Aficamten

Today, BioPharma Dive is highlighting some notable clinical trial updates presented at the annual meeting of the European Society of Cardiology. Over the weekend, several large pharmaceutical and biotechnology companies released detailed study data on medicines for an array of different heart conditions.Below are three notable datasets and a look at how theyre being interpreted by investors and analysts.Cytokinetics stock sell-offCytokinetics claimed one of the bigger clinical trial victories in biotech this year when, in June, it disclosed that its drug Myqorzo succeeded in a Phase 3 trial in people with the non-obstructive form of the heart condition hypertrophic cardiomyopathy. That study made Myqorzo the first drug of its kind to prove beneficial against both forms of the condition, and separated it from Bristol Myers Squibbs market leading medicine Camzyos.On Friday, detailed data from that study were published in The New England Journal of Medicine and presented at ESC. Multiple Wall Street analysts claimed those findings reinforced Myqorzos potential despite the disclosure of a possible safety concern that sank Cytokinetics stock price.According to the NEJM paper, patients randomized to receive Myqorzo had an average 11.4-point improvement on a questionnaire assessing heart health after 36 weeks, compared to an 8.4-point change for placebo recipients. Peak oxygen consumption also improved for those treated with Myqorzo and slightly declined for those in the placebo group.Overall, Myqorzos effects were consistent across all study groups analyzed, reiterating Cytokinetics initial results, wrote Leerink Partners analyst Roanna Ruiz. And, importantly, the drugs impact on assessment scores appeared to grow over time, added Stifels James Condulis.The efficacy data are robust, Condulis wrote in his own note.Still, Cytokinetics shares fell more than 7% on Friday, as the paper also revealed 10 patients receiving Myqorzo experienced a specific kind of heart failure, versus three patients on placebo. That disclosure will likely add to an already lingering debate about the safety of Myqorzo and other drugs like it for people with non-obstructive disease, according to Condulis. (About one-third of patients have this form of HCM, which doesnt impede blood flow to the heart but can still put people at risk of poor health outcomes.)Yet Condulis and others argued the overall evidence should still support a new approval for Myqorzo and lead to broader uptake. Mizuho Securities analyst Salim Syed, for example, noted how there were no deaths among Myqorzo-treated patients, compared to three in the placebo arm. And patients with that form of the condition have essentially zero options currently.The stock sell-off is like missing [the] forest for trees, Syed added.Arrowheads edgeArrowhead Pharmaceuticals and Ionis Pharmaceuticals are already dueling for market supremacy in a rare disease that leads to extremely high triglycerides. That battle is soon to extend to a more common condition, with potentially billions of dollars at stake and where some analysts believe Arrowhead might have an advantage.Arrowhead in July said its drug plozasiran met the objectives of two late-stage studies in adults with severe hypertriglyceridemia, or sHTG. Those findings positioned Arrowhead to expand plozasirans use and directly challenge Ionis, which nabbed an approval in sHTG for its drug Tryngolza in June.At ESC, Arrowhead provided fuller details from those two studies and, to multiple analysts, described a drug with comparable efficacy to Tryngolza but potentially better safety. Prakhar Agrawal, of Cantor Fitzgerald, argued that plozasiran appears safer across several metrics, among them side effects leading to study discontinuations and liver enzyme or fat increases the latter of which has been a key focus for investors.The two drugs havent been tested against one another. But among patients who underwent a specialized imaging test in Arrowheads trials, plozasiran recipients had a roughly 1.5% placebo-adjusted increase in liver fat, compared to a 2% or 4% increase for Tryngolza recipients in Ionis studies, Agrawal noted.While specialists Agrawal spoke with suggested the liver fat increases Ionis reported may not be clinically meaningful, his team nonetheless expects it to be a factor in Arrowheads drug becoming the preferred option.Plozasirans results arguably support a best-in-class profile, wrote Condulis, from Stifel, in a separate note.Arrowhead intends to file for approval by the end of the year, setting up a potential launch in 2027. Agrawal expects plozasiran to claim 60% of a market opportunity that could reach $6 billion by 2035.A heart drug autopsyIn July, AstraZeneca and Ionis stunned industry watchers when they revealed eplontersen, a medicine theyve been developing, missed the central objective of a Phase 3 study in transthyretin amyloidosis-mediated cardiomyopathy, a progressive and deadly heart condition. At ESC, study investigators presented a detailed autopsy of those results, and Wall Street analysts began assessing the fallout for others with rival medicines.Alnylam already markets one drug called Amvuttra that, like eplontersen, interferes with the production of a protein implicated in the condition. It also has another, next-generation medication known as nucresiran thats in late-stage testing. Eplontersens failure raised doubts about Amvuttras impact on the disease, and heightened skepticism about nucresirans