Seed World

CSIRO Maintains Key Patent for shRNA Gene Silencing Technology After European Opposition

The Commonwealth Scientific and Industrial Research Organisation (CSIRO) — Australia’s leading science agency — has successfully defended another key patent for RNA interference (RNAi) gene silencing technology after oppositions by multiple opponents in Europe.

RNAi technology is a powerful method that is widely used as a research tool to test the function of genes. The technology is being developed for a range of targeted therapies in humans and animals, and agricultural applications for innovative plant products. Human therapeutic applications under development using RNAi include treatment of viral diseases such as hepatitis and other diseases including cancers. Animal applications include the selection of production traits in livestock and the protection against diseases such as influenza in chickens.
The granted European patent (EP1650306), also known as the Wang patent, was maintained in an amended form as confirmed in a decision which issued recently from the European Patent Office (EPO). The patent had been opposed by two parties, BASF and Strawman Limited. The maintained claims of the patent are directed to the use of short hairpin RNA molecules which are produced from genetic constructs, also known as shRNA technology, and has particular relevance to use in mammalian cells. CSIRO also holds two similar patents in the United States, patent numbers 8,183,217 and 8,334,374.
The European decision follows the successful defence of another foundational RNAi patent in Europe (EP1068311, Waterhouse et al) by CSIRO earlier this year after opposition by four opponents. The EPO found that the patented DNA-delivered hairpin RNA technology was novel and inventive. That decision has been appealed by three of the opponents. The Waterhouse patent covers use of the technology in both plants and animals, as do the Wang patents.
The European patents are a key part of CSIRO’s extensive RNAi portfolio of 78 granted patents worldwide, stemming from the pioneering work of CSIRO scientists led by Dr Peter Waterhouse who first developed and tested hairpin RNA in 1997. The patent portfolio has been licensed to more than 35 licensees including Bayer CropScience who have exclusive rights to certain plant species. CSIRO has also made available a series of vectors for hairpin RNA in plants and distributed these free of charge to more than 4000 academic and not-for-profit research organisations and universities.
Since its first use at CSIRO, hairpin RNA technology has revolutionised the search for genes responsible for valuable traits in many crop species. The technology has also been developed for use in animals, particularly in mammals where shorter RNAi molecules (shRNA) are commonly used. The maintained patents in Europe and the corresponding patents in the US cover applications in both plants and animals.

CSIRO makes its patented RNAi technologies available for licensing for research use and for the development of commercial products in both plants and animals.