Yiming Angke's Subsidiary Immunecare Achieves Dual Clinical Milestones for IMC-003 in Pulmonary Arterial Hypertension: First PAH Patient Enrolled and SAD/MAD Dose Groups Fully Enrolled

August 25, 2026 | Shanghai, China

For patients with pulmonary arterial hypertension—a rare, progressive disease often called "cardiovascular cancer"—treatment options remain brutally limited. Now a Shanghai biotech is betting its molecular engineering can do better than the only approved therapy on the market.

Yiming Angke Biomedical Technology (Shanghai) Co., Ltd. (HKEX: 01541.HK) announced Monday that its subsidiary Immunecare Biopharmaceuticals (Shanghai) Co., Ltd. has reached two critical clinical milestones for IMC-003 (also known as IMM72), an ActRIIA-Fc fusion protein targeting pulmonary arterial hypertension (PAH).

The first patient has been enrolled and dosed in a Phase Ib/IIa trial in PAH patients. Separately, all dose groups in both the single ascending dose (SAD) and multiple ascending dose (MAD) Phase I studies in postmenopausal healthy women have completed enrollment.

The dual progress marks the transition of IMC-003 from healthy-volunteer safety testing into actual patient validation—a pivotal step for any drug candidate.

Clean Safety Profile So Far

The Phase I program tested IMC-003 across seven SAD dose groups ranging from 0.03 mg/kg to 8.0 mg/kg, and four MAD dose groups from 0.1 mg/kg to 2.0 mg/kg. Each MAD group enrolled eight subjects.

The results: zero dose-limiting toxicities (DLTs) across all seven SAD groups. The vast majority of drug-related adverse events were Grade 1. No drug-related adverse events of Grade 3 or higher were observed.

In the MAD portion, all adverse events were Grade 1 or 2. No adverse events involving hemoglobin elevation of Grade 2 or higher occurred. The first three dose groups reported no DLTs. The fourth dose group—whose enrollment of all eight subjects was completed on August 17, 2026—has not yet reached its safety observation endpoint.

Differentiation by Design

IMC-003 targets the same pathway as Winrevair (sotatercept), the only approved ActRIIA-Fc fusion protein for PAH, made by Merck. But Immunecare says its molecule is engineered to be meaningfully different.

The company modified the extracellular domain of the ActRIIA receptor to enhance binding and blocking activity against Activin A—the key ligand driving the disease. Preclinical data show IMC-003's binding and signal-blocking activity is more than five times that of sotatercept.

In pharmacodynamic studies, the effect on follicle-stimulating hormone (FSH) showed a clear dose-response relationship from 0.03 mg/kg to 4.0 mg/kg, plateauing at the 4.0 mg/kg dose. Critically, the drug exposure required to achieve this pharmacodynamic effect was far lower than what has been reported for Winrevair at equivalent efficacy.

In animal models of PAH—both the Sugen5416-hypoxia and monocrotaline (MCT) models—IMC-003 significantly improved right ventricular systolic pressure (RVSP) and pulmonary arteriolar wall area, outperforming sotatercept.

The company argues that higher selectivity for Activin A could translate to a better safety profile in patients, potentially reducing bleeding risk—a known concern with the current standard of care.

What Comes Next

"Today marks a dual key milestone in Immunecare's R&D progress in non-oncology diseases," said Dr. Tian Wenzhi, Chairman, CEO and CSO of Yiming Angke and founder of Immunecare. "From healthy subjects to PAH patients, the clinical development of IMC-003 is advancing steadily and efficiently."

Dr. Tian said the company expects to obtain complete Phase I data within 2026 and accelerate into Phase II clinical development.

The PAH patient trial—the Phase Ib/IIa study—enrolled its first patient on June 30, 2026. That study will be the real test of whether IMC-003's preclinical promise holds up in the patients who need it most.

Immunecare, founded in January 2024 in Shanghai, is also building a broader pipeline. Its bispecific antibody IMC-004 targets ActRIIA and RANKL for osteoporosis. In the metabolic space, the company is preparing IND applications for IMC-011 (IMM91), an anti-latent GDF8 monoclonal antibody showing muscle-building effects in preclinical studies, and IMC-015 (IMM9101), a GDF8×ActRII bispecific antibody designed to simultaneously reduce fat and build muscle in obese patients.

Yiming Angke, the parent company, listed on the Hong Kong Stock Exchange on September 5, 2023. Founded in June 2015 in Shanghai's Zhangjiang Hi-Tech Park, the company has built its reputation on tumor immunotherapy—systematically leveraging both innate and adaptive immune systems. The push into PAH through Immunecare represents a strategic expansion beyond oncology.

The question now is whether a molecule engineered to be five times more potent than the incumbent can deliver on that promise in patients—and whether it can do so safely enough to win over physicians who have learned to manage Winrevair's trade-offs.

Disclaimer: This article contains forward-looking statements based on the company's current views and assumptions. Actual results may differ materially from those projected. All clinical data referenced herein are from the company's press release dated August 25, 2026.