Arrowhead refills its quiver

Arrowhead Pharmaceuticals Inc.’s tox blowup in 2016 set back its clinical timelines, but it also prompted the company to bring a more versatile platform online faster than originally planned. Early data from replacement candidates suggest management’s choice to scrap its initial programs and instead accelerate development of a next-generation RNAi delivery platform is paying off.

On Sept. 6 at the World Gastroenterologists Summit, the company reported the first efficacy data for a candidate from its new subcutaneous Targeted RNAi Molecule (TRiM) platform. In a Phase I/II study in patients with chronic HBV, 100 mg of ARO-HBV lowered hepatitis B surface antigen (HBsAg) by a mean of 2.0 log₁₀, or a 99% reduction in HBsAg, and a 200 mg dose lowered HBsAg by a mean of 1.4 log₁₀, or 96% reduction...