We will continue to invest in expanding and improving our intellectual property protection for our GalXCTM RNAi platform and all its associated technologies. In that effort, we seek worldwide patent coverage for novel molecules, pharmaceutical formulations and methods of use. Our focus on such innovation provides patent coverage for the treatment of disease targets, methods of manufacture and other novel uses for the molecules originating from our research and development efforts. We believe we have a robust and growing patent portfolio covering our proprietary GalXC RNAi platform and other RNAi gene targeting technologies. As of April 15, 2019, our global patent estate, not including the patents and patent applications we have licensed, includes over 50 issued patents or allowed patent applications and over 100 pending patent applications in over 40 different patent families protecting the commercial development of our RNAi molecules and associated delivery technologies.
Our activities in the intellectual property area focus on two areas:
The City of Hope (COH), a leading academic and research hospital, has granted us the exclusive worldwide license for RNA structures having a 25 to 30 nucleotide sense strand, a blunt end at the 3’ end of the sense strand and a one to four nucleotide overhang at the 3’ end of the antisense strand. This structural approach is referred to as Dicer substrate short interfering RNA, or DsiRNA, and is covered by several issued US patents, including US patents no. 8,084,599 and 8,796,444, titled, “Methods and Compositions for the Specific Inhibition of Gene Expression by Double-Stranded RNA.” It serves as the structural base of our GalXC™ RNAi platform. From that base we have continued to innovate in the design, durability and potency of our DsiRNA constructs.
GalXC RNAi Platform
We have also pioneered an RNAi molecule technology that adds multiple functional features to the RNAi triggers, which is in part facilitated by their extra length, and we refer to these as extended Dicer substrate short interfering RNAs, or DsiRNA-EX. This technology is particularly suited to the development of our GalXC compounds, which comprise DsiRNAs that possess a chemically attached targeting component, making them highly efficient in accessing targeted tissue and suitable for subcutaneous injection. GalXC compounds are molecules wherein the delivery/targeting vehicle is directly attached, or conjugated, to the RNAi molecule. The extra length of the DsiRNA-EX molecules in GalXC compounds provides multiple avenues to favorably perform such conjugation and improve the activity of the guide strand in mRNA knockdown. We are using our proprietary GalXC platform to advance the development of next-generation RNAi-based therapies designed to silence disease-driving genes in the liver. This technology is broadly covered by several patents and patent applications, including US patents no. 8,349,809, 8,513,207, and 8,927,705.