Aficamten

Braveheart Bio said Monday that the heart muscle therapy it licensed from China’s Jiangsu Hengrui Pharmaceuticals has succeeded in a mid-stage trial for the same condition in which Cytokinetics recently scored a late-stage win . The trial of Braveheart and Hengrui’s pill, which is known as BHB-1893 or HRS-1893, was conducted in China and enrolled 84 patients with non-obstructive hypertrophic cardiomyopathy (nHCM). Patients were titrated up to either 40 mg (low dose) or 60 mg (high dose) twice daily for three months, or given placebo. Results were presented at Heart Failure 2026, the annual meeting of the Heart Failure Association of the European Society of Cardiology in Barcelona. The high-dose group demonstrated a placebo-adjusted improvement of 5.5 points in KCCQ-CSS, a scale that measures the severity of nHCM symptoms including shortness of breath, fatigue and the ability to do daily activities. This isn’t bad: Cytokinetics’ drug Myqorzo managed a delta over placebo of three points on this scale when its data were released a week ago. It should be noted though that the Myqorzo data came from a Phase 3 trial, and later-stage studies tend to yield less pronounced efficacy data since their designs are more stringent. And comparing across different trials is far from ideal anyway. Of the high-dose patients in Braveheart’s trial, 52% had a KCCQ-CSS improvement of at least 20 points, compared with 21% of the placebo subjects. On another important measure of efficacy called peak oxygen uptake (pVO2), which assesses patients’ ability to exercise, the high-dose group had an improvement of 2.1 mL/kg/min — 0.9 mL/kg/min more than those given placebo. Again this compares well with Cytokinetics’ drug, which yielded a placebo-adjusted difference of 0.67 mL/kg/min. HRS/BHB-1893 also improved measures of heart muscle health and levels of cardiac biomarkers. Braveheart said there were no severe side effects in the trial and no adverse events caused patients to interrupt treatment with HRS/BHB-1893 or quit taking it altogether. Serious side effects including cellulitis, otolithiasis (an inner ear problem that can cause feelings of vertigo), and atrial fibrillation were seen in three patients taking the pill; all were assessed as unrelated to the drug. Four patients in the trial had to have their dose reduced as they had a temporary drop in their left ventricular ejection fraction (LVEF) beneath 50%. LVEF gives an idea of how well the heart pumps blood. In nHCM, patients’ heart muscle becomes thickened, impairing the organ’s function — but not in such a way that it blocks the outflow of blood from the heart. People with the other form of the disorder, obstructive HCM, do have a blockage. Braveheart reported mid-stage data in the obstructive form in March, showing that HRS/BHB-1893 improved patients’ heart function. The US biotech said it is planning a global registrational study for HRS/BHB-1893 in nHCM. The drug is a cardiac myosin inhibitor, as are Myqorzo and Bristol Myers Squibb’s Camzyos. Camzyos is approved for oHCM but failed in its pivotal trial in nHCM. Braveheart licensed most of the global rights to HRS/BHB-1893 in September, paying Hengrui $65 million upfront. Editor’s note: This article was updated to clarify the location of Braveheart and Hengrui’s trial.