chances of success.William Blair analyst Myles Minter noted how AstraZeneca and Ionis findings call into question the benefits of combination therapy in TTR cardiomyopathy, where these silencer drugs might be used alongside the protein stabilizers patients typically receive. The results also fuel debate around the positioning of available therapies, which include Amvuttra and two branded stabilizers, Pfizers Vyndamax and BridgeBio Pharmas Attruby, according to Minter.In a separate note, Mizuhos Syed wrote that AstraZeneca and Ionis data increases [the] gap between stabilizers and silencers and effectively boosted the case for Attruby. In the placebo group in the failed eplontersen trial, a majority of the patients were on Vyndamax and the level of protein stabilization observed was well short of what was seen in testing of Attruby. Syed argued that the results show why a practitioner would choose Attruby over Vyndamax which will lose market exclusivity in 2031 and suggests investors may be modeling Attruby too conservatively once generics are available, he wrote.Analysts at Oppenheimer, meanwhile, rallied to Alnylams defense, noting that new analyses the company presented Sunday suggest Amvuttra may be more potent than eplontersen and that nucresiran might perform even better in Phase 3 testing. The reason, Oppenheimers Kostas Biliouris contended, is modality differences between Alnylam and Ionis drugs. Both medicines use different approaches RNA interference for Alnylams drugs and antisense oligonucleotide therapy for Ionis to achieve their intended effects. '

Additional Results from ACACIA-HCM Demonstrate Improvements in Cardiac Structure and Diastolic Function in Patients with Non-Obstructive HCM New Analysis of MAPLE-HCM Finds Aficamten Outperformed Metoprolol Across Pre-Trial Treatment Groups in Patients with Obstructive HCM SOUTH SAN FRANCISCO, Calif., Aug. 29, 2026 (GLOBE NEWSWIRE) -- Cytokinetics, Incorporated (Nasdaq: CYTK) today announced that additional results from ACACIA-HCM ( A ssessment C omparing A ficamten to Placebo on C ardiac Endpoints I n A dults with Non-Obstructive HCM ) and MAPLE-HCM ( M etoprolol vs A ficamten in P atients with L VOT Obstruction on E xercise Capacity in HCM ) were presented in a Late Breaking Clinical Session at the European Society of Cardiology (ESC) Congress 2026 in Munich, Germany and simultaneously published in Circulation and the Journal of the American College of Cardiology: Heart Failure , respectively. “The findings from these additional analyses of ACACIA-HCM and MAPLE-HCM elaborate on the primary results from each trial and expand the body of evidence supporting the potential use of aficamten across the spectrum of HCM,” said Stephen Heitner, M.D., Cytokinetics’ Chief Medical Officer. “In particular, the additional results from ACACIA-HCM suggest that the benefits of aficamten in non-obstructive HCM extend beyond exercise capacity and symptom burden to also include improvements in wall thickness and diastolic function, pointing to the potential mechanisms by which aficamten is effective in these patients. Given the lack of approved therapies for non-obstructive HCM, these findings highlight the potential impact aficamten could have on this population independent from relief of left ventricular outflow tract obstruction.” ACACIA-HCM: Effect of Aficamten on Cardiac Structure and Function in Patients with Symptomatic Non-Obstructive HCM Results from a pre-specified exploratory analysis of ACACIA-HCM, the Phase 3 clinical trial of aficamten in patients with symptomatic non-obstructive hypertrophic cardiomyopathy (nHCM), were presented in a Late Breaking Clinical Trial Session and simultaneously published in Circulation . 1 As previously reported, the primary results from ACACIA-HCM showed that treatment with aficamten was associated with significant improvements from baseline to Week 36 compared to placebo in both Kansas City Cardiomyopathy Questionnaire Clinical Summary Score (KCCQ-CSS) and maximal exercise performance (pVO 2 ). This analysis showed that treatment with aficamten also demonstrated improvements in measures of cardiac structure and diastolic function at the time of the primary analysis (36 weeks) and at end of treatment (EOT) (up to 72 weeks; median time to end of treatment = 49 weeks). At Week 36 and at EOT, aficamten significantly improved measures of diastolic function including peak E velocity (p=0.001 and p=0.034, respectively) and septal e’ velocity (p5% of patients and more commonly on MYQORZO than on placebo in the pivotal trial. INDICATIONS AND USAGE MYQORZO is indicated for the treatment of adults with symptomatic obstructive hypertrophic cardiomyopathy (oHCM) to improve functional capacity and symptoms. Please see full Prescribing Information approved in the U.S., including Boxed WARNING. Please see full Summary of Product Characteristics approved in the European Union. About Hypertrophic Cardiomyopathy Hypertrophic cardiomyopathy (HCM) is a disease in which the heart muscle becomes abnormally thick. HCM can be obstructive, when thickened muscle blocks blood flow, or non-obstructive, when blood flow is not blocked but heart function is still affected. In obstructive HCM, the thickening of cardiac muscle leads to the inside of the left ventricle becoming smaller, stiffer and less able to relax and fill with blood. Ultimately, HCM limits the heart’s pumping function, leading to reduced exercise capacity and a variety of symptoms. HCM is the most common monogenic inherited cardiovascular disorder, affecting approximately 1 out of 350 individuals worldwide. 