Sanofi has entered into an asset purchase agreement to acquire Greater China rights to plozasiran, Arrowhead Pharmaceuticals' investigational RNA interference therapeutic for rare lipid disorders, in a deal worth up to $395 million. The transaction involves Visirna Therapeutics, Arrowhead's majority-owned subsidiary focused on developing cardiometabolic candidates in the Chinese market.
Under the agreement, Visirna will receive an upfront payment of $130 million from Sanofi, with additional milestone payments of up to $265 million contingent on regulatory approvals across various indications in mainland China. Arrowhead retains eligibility for royalties on net commercial sales in Greater China through its licensing arrangement with Visirna.
Successful Phase 3 Trial Results Drive Deal
The acquisition follows positive results from Visirna's completed Phase 3 clinical trial (CTR20231418/NCT05902598) of plozasiran in Chinese patients with familial chylomicronemia syndrome (FCS). The study successfully met its primary efficacy endpoint and all key secondary endpoints, providing the foundation for regulatory submission.
Visirna subsequently filed a New Drug Application with China's National Medical Products Administration (NMPA) for plozasiran in FCS treatment, receiving official acceptance in January 2025. The drug has been granted both Breakthrough Therapy Designation for FCS patients and Priority Review Designation by the China NMPA, reflecting its potential to address significant unmet medical need.
"The team at Visirna understand the intricacies of China's clinical, regulatory, and commercial environment and have done impressive work moving plozasiran through clinical studies and into the regulatory submission and review process," said Christopher Anzalone, Arrowhead's President and CEO.
First-in-Class RNAi Mechanism
Plozasiran, previously designated ARO-APOC3, represents a first-in-class investigational RNA interference therapeutic designed to reduce production of apolipoprotein C-III (APOC3). APOC3 serves as a key regulator of triglyceride metabolism and is a component of triglyceride-rich lipoproteins (TRLs).
The therapeutic mechanism involves targeting APOC3, which normally increases triglyceride levels by inhibiting breakdown of TRLs by lipoprotein lipase and preventing uptake of TRL remnants by liver receptors. By reducing APOC3 levels, plozasiran aims to decrease triglycerides and restore lipid profiles to more normal ranges.
Broad Clinical Development Program
Beyond FCS, plozasiran is being investigated across multiple lipid disorders through the comprehensive SUMMIT clinical program. This includes the PALISADE Phase 3 study in FCS patients, the SHASTA Phase 2 and Phase 3 studies in severe hypertriglyceridemia (SHTG), and the MUIR Phase 2 and Phase 3 studies in mixed hyperlipidemia.
Clinical data across multiple studies have demonstrated plozasiran's ability to reduce triglycerides and multiple atherogenic lipoproteins in patients with FCS, SHTG, and mixed hyperlipidemia. The drug has been generally well tolerated, with treatment-emergent adverse events for the proposed 25 mg marketing dose including COVID-19, upper respiratory tract infection, headache, Type 2 diabetes mellitus, and abdominal pain.
Regulatory Recognition and Global Development
Plozasiran has received significant regulatory recognition for FCS treatment, including Breakthrough Therapy Designation, Orphan Drug Designation, and Fast Track Designation from the U.S. Food and Drug Administration. The European Medicines Agency has granted Orphan Medicinal Product Designation for the same indication.
The investigational therapy has been submitted for marketing authorization to treat FCS across multiple global regulatory authorities, though it has not yet received approval for any disease indication.
Wayne Shi, President of Sanofi Greater China, emphasized the strategic importance of the acquisition: "Plozasiran has shown considerable potential in studies across diverse patient populations where serious illness is caused by elevated triglycerides. With our strong presence in China's cardiometabolic field, we now look forward to bringing it forward to address unmet need."
The deal represents a significant validation of Visirna's China-focused development strategy since its 2022 founding as an Arrowhead subsidiary. Visirna was established to advance four of Arrowhead's investigational cardiometabolic candidates specifically for the Greater China market, leveraging local expertise in clinical development and regulatory navigation.
