The US patent - entitled Genetic Constructs for Delaying or Repressing the Expression of a Target Gene - relates to the use of synthetic genes to modify gene expression in a cell, tissue or organ of a transgenic organism. The invention covers novel synthetic genes and genetic constructs capable of repressing, delaying or otherwise reducing the expression of an endogenous gene or a target gene in an organism when introduced thereto.
Benitec's DNA directed RNAi (ddRNAi) technology uses RNA interference (RNAi) - a natural cellular process - to specifically silence problem genes.
A double-stranded RNA, with the sequence of one strand matching the targeted mRNA, is delivered to the cell and sets off a cellular process that destroys the mRNA, effectively silencing the gene by preventing the expression of its protein.
Benitec currently has 7 issued patents in 5 jurisdictions, including the USA, UK and Australia, and has over 60 pending RNAi based patent applications in advanced stages of prosecution in 14 other jurisdictions.
John McKinley, Chairman and Chief Executive Officer of Benitec Limited, said:"We believe Benitec's patent estate is clear and represents an enforceable position in DNA-directed gene silencing."
"Benitec will consider additional infringement actions as we deem appropriate in other jurisdictions."
The company claims that its ddRNAi approach has several potential advantages when compared with alternative gene silencing technologies under development, such as antisense RNA, and synthetic and chemically modified siRNA. These advantages include more versatile delivery options, simultaneous multiple gene disabling, the ability to silence genes in whole organisms (transgenic ddRNAi), and the ability to control the expression and timing of gene silencing.
Today, some of the world's most serious diseases are demonstrating resistance to existing drugs, as is the case with the increasing problem of antibiotic-resistant bacteria. Benitec's multi-hit ddRNAi technology potentially provides a single agent that could deliver potent and specific 'drugs' effectively against multiple targets. Most cancers and HIV, in particular, have high mutation rates that increase the probability of resistant variants.
Benitec made history when became the first company to trigger RNAi in human and mammalian cells and in whole mammals and holds the only issued patents covering RNAi in mammalian cells.