NEW YORK (GenomeWeb) – Benitec Biopharma this week announced that it is appealing the European Patent Office's recent revocation of a patent covering the company's core expressed RNAi technology, which had been successfully challenged by biotech firm Galapagos and agro-chemical giant BASF.
Meanwhile, the company disclosed that a hearing on another of its European patents facing opposition has been scheduled for early 2015.
The revoked patent — EP1555317 — is owned by Australia's Commonwealth Scientific and Industrial Research Organization and was exclusively licensed to Benitec for human health applications. In a statement, Benitec said that it plans to "address the features of the main claims [in the patent] that were found unpatentable."
Specifically, the EPO took issue with the description of the length limitation of RNA constructs generated by the patented technology. According to the EPO, the patent referred to a nucleotide sequence "of greater than 20 nucleotides which is substantially identical to the nucleotide sequence of [a] target gene," but this did not jibe with language elsewhere in the patent.
Benitec noted that this length limitation was contested during the initial prosecution of the patent, but that CSIRO was able to provide arguments addressing the patent office's concerns. The company said the appeal will enable it and CSIRO to once again argue for the patent's validity.
The EP1555317 patent is entitled "Synthetic Genes and Genetic Constructs Comprising the Same," and stems from the work of company co-founder and CSIRO researcher Michael Graham. It claimed the use of recombinant DNA to "post-transcriptionally modify or modulate the expression of a target gene" via RNAi.
Granted in 2011, the patent was opposed by BASF and Galapagos, which had filed its opposition under the name "Strawman Limited." When it announced the patent's revocation earlier this year, Benitec noted that it's novelty and inventiveness were not at issue, and that the EPO's decision was inconsistent with the findings of the US and British patent offices, both of which previously maintained patents from the Graham intellectual property family.
The patent battle in the US, in fact, marked the most tumultuous period in Benitec's history.
Under previous management, it sued three companies in 2004 for infringing its key US Graham patent — No. 6,573,099. One of those companies — the now-defunct RNAi drug developer Nucleonics — challenged the patent at the US Patent and Trademark Office and succeeded in having it invalidated.
With its IP in question and under the pressure of legal costs, Benitec nearly folded. However, in 2010, the company ultimately prevailed in having the patent fully upheld, opening the door to a number of successful financing rounds that allowed it to regain the rights to its lead drug candidate, the Phase I/IIa hepatitis C treatment TT-034, and ramp up other drug-development programs.
Benitec's management previously told Gene Silencing News that the company's success defending the '099 patent boded well for its chances in front of the EPO. The ruling on the '317 patent, however, suggests that that is not necessarily the case and that the firm may face setbacks with two other of its European patents under review.
One of those — EP1068311 — is entitled "Method and Means for Obtaining Modified Phenotypes" and relates to the use of double-stranded RNA to reduce the expression of a nucleic acid sequence of interest in eukaryotic cells, particularly as a means to establish viral resistance. It is owned by CSIRO and licensed to Benitec, and is being opposed by BASF, ag-bio firm Syngenta, Galapagos, the Carnegie Institution, and the University of Massachusetts.
Benitec said this week that the first hearing in front of the EPO's opposition division over the '311 patent is scheduled for Jan. 7 and 8, 2015.
In a statement, Sakura Holloway, Benitec's recently appointed in-house IP counsel, said that the company and CSIRO have "a high degree of confidence that the outcome of [this] hearing will be favorable.
"There are a number of features that differ between the ['311] patent and the ['317] patent, in particular the length restriction that was the reason for the EPO decision to revoke the patent does not exist" in the '311 patent, he added.
Meanwhile, a third patent held by CSIRO and licensed to Benitec — EP1624060 — has been opposed by BASF and Galapagos. Entitled "Control of Gene Expression," it claims recombinant DNA for the post-transcriptional modification or modulation of target gene expression via RNAi.
A date for an oral hearing on this patent has not been set.