Gene silencing patent argument grows louder

Queensland biotechnology company Benitec (ASX: BLT) says CSIRO has "no claim" to its patented technology for gene silencing by RNA interference (RNAi).

In a statement to the Australian Stock Exchange issued in response to a CSIRO press release last week, and to an article in Australian Biotechnology News this week, Benitec CEO John McKinley said, "We've been aware of this claim of CSIRO for over two years and more recently of their opposition to the [agrochemical company] Syngenta patent in Australia."

The CSIRO press release announced that its Plant Industry division was releasing its high-throughput RNAi gene-silencing vectors for free use in not-for profit research. But the release also claimed RNAi was "conceived and developed at CSIRO Plant Industry in 1994" and used double-stranded RNA as a trigger to degrade messenger RNA -- the RN-encoded instructions for protein synthesis in cells.

It also said Plant Industry researchers were the first to demonstrate gene silencing by RNAi in a living organism. CSIRO's claim for priority rests on an experiment by Dr Peter Waterhouse that demonstrated the phenomenon induced resistance to a virus in tobacco plants.

Benitec's claim rests on Dr Mick Graham's demonstration of gene silencing by RNAi in mammalian and plant cells while working for the Queensland Department of Primary Industries. Graham formerly worked with Waterhouse's CSIRO group, but left in 1995.

Plant Industry's intellectual property manager, Dr Rob Defeyter, said yesterday, in response to Benitec's most recent statement, "CSIRO stands by its claims. We are very confident of our position, based on evidence submitted to the Australian Patent Office."

Defeyter said CSIRO had filed 2000 pages of documents in opposition to rival patent applications lodged in 1998 by Benitec and the international agrochemical company Syngenta.

CSIRO also said it had recently filed considerable evidence with the patent office in support of its position that it is the rightful owner of the Benitec/QDPI patent application.

Australian Biotechnology News understands that CSIRO's claim for priority rests, in part, on its belief that Graham's demonstration of RNAi gene-silencing in mammalian cells relied upon techniques developed while he was working with CSIRO Plant Industry.

In yesterday's statement to the ASX, Benitec's McKinley said, "This matter remains in the hands of our lawyers, Freehills, to ensure that we preserve all of our rights to this important technology.

"We remain of the view that we have the priority date for this technology which is protected by our three issued patents, including one in Australia, and our pending patent applications in Australia and 18 other jurisdictions.

"Our technology is regarded internationally as fundamental to the successful commercialisation of this revolution in genetics and our view is that CSIRO has no claim to our technology.

"QDPI/Benitec are continuing to develop and license their technology in Australia and internationally. Our commercial partners recognise the strength of our IP position and we will build upon our successful commercialisation strategy as our filed patents continue to be issued on a worldwide basis."

Benitec's research and technology director, Dr Ken Reed, told Australian Biotechnology News yesterday his company had gone to "extraordinary lengths" to reach a "mutual understanding" with CSIRO, including two meetings with CSIRO chief executive Dr Geoff Garrett.