USPTO grants NOA to Arrowhead’s new DPC siRNA delivery system

The US Patent and Trademark Office (USPTO) has granted a notice of allowance (NOA) to Arrowhead Research’s new formulation of dynamic polyconjugate (DPC) siRNA delivery system.

The patent application No.13/032,029 covers claims for protecting an siRNA delivery system consisting of a liver-targeted endosomolytic polymer, which is co-administered with an RNAi polynucleotide (siRNA) conjugated to a lipophilic or carbohydrate targeting moiety such as cholesterol

As demonstrated in pre-clinical studies, a >500-fold increase in the potency was observed when liver-targeted polymer with siRNA conjugated to a cholesterol were co-injected together, when compared to the siRNA-cholesterol alone.

Arrowhead president and CEO Chris Anzalone said the patent broadly covers compositions, methods, and uses for a new formulation of DPC siRNA delivery platform, where attachment of siRNA and delivery vehicle is not required to produce high-level, efficient knockdown of target genes.

“The new IP expands the DPC platform and is used in Arrowhead’s ARC-520 candidate in development for chronic hepatitis B virus (HBV) infection,” Anzalone added.

“The underlying technology enables us to create candidates with highly potent silencing activity and attractive manufacturing qualities.

“We continue to work towards a planned phase 1 trial of ARC-520, and are pleased to announce that we had a very productive pre-IND meeting with the FDA, which allows us to maintain our timeline to file an IND in Q2 2013.”