Dicerna Pharmaceuticals, Inc., a second generation RNA interference (RNAi) company, announced that the United States Patent and Trademark Office (USPTO) has issued patent claims specific to double-stranded RNAs directed against the important oncology gene target KRAS. US patent 8,372,816, titled “Methods and compositions for the specific inhibition of KRAS by asymmetric double-stranded RNA” was recently issued to Dicerna.

This issuance continues the expansion of Dicerna’s patent portfolio around RNAi-related technology, including the DsiRNA class defining claims of US patent 8,084,599, titled “Methods and compositions for the specific inhibition of gene expression by double-stranded RNA.”

“We are extremely pleased the USPTO has granted these most recent patent claims specific to the KRAS gene, further adding to our strong patent estate and allowing for broad therapeutic use claims in the RNAi field,” said Douglas Fambrough, chief executive officer of Dicerna. “The KRAS gene has been recognized as a target of great therapeutic potential for decades, and yet has remained undruggable. The successful application of Dicer Substrate Technology against KRAS is a key advancement that could lead to important new therapeutics for cancer treatment.”

On February 26, 2013, scientists from Japan-based, Kyowa Hakko Kirin Co., Ltd. (KHK) presented a talk entitled “Development of Lipid Nanoparticle (LNP) Based Delivery System of siRNA Targeting Extrahepatic Tumor,” at Asia TIDES: Oligonucleotide and Peptide Research, Technology and Product Development. The presentation highlighted in vivo tumour efficacy data obtained with DsiRNA targeting the KRAS gene, one of the programs from the research and development collaboration between Dicerna and KHK. The partners had previously announced in December 2011 that KHK had elected to advance this first collaborative therapeutic oncology candidate from the research stage into formal development studies, triggering a $5 million milestone payment for Dicerna. About Dicer Substrate RNAi.

Dicer is a critical enzyme involved in the RNAi gene silencing cascade and acts as the natural initiation point for this pathway by processing double-stranded RNA so that it can be used for gene silencing. Dicer then delivers these modified small RNA molecules to the mature gene silencing complex. Dicerna’s synthetic Dicer Substrate siRNA (DsiRNA) molecules are 25 or more base pairs in length and are processed by Dicer. By utilizing this distinct early entry point into the pathway, DsiRNA molecules have greater potency and longer duration of action than other RNAi approaches. In addition, DsiRNA molecules have enhanced delivery potential because their structure creates a natural conjugation point for cellular targeting agents.

Dicerna Pharmaceuticals is a private, venture-backed RNAi-focused biopharmaceutical company developing novel therapeutic agents and related drug delivery systems in oncology and other disease areas based on its proprietary Dicer Substrate Technology platform and Dicer Substrate siRNA (DsiRNA) molecules.

Kyowa Hakko Kirin is a leading biopharmaceutical company focusing on its core business area of oncology, nephrology and immunology/ allergy.