Arrowhead Begins Dosing in Phase 1 Study of ARO-AAT for Treatment of Alpha-1 Liver Disease

Arrowhead Pharmaceuticals Inc. (NASDAQ: ARWR) today announced that it has dosed the first subjects in a Phase 1 clinical study of ARO-AAT, which is being developed as treatment for a rare genetic liver disease associated with alpha-1 antitrypsin deficiency. ARO-AAT is the first clinical candidate to utilize Arrowhead’s proprietary Targeted RNAi Molecule (TRiMTM) technology. The second candidate, ARO-HBV, which is being developed as a potentially curative therapy for patients with chronic hepatitis B virus (HBV) infection, is also on schedule to dose the first subjects in a Phase 1/2 study at the end of March.

Bruce Given, M.D., chief operating officer and head of R&D at Arrowhead said, “There remains no adequate treatment for alpha-1 liver disease, other than transplant. ARO-AAT is designed to reduce the liver production of the inflammatory Z-AAT protein, which is believed to be the cause of progressive liver disease in AATD patients. This reduction may stop the progression of liver disease and possibly even allow the liver to recover and heal existing damage. This would represent a significant and much-needed breakthrough for patients.”

The study, AROAAT1001 (NCT03362242), is a Phase 1 single- and multiple-ascending dose study to evaluate the safety, tolerability, pharmacokinetics, and effect of ARO-AAT on serum alpha-1 antitrypsin levels in healthy adult volunteers. The study is designed to include up to 5 cohorts of 8 subjects per cohort who will receive placebo or ARO-AAT at doses of 35, 100, 200, 300, or 400 mg.

About Arrowhead Pharmaceuticals

Arrowhead Pharmaceuticals develops medicines that treat intractable diseases by silencing the genes that cause them. Using a broad portfolio of RNA chemistries and efficient modes of delivery, Arrowhead therapies trigger the RNA interference mechanism to induce rapid, deep, and durable knockdown of target genes. RNA interference, or RNAi, is a mechanism present in living cells that inhibits the expression of a specific gene, thereby affecting the production of a specific protein. Arrowhead’s RNAi-based therapeutics leverage this natural pathway of gene silencing.

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Source: Arrowhead Pharmaceuticals, Inc.

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