Regulus Therapeutics Inc., a biopharmaceutical company leading the discovery and development of innovative medicines targeting microRNAs, has announced that the Japan Patent Office has issued a decision to grant a patent in the ‘Sarnow’ patent series for microRNA-122 (miR-122) therapy in the treatment of chronic hepatitis C virus (HCV) infection.

The Sarnow patent estate, owned by Stanford University and exclusively licensed to Regulus, has already produced patents in Australia, Europe and the United States, and covers the use of a broad class of anti-miR inhibitors of miR-122 for the treatment of HCV.

Regulus also announced that the US Patent and Trademark Office has allowed claims in a third Sarnow patent application, relating to the use of anti-miR-122 agents as monotherapy or in combination with other anti-viral therapies, to treat HCV-infected patients.

“The recent allowance of miR-122 therapy claims further broadens Regulus’ dominant and comprehensive intellectual property estate covering microRNA therapeutics,” said Kleanthis G. Xanthopoulos, Ph.D., president and CEO of Regulus Therapeutics Inc. “The HCV landscape continues to be a dynamic and ever-evolving space, with improvements upon direct-acting antiviral therapy on the horizon. We believe anti-miR-122 is attractively positioned for use in combination with direct-acting antivirals to further reduce viral load and suppress viral resistance.”

The discovery of microRNA in humans during the last decade is one of the most exciting scientific breakthroughs in recent history. microRNAs are small RNA molecules, typically 20 to 25 nucleotides in length, that do not encode proteins but instead regulate gene expression. More than 700 microRNAs have been identified in the human genome, and over one-third of all human genes are believed to be regulated by microRNAs. A single microRNA can regulate entire networks of genes. As such, these molecules are considered master regulators of the human genome. microRNAs have been shown to play an integral role in numerous biological processes, including the immune response, cell-cycle control, metabolism, viral replication, stem cell differentiation and human development. Most microRNAs are conserved across multiple species, indicating the evolutionary importance of these molecules as modulators of critical biological pathways. Indeed, microRNA expression, or function, has been shown to be significantly altered in many disease states, including cancer, heart failure and viral infections. Targeting microRNAs with anti-miRs, antisense oligonucleotide inhibitors of microRNAs, or miR-mimics, double-stranded oligonucleotides to replace microRNA function opens potential for a novel class of therapeutics and offers a unique approach to treating disease by modulating entire biological pathways.