Arrowhead Advances Zodasiran Into Phase 3 HoFH Study, Signaling Long-Term Growth Potential

Arrowhead Pharmaceuticals, Inc. (ARWR) announced an update on their ongoing clinical study.

Arrowhead Pharmaceuticals, Inc. is launching a Phase 3 study called SPRUCE to test its drug zodasiran in teens with a rare, severe cholesterol disorder known as homozygous familial hypercholesterolemia. The goal is to see if the drug can safely cut bad cholesterol in patients who remain high risk despite strong existing treatment.

The treatment is zodasiran, also known as ARO-ANG3, given as an injection under the skin. It is designed to lower LDL cholesterol by targeting a specific pathway in the body that drives very high levels in this rare disease.

The trial is an interventional study with one treatment group and no control arm, which is common in rare, serious conditions. It is open-label, so both doctors and patients know they are getting zodasiran, and the main aim is to treat and measure benefit and risk in real-world use.

The study is listed as not yet recruiting and was first submitted on March 11, 2026, which signals the formal start of the regulatory process. The listing was last updated on March 19, 2026, showing the protocol is active and the company is preparing to begin enrollment and execution.

For investors, this update confirms Arrowhead is moving its cardiometabolic pipeline into late-stage testing, which can support long-term growth expectations if results are strong. It also places Arrowhead more clearly in the rare-lipid space alongside players working on HoFH and related conditions, potentially lifting sentiment around its broader platform.

While near-term revenue impact is limited, a successful Phase 3 in this small but high-need market could validate the drug and the underlying RNA-based approach. That validation can improve Arrowhead’s strategic options, from partnerships to pricing power, and may influence how the market values similar assets in the sector.

The SPRUCE study of zodasiran in adolescent HoFH patients is now formally registered and in the setup phase, with ongoing updates and fuller details available on the ClinicalTrials portal.

To learn more about ARWR’s potential, visit the Arrowhead Pharmaceuticals, Inc. drug pipeline page.