Nucleonics fires new salvo at Benitec

Pennsylvania-based anti-viral therapeutics developer Nucleonics is continuing its trench warfare with Brisbane RNAi therapeutics company Benitec (ASX:BLT) and CSIRO over the legitimacy of their key patents on RNA-mediated gene-silencing technology.

In September, Nucleonics, which is developing novel expressed interfering RNA (eiRNA) therapeutics for patients with chronic hepatitis C or HIV infections, asked the Australian Commissioner for Patents to re-examine Australian Patent No 743316, jointly held by CSIRO and Benitec, titled 'Control of Gene Expression'.

Nucleonics said it would submitting new documents supporting its opposition to the patent. CEO Robert Towarnicki said the new documents provided evidence of prior art that would invalidate the CSIRO-Benitec patent, on the grounds that it lacked novelty and did not involve an innovative step at the time the patent was filed.

Towarnicki also said Nucleonics considerd the patent claim was ambiguous, and failed to provide adequate description or sufficient working example sto support the scope of the claimed subject matter.

Nucleonics remains the lone holdout in Benitec's own lawsuit, launched against three US biotechnology companies last March, in the US District Court of Delaware, alleging infringement of another Benitec patent granted by the US Patent Office. Two other companies -- Ambion and Genscript -- have since agreed to pay royalties.

Towarnicki said the supplementary documents supporting the re-examination of the Australian patent were "a further demonstration of our commitment to use all available legal avenues to expose the inherent weaknesses in Benitec's patent portfolio".

"We will not permit Benitec to use its invalid patent claims to interfere with and attempt to prevent those working to advance eiRNA technology from developing needed therapeutics for chronic viral and other disease indications around the world," he said.

Benitec did not respond to a request for comment on this issue.

On Thursday, the company called a trading halt while it finalised a capital raising, details of which are expected to be announced on Monday.