Sanofi Buys Rights in Greater China to Arrowhead Subsidiary’s Rare Cardiometabolic Candidates

Rare Daily Staff

Sanofi will pay $130 million upfront and up to an additional $265 million in potential regulatory milestones to Arrowhead Pharmaceuticals’ majority-owned subsidiary, Visirna Therapeutics, to develop and commercialize four of Arrowhead’s experimental cardiometabolic candidates in Greater China.

Under the terms of the agreement, Sanofi will acquire rights to develop and commercialize plozasiran, Arrowhead’s experimental, first-in-class RNA interference therapeutic candidate designed to reduce the production of apolipoprotein C-III (APOC3), as a potential treatment for familial chylomicronemia syndrome (FCS), a rare genetic disorder in which the body is unable to break down dietary fats, and severe hypertriglyceridemia (SHTG), in Greater China.

Sanofi will receive an exclusive license to develop and commercialize plozasiran in Greater China from Visirna Therapeutics, offering a potential treatment to people living with elevated triglycerides.

Plozasiran, previously called ARO-APOC3, is an experimental RNA interference therapeutic designed to reduce production of apolipoprotein C-III (APOC3), which is a component of triglyceride-rich lipoproteins (TRLs) and a key regulator of triglyceride metabolism. APOC3 increases triglyceride levels in the blood by inhibiting the breakdown of TRLs by lipoprotein lipase and the uptake of TRL remnants by receptors in the liver. The goal of treatment with plozasiran is to reduce the level of APOC3, thereby reducing triglycerides and restoring lipids to more normal levels.

In multiple clinical studies, plozasiran has demonstrated reductions in triglycerides and multiple atherogenic lipoproteins in patients with FCS, SHTG, and mixed hyperlipidemia.

Plozasiran has been generally well tolerated to date, with treatment-emergent adverse events reported that generally reflect the comorbidities and underlying conditions of the study populations. Across clinical studies and study populations, the most frequently reported treatment-emergent adverse events for the 25 mg dose proposed for marketing approval were COVID-19, upper respiratory tract infection, headache, type 2 diabetes mellitus, and abdominal pain.

Visirna has completed a phase 3 clinical trial of plozasiran in Chinese patients with FCS, which successfully met its primary efficacy endpoint and all key secondary endpoints. Visirna subsequently submitted a New Drug Application for plozasiran to the National Medical Products Administration in China for the treatment of FCS and received official acceptance in January 2025. Plozasiran has also been granted Breakthrough Therapy Designation for the treatment of patients with FCS and Priority Review Designation by the China NMPA.

“When we founded Visirna in 2022, we believed that Greater China represented an important potential future market for multiple programs in Arrowhead’s pipeline of investigational RNAi-based candidates for cardiometabolic diseases,” said Christopher Anzalone, Arrowhead president and CEO. “The team at Visirna understands the intricacies of China’s clinical, regulatory, and commercial environment and has done impressive work moving plozasiran through clinical studies and into the regulatory submission and review process.”