Sirius Therapeutics announces NMPA Approval to Begin Phase 1 Clinical Trial in China of NovelsiRNA Therapy for Hyperlipoproteinemia(a)

San Diego and Shanghai, March 20, 2025 – Sirius Therapeutics today announced that the National Medical Products Administration (NMPA) of China has approved the company's Investigational New Drug (IND) application to begin the first-in-human Phase 1 clinical trial of SRSD216, a novel small interfering RNA (siRNA) therapeutic designed to manage hyperlipoproteinemia(a), or elevated levels of lipoprotein(a).

Numerous genetic and epidemiologic studies have demonstrated an association between elevated levels of lipoprotein(a) and atherosclerotic cardiovascular disease (ASCVD). The exceptional durability of SRSD216's pharmacodynamic effects and benign safety profile in preclinical studies suggest that this novel siRNA could represent a substantial step forward in the prevention of ASCVD.

Dr. Curt Bradshaw, Chief Scientific Officer commented, "This milestone further validates the strength of our platform to discover and efficiently develop a new generation of siRNA therapeutics. SRSD216 is the third Sirius-discovered siRNA therapeutic to enter clinical development since the company was founded in 2021."

Dr. Qunsheng Ji, Chief Executive Officer, added, "The NMPA approval is a critical step in the development of SRSD216. Our team has worked diligently to achieve this milestone as part of Sirius’ broader strategy to develop innovative treatments for cardiometabolic diseases. The company is now preparing to initiate Phase 1 clinical trial to further evaluate the safety and efficacy of SRSD216 in human subjects."

About ASCVD and hyperlipoproteinemia(a)

Atherosclerotic cardiovascular disease (ASCVD) is the most common cause of death worldwide. Dyslipidemia is regarded as a key contributor to the development of ASCVD. While low-density lipoprotein cholesterol (LDL-c) has been considered the primary lipid indicator and target for intervention for decades, numerous studies have identified lipoprotein(a) [Lp(a)] as an independent risk factor for ASCVD. Moreover, Lp(a) is not modified by age, diet, or exercise and currently available pharmacotherapies for dyslipidemia have only modest effects on Lp(a), highlighting a significant clinical unmet need for agents that directly target Lp(a).

About SRSD216

SRSD216 is a novel double-stranded small interfering ribonucleic acid (siRNA) that specifically modulates the LPA gene, decreasing hepatic Apo(a) production and reducing circulating Lp(a) levels. Preclinical in vivo studies have demonstrated a near 100% reduction in Lp(a) levels over 6 months, with no meaningful safety findings reported after a single subcutaneous dose.

About Sirius Therapeutics

Sirius is a clinical stage biotech company developing innovative siRNA therapies for global markets. We are dedicated to discovering and developing new treatment options for cardiovascular and cerebrovascular disease and translating siRNA technology into transformative medicine for chronic disease patients. Our most advanced products are SRSD107 for the treatment of thromboembolic disorders, and SRSD101 for the treatment of dyslipidemia.

Founded in 2021 by a world-class leadership team and investors, Sirius has established an innovation center inthe United States and translational medicine center in China. Sirius has raised nearly US$100 million funding to date from OrbiMed, Creacion Ventures, Hankang Capital, and Delos Capital. Learn more at www.siriusrna.com