Alnylam receives small interfering RNA therapeutics patent
making small interfering RNAs with and without chemical
modifications, which is set to have far reaching implications in
future drug discovery.
Sequencing of the human genome coupled with the ability of siRNA to specifically silence genes based on sequence creates a real opportunity for development of powerful new RNAi-based therapeutics.
Further support comes from recent advances in nucleic acid chemistry and pioneering delivery technologies initially developed for gene therapy.
Interest in RNAi is thus growing rapidly across many disciplines, from plant and developmental biology to drug development, evidenced by an increasing number of publications in the scientific literature.
The newly issued US patent (No. 7,078,196) covers methods of making small interfering RNAs (siRNAs), and includes claims covering chemical modifications needed to introduce "drug-like" properties in RNAi therapeutics.
The claims, 79 in total for the patent, specifically covers the preparation of double-stranded RNAs having structural elements that are recognised as critical requirements for the therapeutic activity of siRNAs.
The claims also cover broad forms of such chemical modifications, including those of the 2' hydroxy position of the ribose backbone used to generate so-called "no-ribose" or "siNA" forms of RNAi therapeutics.
These chemical modifications include the use of phosphorothioate backbone linkages or 2'-0-methyl, and/or 2'-fluoro chemistries, irrespective of the percent of nucleotides modified and the extent of such modifications.
"We are gratified that the USPTO has acknowledged the key inventions of Professor Thomas Tuschl performed at the Max Planck Institute in Gottingen," said Peter Gruss, President of the Max Planck Society.
"This critical patent for RNAi therapeutics is owned by the Max Planck Society and has been licensed exclusively to Alnylam for commercialisation. We are impressed with the progress Alnylam is making in its effort to develop innovative medicines using one of our Institute's most important scientific discoveries."
Since many diseases are caused by the inappropriate activity of specific genes, the ability to silence genes selectively through RNAi could provide a new way to treat a wide range of human diseases.
One method to activate RNAi is with chemically synthesised small interfering RNAs, or siRNAs, which are double-stranded RNAs that are targeted to a specific disease-associated gene.
The siRNA molecules are used by the natural RNAi machinery in cells to cause highly targeted gene silencing.
"This new patent extends what we believe is an unparalleled IP estate for RNAi therapeutics that includes over 150 patents issued in the world's largest pharmaceutical markets," said John Maraganore, President and Chief Executive Officer of Alnylam Pharmaceuticals.
