component of AMPK overactivation of AMPK by glycogen accumulation and arrhythmia of Disease ATR 1072 - mediated degradation
Slide 16: Targeting PRKAG2 mRNA led to reversal of glycogen accumulation
Targeting PRKAG2 mRNA in the heart led to reversal of glycogen accumulation as well as improvement in other key features of the disease in nonclinical model 1 Cardiac glycogen accumulation reversed • Encouraging results in measures of 4 weeks after treatment hypertrophy include reduction in heart we
Slide 17: ATR 1072 improved cardiac hypertrophy in echocardiogram in nonclinical model
ATR 1072 improved measure of cardiac hypertrophy in echocardiogram in nonclinical model 1 Cardiac wall thickness decreased at 4 weeks after treatment Untreated diseased mice Treated diseased mice LVID LVID LVPW LVPW 1 mm LVID: Left ventricular internal diameter; LVPW: Left ventricular posterior wall
Slide 18: ATR 1072 has a favorable nonclinical safety profile and robust target knockdown
ATR 1072 has a favorable nonclinical safety profile and robust target knockdown 1 ATR 1072 activity in monkey heart following a single dose at 28 days of treatment ATR 1072 was generally well tolerated in 9 - month, repeat PRKAG2 mRNA dose chronic toxicity study in 150 cynomolgus monkey 125 Relative
Slide 19: ATR 1072: First trial targeting PRKAG2 syndrome ongoing
ATR 1072: First trial targeting PRKAG2 syndrome ongoing Initial trial data demonstrating proof of concept anticipated in 2H 2027 48 - week treatment PART A - Dose Escalation* PART B - Expansion Long - Term Extension Cohort A1 Cohort A2 Cohort A3 Cohort B All participants 40 mg 80 mg 160 mg Recommend
Slide 20: ATR 1086 PLN Cardiomyopathy
ATR 1086 PLN Cardiomyopathy 20
Slide 21: PLN Cardiomyopathy
PLN Cardiomyopathy A rare progressive disease with frequent family history • PLN - R14del is the most common disease - relevant PLN mutation 0 • Mutant PLN - R14del forms aggregates and impairs Approved cardiomyocyte function therapies • Characterized by dilated, arrhythmogenic or hypertrophic cardi
Slide 22: ATR 1086: Designed to silence mutant PLN
ATR 1086: Designed to silence mutant PLN to prevent protein aggregates and target root cause of disease 1 Phospholamban (PLN) regulates R14del mutation on PLN causes Dilated and Arrhythmogenic Mechanism Ca2+ handling in cardiomyocytes PLN to form protein aggregates cardiomyopathy (DCM & ACM) of Dise
Slide 23: ATR 1086 demonstrates functional improvement and survival in preclinical model
ATR 1086 demonstrates functional improvement and survival in preclinical model of disease 1 Reduction of human PLN expression Improved survival (Kaplan - Meier survival curve) and ejection in the heart following treatment with fraction following repeated ATR 1086 treatment (6 mg/kg) in a A TR 1086 (
Slide 24: Expansion Opportunities for ATR 1072 and ATR 1086
Expansion Opportunities for ATR 1072 and ATR 1086 A biology - driven pipeline with multiple indication expansion opportunities 24
Slide 25: Opportunities for indication expansion beyond a single genetically defined population
ATR 1072 and ATR 1086 have opportunities for indication expansion beyond a single genetically defined population Central Pathways in Opportunities for Cardiac Function Indication Expansion Energy sensing AMPK dysregulation is implicated PRKAG2 regulates AMPK across multiple genetic AMPK activity, th
Slide 26: Atrium is accelerating momentum post-launch with multiple milestones ahead
Atrium is accelerating momentum post - launch, with strong execution and multiple milestones ahead Achievements Anticipated Upcoming Milestones • GMP manufacturing • Initial proof- of- concept data by 2H 2027 • IND clearance and NOL ATR 1072 • First patient dosed in Corventis Ph 1/2 trial • Identifi
Slide 27: Expertise, leadership and focused pipeline to deliver in precision cardiology
Atrium has the expertise, leadership and focused pipeline to deliver in precision cardiology Platfor m Pipeline Execution Focused pipeline with Strong balance sheet with Proprietary RNA delivery indication expansion experienced leadership platform ideal for precision opportunities team cardiology 27
Slide 28: IR Contact
IR Contact Stephanie Kenney, Chief Corporate Affairs Officer investors@atrium - tx.com 28
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