US firm Regulus Therapeutics and GlaxoSmithKline have partnered to develop and commercialise therapeutic targets for hepatitis C viral infection (HCV) using microRNA therapeutics targeting miR-122 antagonists.

The miR-122 is a liver-expressed microRNA that has been shown to be a critical endogenous host factor for HCV’s replication, and anti-miRs targeting miR-122 have been shown to block HCV infection.

Regulus will receive additional upfront and early-stage milestone payments and could get over $150m in miR-122-related combined payments as part of the deal, along with royalty payments on sales of any drugs developed under the agreement.

Regulus, a joint venture between Alnylam Pharmaceuticals and Isis Pharmaceuticals, controls the exclusive patent rights covering miR-122 antagonists and their use as HCV therapeutics in the US, Europe and Japan.

Regulus expects to identify a potential drug candidate in late 2010, and file an application with the Food and Drug Administration in 2011.