Braveheart Bio and Hengrui Pharma on Monday reported new study data suggesting their partnered cardiac myosin inhibitor BHB-1893 (HRS-1893) may have potential beyond simply easing symptoms in hypertrophic cardiomyopathy (HCM).At the Heart Failure 2026 congress, the companies presented results from a Phase II study of 84 patients with symptomatic non-obstructive HCM, a form of the disease that affects about half of the HCM population. Patients treated with BHB-1893 improved across a number of measures, including symptoms, exercise capacity, cardiac biomarkers and echocardiographic measures.Specifically, in the high-dose arm, patients achieved a placebo-adjusted 5.5-point gain on the Kansas City Cardiomyopathy Questionnaire Clinical Summary Score (KCCQ-CSS), while 52% saw at least a 20-point improvement, compared to 21% for placebo. Exercise capacity improved as well, with patients titrated to 60 mg twice daily posting a placebo-adjusted gain of 0.9 mL/kg/min in peak oxygen consumption (pVO2).Structural reverse remodellingThere were also signals of improved heart relaxation and structure among higher-dose recipients. The left atrial volume index (LAVI) fell by 7.1 mL/m² from baseline, versus essentially no change on placebo, while left ventricular mass (LVMI) decreased by 17.4 g/m² in the treatment arm compared to an increase of 3.2 g/m² for placebo. Heart wall thickness declined by 3.3 mm, versus 0.1 mm for placebo.Non-obstructive HCM lacks the left ventricular outflow tract (LVOT) gradient seen in obstructive disease; that's where a pressure difference is created when blood is trying to leave the heart by squeezing through a narrowed "obstructed" exit. In obstructive HCM, drugs can improve symptoms by relieving the blockage that is causing the gradient, making it harder to tell whether they are actually changing disease biology.However, in non-obstructive HCM, that specific confounder doesn't exist because there is no LVOT gradient to relieve."The structural reverse remodelling toward normal observed here is a compelling early signal that BHB-1893 may be modifying the underlying disease in non-obstructive HCM, in addition to helping manage the condition," said Anjali Owens, a member of Braveheart's clinical advisory board.Meanwhile, CEO Travis Murdoch said the placebo-controlled design boosts his confidence in the findings. "The fact that we didn't see movement in the placebo arm, but we saw…a dose-dependent movement, which in many cases was statistically significant, really gave us encouragement that this could continue to play out in a meaningful way in a larger pivotal study," he told FirstWord.Murdoch also pointed to the biomarker response that appeared "more rapid" and "deeper" than what has been seen previously. NT-proBNP, a marker associated with diastolic wall stress, fell roughly 68% to 69%, while cardiac troponin I, a marker of myocardial injury, declined 55% to 60%, both statistically significant against placebo.Braveheart and Hengrui said BHB-1893 was generally well tolerated, with no severe treatment-related adverse events and no discontinuations tied to the drug. As cardiac myosin inhibitors work by intentionally reducing the force of heart contraction, researchers also looked at the incidence of left ventricular ejection fraction (LVEF) <50%. Four treated patients (7%) experienced temporary declines in LVEF requiring dose reductions, though all recovered to above 50% after adjustment.Cytokinetics' recent successLast week, Cytokinetics reported that its drug Myqorzo (aficamten) became the first cardiac myosin inhibitor to succeed in a Phase III non-obstructive HCM trial, hitting dual endpoints in the ACACIA-HCM study (see – Spotlight On: Cytokinetics could double Myqorzo's reach with non-obstructive HCM win).That result contrasted with the setback suffered by Bristol Myers Squibb last year when Camzyos (mavacamten) failed to meet the main goals of the Phase III ODYSSEY-HCM study in the same indication.Both Myqorzo and Camzyos are already approved for obstructive HCM, with Camzyos generating growing sales since its 2022 launch, including hitting blockbuster status last year with revenues of around $1.1 billion, while Myqorzo won approvals in China and the US in late 2025 followed by Europe earlier this year.Pivotal study plansBraveheart is hoping BHB-1893 can be a differentiated entrant in the space. The drug was originally discovered by Hengrui, which out-licensed ex-China rights to Braveheart last year in a deal worth up to $1.1 billion. This past March, Braveheart and Hengrui unveiled Phase II data for BHB-1893 in obstructive HCM showing complete LVOT gradient response ranging from 50% to 86% with minimal changes in LVEF.Hegnrui is running a Phase III study of the drug in obstructive HCM in China that should readout towards the end of the year, according to ClinicalTrials.gov. Braveheart is in the middle of ramping up for pivotal studies as well, initially in the obstructive form of the disease slated for this year. It is also planning to have discussions with regulators about initiating a non-obstructive study, which they hope to begin this year as well.