Arrowhead sheds programs, staff

In a surprise move, Arrowhead Pharmaceuticals is discontinuing development of multiple RNAi drug candidates that use the same delivery technology. The decision comes just weeks after FDA placed a hold on a clinical trial of ARC-520, a hepatitis B treatment, following the death of several non-human primates in a preclinical toxicology study of the drug. Arrowhead is abandoning three programs—ARC-520, ARC-521, and ARC-AAT—that use the same liver-targeted, intravenously administered delivery vehicle. Arrowhead will refocus its R&D on subcutaneous and non-hepatic delivery systems. As a consequence of the changes, the biotech is laying off 30% of its workforce.