Hengrui Pharma and Braveheart Bio Announce Positive Phase 2 Results with HRS/BHB-1893 in Obstructive Hypertrophic Cardiomyopathy

Results of dose-ranging study suggest potential for best-in-class clinical profile across efficacy, safety and ease of use, including simplified dosing regimen with minimal to no titration necessary

HRS-1893 treatment resulted in rapid and substantial reductions in left ventricular outflow tract gradient (Valsalva LVOT-G complete gradient response (<30 mmHg) of up to 86%) with minimal change in left ventricular ejection fraction (LVEF; range of decrease between 1.8% and 2.7%)

Data highlighted in a late-breaking featured clinical research presentation at the American College of Cardiology's Annual Scientific Session & Expo

SHANGHAI and SAN FRANCISCO, March 30, 2026 /PRNewswire/ -- Hengrui Pharma (Hengrui), and Braveheart Bio today announced results from a multi-center, randomized, open-label Phase 2 dose-ranging study evaluating HRS-1893 (also known as BHB-1893), an investigational next-generation cardiac myosin inhibitor, in patients with obstructive hypertrophic cardiomyopathy (oHCM). In the 42 patient study, HRS-1893 treatment resulted in rapid and substantial reductions in left ventricular outflow tract gradient (LVOT-G), an established measure of cardiac obstruction.

"The results of this study build on the clinical data observed to date and reinforce BHB/HRS-1893's potential as a highly differentiated treatment option for patients with oHCM," said Sheng Qi, M.D., Executive Director and Head of Cardiovascular, Hengrui Pharma. "We look forward to further clinical development and continued partnership with Braveheart as we aim to deliver improved treatment options for global patients."

"We believe these results are consistent with a best-in-class clinical profile, with the potential to become a novel, promising treatment option for patients with obstructive hypertrophic cardiomyopathy," said Travis Murdoch, M.D., Chief Executive Officer and President, Braveheart Bio. "The emerging clinical efficacy profile, along with the potential for a highly simplified dosing regimen, may address key limitations of current therapies and unlock adoption by a broad population of patients with urgent needs. These results support our planned initiation of a global pivotal clinical study in 2026."

The multi-center, randomized, open-label Phase 2 dose-ranging study (NCT06516068) of 42 patients was designed to measure efficacy and safety of BHB/HRS-1893 and to evaluate dose regimen options that could shorten the time to an effective dose. Patients were randomized 1:1:1 to receive oral BHB/HRS-1893 20 mg twice daily (potentially titrated up to 60 mg; Group 1), 40 mg twice daily (potentially titrated up to 80 mg; Group 2) or 40 mg once-daily (potentially titrated up to 120 mg; Group 3), for 12 weeks. The study design included the option for individual dosage adjustment based on evaluation of left ventricular ejection fraction (LVEF) and Valsalva LVOT-G. The primary endpoint was change in Valsalva LVOT-G from baseline to Week 12. 

BHB/HRS-1893 treatment resulted in rapid and substantial reductions in LVOT-G with minimal change in LVEF across dose groups. Range of complete Valsalva LVOT-G response (<30 mmHg) was between 50% and 86% and the range of LVEF decrease was between 1.8% and 2.7%. BHB/HRS-1893 displayed rapid onset of effect, with the average Valsalva LVOT-G below 30 mmHg as early as day 5. The study found 89% of patients well served at a 40 mg or 60 mg twice-daily dose regimen, with minimal to no titration required to achieve the target dose. Importantly, all patients were titrated to a final dose based solely on gradient reduction below LVOT-G <30 mmHg. BHB/HRS-1893 treatment also demonstrated improvements in key secondary and exploratory measures in Group 2, the dose selected for open-label extension (OLE), including increase in pVO2 of 1.0 mL/kg/min, KCCQ-CSS of 10.5 points, and reduction in NT-proBNP of 88%. 

All 42 patients enrolled in the OLE part of the study and continued to receive administration of BHB/HRS-1893. At Week 39 of the OLE, the complete Valsalva LVOT-G response rate was 88%.

BHB/HRS-1893 was generally well tolerated, and no new safety signals were identified in the 12-week study period. Reported adverse events were mild to moderate in severity, and no adverse events led to treatment interruption or discontinuation. No patients experienced ejection fraction values below 55% during the 12-week study period.

Results of the study were highlighted in a late-breaking featured clinical research presentation at the American College of Cardiology's Annual Scientific Session & Expo.

About Hypertrophic Cardiomyopathy

HCM is among the most common rare diseases, affecting approximately 1 in 500 individuals in the United States. HCM can lead to heart failure, stroke or sudden cardiac death, including in young adults and athletes who may often live with the disease undetected.

In HCM, overactive myosin can cause excessive contraction of the heart, resulting in the heart muscle becoming abnormally thick, particularly in the left ventricle—the heart's main pumping chamber. This leads to symptoms like shortness of breath, chest pain, fatigue and fainting, which typically worsen with physical activity and can significantly limit patients' ability to exercise, work or perform routine tasks.

Two-thirds of patients with HCM have oHCM, where the thickened muscle creates a blockage in the heart's main pumping chamber, making it harder for blood to flow out to the body with each heartbeat. Approximately one-third of patients with HCM have non-obstructive hypertrophic cardiomyopathy (nHCM), where there is no obstruction, but the muscle is thickened, limiting proper heart function. 

About HRS-1893/BHB-1893

HRS-1893 (also known as BHB-1893) is a selective, small-molecule, cardiac myosin inhibitor engineered to improve heart performance in patients with HCM. By modulating cardiac contractility, HRS-1893 aims to address the underlying pathophysiology of HCM while maintaining cardiac output.

HRS-1893 has undergone extensive clinical development, including a dose-ranging Phase 2 study in symptomatic oHCM, an ongoing Phase 2 study in nHCM, multiple clinical pharmacology studies including a bridging study in Australia and an ongoing Phase 3 study in oHCM in China (NCT07021976). Braveheart Bio entered into an exclusive worldwide license agreement with Hengrui Pharma for the development, manufacture and commercialization of HRS-1893, outside of Mainland China, the Hong Kong SAR, the Macao SAR and Taiwan Region.

About Hengrui Pharma

Hengrui Pharma is an innovative, global pharmaceutical company dedicated to the research, development and commercialization of high-quality medicines to address unmet clinical needs. Its therapeutic areas of focus include oncology, metabolic and cardiovascular diseases, immunological and respiratory diseases, and neuroscience. Driven by a patient-focused philosophy since its founding in 1970, Hengrui Pharma remains committed to advancing human health by striving to conquer diseases, improve health, and extend lives through the power of science and technology.

About Braveheart Bio

Braveheart Bio is a late clinical-stage biotechnology company developing novel therapeutics for hypertrophic cardiomyopathy and related conditions. The company is backed by experienced life science investors including Andreessen Horowitz (a16z Bio + Health), Forbion, OrbiMed, Enavate Sciences (a platform of Patient Square Capital) and Frazier Life Sciences. Braveheart is advancing BHB-1893 through late-stage clinical development with the goal of establishing a new standard of care. For more information, visit www.braveheart.bio.

Contacts

Contact Information for Hengrui

Media
Yizhen Yang
Assistant Director of Public Relations and Communications
[email protected]

Investor Relations
Lina Zhang
Head of Capital Markets and Securities Affairs
[email protected] 

Contact Information for Braveheart Bio

Media
FGS Global
[email protected]

Investors
Paul Rickey, CFO
[email protected]

SOURCE Braveheart Bio