4 Approximately half of patients with HCM have obstructive HCM (oHCM) and half have non-obstructive HCM (nHCM). 5 People with HCM are at high risk of also developing cardiovascular complications including atrial fibrillation, stroke and mitral valve disease. 6 People with HCM are at risk for potentially fatal ventricular arrhythmias and it is one of the leading causes of sudden cardiac death in younger people or athletes. 7 A subset of patients with HCM are at high risk of progressive disease leading to dilated cardiomyopathy and heart failure necessitating cardiac transplantation. About Cytokinetics Cytokinetics is a specialty cardiovascular biopharmaceutical company, building on its over 25 years of pioneering scientific innovations in muscle biology, and advancing a pipeline of potential new medicines for patients suffering from diseases of cardiac muscle dysfunction. Cytokinetics’ MYQORZO ® ( aficamten ) is a cardiac myosin inhibitor approved in the approved in the U.S., China, European Union and United Kingdom for the treatment of adults with symptomatic obstructive hypertrophic cardiomyopathy (oHCM). Following positive results in ACACIA-HCM, a Phase 3 clinical trial of aficamten in patients with non-obstructive HCM (nHCM), the company plans to submit a Supplemental New Drug Application in Q4 2026. Cytokinetics is also developing omecamtiv mecarbil , an investigational cardiac myosin activator for the potential treatment of patients with heart failure with severely reduced ejection fraction and ulacamten , an investigational cardiac myosin inhibitor for the potential treatment of heart failure with preserved ejection fraction, while continuing pre-clinical research and development in muscle biology. For additional information about Cytokinetics, visit and follow us on X , LinkedIn , Facebook and YouTube . Forward-Looking Statements This press release contains forward-looking statements for purposes of the Private Securities Litigation Reform Act of 1995 (the “Act”). Cytokinetics disclaims any intent or obligation to update these forward-looking statements and claims the protection of the Act’s Safe Harbor for forward-looking statements. Examples of such statements include, but are not limited to, statements relating to our ability to obtain regulatory approval for aficamten in nonobstructive hypertrophic cardiomyopathy in any jurisdiction by any particular date, if ever, the number of patients comprising the eligible treatment population for aficamten , or market acceptance of aficamten for the treatment of nonobstructive hypertrophic cardiomyopathy. Such statements are based on management’s current expectations, but actual results may differ materially due to various risks and uncertainties, including, but not limited to, potential difficulties or delays in the development, testing, regulatory approvals for trial commencement, progression or product sale or manufacturing of Cytokinetics’ drug candidates that could slow or prevent clinical development or product approval; Cytokinetics’ drug candidates may have adverse side effects or inadequate therapeutic efficacy; the FDA or foreign regulatory agencies may delay or limit Cytokinetics’ ability to conduct clinical trials; Cytokinetics may be unable to obtain or maintain patent or trade secret protection for its intellectual property; standards of care may change, rendering Cytokinetics’ drug candidates obsolete; and competitive products or alternative therapies may be developed by others for the treatment of indications Cytokinetics’ drug candidates and potential drug candidates may target. For further information regarding these and other risks related to Cytokinetics’ business, investors should consult Cytokinetics’ filings with the Securities and Exchange Commission. CYTOKINETICS® and the CYTOKINETICS C-shaped logo are registered trademarks of Cytokinetics in the U.S. and certain other countries. MYQORZO® is a registered trademark of Cytokinetics in the U.S., the European Union and the United Kingdom. References Maron MS, et al. Global Efficacy of Aficamten in Nonobstructive Hypertrophic Cardiomyopathy: Results From ACACIA-HCM. Circ . 2026 Dominguez, F. Efficacy of Aficamten vs Metoprolol According to Pretrial Beta-Blocker Treatment in Obstructive Hypertrophic Cardiomyopathy. JACC: HF. 2026. Maron, MS, et al. Aficamten for Symptomatic Obstructive Hypertrophic Cardiomyopathy. N Engl J Med. doi:10.1056/NEJMoa2401424 Tsenov et al. Healthcare access, symptom burden, and psychological impact in hypertrophic cardiomyopathy: a multinational patient-driven survey. Int J Cardiol Cardiovasc Risk Prev2025 Aug 4;27:200485. doi: 10.1016/j.ijcrp.2025.200485 Butzner M, et al. Epidemiology of Hypertrophic Cardiomyopathy in the United States From 2016 to 2023. JACC Adv. 2026. 2026;5(2):102552. doi:10.1016/j.jacadv.2025.102552 Gersh, B.J., Maron, B.J., Bonow, R.O., Dearani, J.A., Fifer, M.A., Link, M.S., et al. 2011 ACCF/AHA guidelines for the diagnosis and treatment of hypertrophic cardiomyopathy. A report of the American College of Cardiology Foundation/American Heart Association Task Force on practice guidelines. Journal of the American College of Cardiology and Circulation, 58, e212-260. Hong Y, Su WW, Li X. Risk factors of sudden cardiac death in hypertrophic Contact: Cytokinetics Diane Weiser Senior Vice President, Corporate Affairs (415) 290-7757