Regulus Therapeutics Inc announced the establishment of a new collaboration with GlaxoSmithKline (GSK) to develop and commercialize microRNA therapeutics targeting microRNA-122 in all fields with Hepatitis C Viral infection (HCV) as the lead indication. Under the terms of the new collaboration, Regulus will receive additional upfront and early-stage milestone payments with the potential to earn more than US$ 150 million in miR-122-related combined payments, and tiered royalties up to double digits on worldwide sales of products.

“This new collaboration with GSK demonstrates the clear scientific leadership that Regulus has established in advancing a whole new frontier of pharmaceutical research. microRNA therapeutics target the pathways of human diseases, not just single disease targets, and hold considerable promise as novel therapies across a broad range of unmet medical needs,” said Kleanthis G Xanthopoulos, president and chief executive officer of Regulus. “It also further validates Regulus’ microRNA product platform built on fundamental biology of human diseases and intellectual property, and also extends the therapeutic scope of our existing collaboration formed with GSK in 2008. Furthermore, the funding from this alliance supports Regulus’ efforts in advancing high impact, novel medicines based on microRNA biology to patients.”

The collaboration provides GSK with access to Regulus’ comprehensive and robust intellectual property estate. Regulus exclusively controls patent rights covering miR-122 antagonists and their use as HCV therapeutics in the United States, Europe, and Japan, including but not limited to the patent families which encompass: the ‘Sarnow’ patent pertaining to the method of use of anti-miR-122 to inhibit HCV replication, the ‘Esau’ patent application claiming the use of anti-miRs targeting miR-122 as inhibitory agents, the ‘Tuschl III’ patent claiming composition of matter for miR-122 and complementary oligonucleotides, and the ‘Manoharan’ patent claiming antagomirs, including antagomirs targeting miR-122.

miR-122 is a liver-expressed microRNA that has been shown to be a critical endogenous “host factor” for the replication of HCV, and anti-miRs targeting miR-122 have been shown to block HCV infection (Jopling et al. (2005) Science 309, 1577-81). In earlier work, scientists at Alnylam and Isis demonstrated the ability to antagonize miR-122 in vivo using chemically modified single-stranded anti-miR oligonucleotides. Further, work by Regulus scientists and collaborators showed that inhibiting miR-122 results in significant inhibition of HCV replication in human liver cells, suggesting that antagonism of miR-122 may comprise a novel “host factor” therapeutic strategy. Regulus scientists have shown in multiple preclinical studies a robust HCV antiviral effect following inhibition of miR-122. Regulus plans to identify a clinical development candidate in the second half of 2010 and file an investigational new drug (IND) application in 2011.

The discovery of microRNA in humans is one of the most exciting scientific breakthroughs in the last decade.

Regulus Therapeutics is a biopharmaceutical company leading the discovery and development of innovative new medicines based on microRNAs.